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  • 1.
    Abudayyeh, H.A.
    et al.
    Department of Physics, Al-Quds University, Jerusalem.
    Barghouthi, I.A.
    Department of Physics, Al-Quds University, Jerusalem.
    Slapak, Rikard
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Nilsson, Hans
    Swedish Institute of Space Physics / Institutet för rymdfysik.
    Centrifugal acceleration at high altitudes above the polar cap: A Monte Carlo simulation2015Ingår i: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 120, nr 8, s. 6409-6426Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A Monte Carlo simulation was used to study the outflow of O+ and H+ ions along three flight trajectories above the polar cap up to altitudes of about 15 RE. Barghouthi (2008) developed a model on the basis of altitude and velocity-dependent wave-particle interactions and a radial geomagnetic field which includes the effects of ambipolar electric field and gravitational and mirror forces. In the present work we improve this model to include the effect of the centrifugal force, with the use of relevant boundary conditions. In addition, the magnetic field and flight trajectories, namely, the central polar cap (CPC), nightside polar cap (NPC), and cusp, were calculated using the Tsyganenko T96 model. To simulate wave-particle interactions, the perpendicular velocity diffusion coefficients for O+ ions in each region were determined such that the simulation results fit the observations. For H+ ions, a constant perpendicular velocity diffusion coefficient was assumed for all altitudes in all regions as recommended by Nilsson et al. (2013). The effect of centrifugal acceleration was simulated by considering three values for the ionospheric electric field: 0 (no centrifugal acceleration), 50, and 100 mV/m. It was found that the centrifugal acceleration increases the parallel bulk velocity and decreases the parallel and perpendicular temperatures of both ion species at altitudes above about 4 RE. Centrifugal acceleration also increases the temperature anisotropy at high altitudes. At a given altitude, centrifugal acceleration decreases the density of H+ ions while it increases the density of O+ ions. This implies that with higher centrifugal acceleration more O+ ions overcome the potential barrier. It was also found that aside from two exceptions centrifugal acceleration has the same effect on the velocities of both ions. This implies that the centrifugal acceleration is universal for all particles. The parallel bulk velocities at a given value of ionospheric electric field were highest in the cusp followed by the CPC followed by the NPC. In this study a region of no wave-particle interaction was assumed in the CPC and NPC between 3.7 and 7.5 RE. In this region the perpendicular temperature was found to decrease with altitude due to perpendicular adiabatic cooling.

  • 2.
    Agües Paszkowsky, Núria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB. Research Institutes of Sweden, Unit for Data Center Systems and Applied Data Science, Sweden.
    Brännvall, Rickard
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB. Research Institutes of Sweden, Unit for Data Center Systems and Applied Data Science, Sweden.
    Carlstedt, Johan
    Research Institutes of Sweden, Unit for Data Center Systems and Applied Data Science, Sweden.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kovács, György
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Liwicki, Marcus
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Vegetation and Drought Trends in Sweden’s Mälardalen Region – Year-on-Year Comparison by Gaussian Process Regression2020Ingår i: 2020 Swedish Workshop on Data Science (SweDS), IEEE, 2020Konferensbidrag (Refereegranskat)
    Abstract [en]

    This article describes analytical work carried out in a pilot project for the Swedish Space Data Lab (SSDL), which focused on monitoring drought in the Mälardalen region in central Sweden. Normalized Difference Vegetation Index (NDVI) and the Moisture Stress Index (MSI) – commonly used to analyse drought – are estimated from Sentinel 2 satellite data and averaged over a selection of seven grassland areas of interest. To derive a complete time-series over a season that interpolates over days with missing data, we use Gaussian Process Regression, a technique from multivariate Bayesian analysis. The analysis show significant differences at 95% confidence for five out of seven areas when comparing the peak drought period in the dry year 2018 compared to the corresponding period in 2019. A cross-validation analysis indicates that the model parameter estimates are robust for temporal covariance structure (while inconclusive for the spatial dimensions). There were no signs of over-fitting when comparing in-sample and out-of-sample RMSE.

  • 3.
    Aires, Filipe
    et al.
    LERMA, Observatoire de Paris, Paris, France; Estellus, Paris, France.
    Prigent, Catherine
    LERMA, Observatoire de Paris, Paris, France; Estellus, Paris, France.
    Buehler, Stefan A.
    Universität Hamburg, Hamburg, Germany.
    Eriksson, Patrick
    Chalmers University of Technology, Gothenburg, Sweden.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Crewell, Susanne
    Cologne University, Cologne, Germany.
    Towards more realistic hypotheses for the information content analysis of cloudy/precipitating situations – Application to a hyperspectral instrument in the microwave2019Ingår i: Quarterly Journal of the Royal Meteorological Society, ISSN 0035-9009, E-ISSN 1477-870X, Vol. 145, nr 718, s. 1-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Information Content (IC) analysis can be used before an instrument is built to estimate its retrieval uncertainties and analyse their sensitivity to several factors. It is a very useful method to define/optimise satellite instruments. IC has shown its potential to compare instrument concepts in the infrared or the microwaves. IC is based on some hypotheses such as the the gaussian character of the Radiative Transfer (RT) and instrument errors, the first guess errors (Gaussian character, std and correlation structure), or the linearisation of the RT around a first guess. These hypotheses are easier to define for simple atmospheric situations. However, even in the clear‐sky case, their complexity has never ceased to increase towards more realism, to optimise the assimilation of satellite measurements in the Numerical Weather Prediction (NWP) systems. In the cloudy/precipitating case, these hypotheses are even more difficult to define in a realistic way as many factors are still very difficult to quantify. In this study, several tools are introduced to specify more realistic IC hypotheses than the current practice. We focus on the microwave observations as this is more pertinent for clouds and precipitation. Although not perfect, the proposed solutions are a new step towards more realistic IC assumptions of cloudy/precipitating scenes. A state‐dependence of the RT errors is introduced, the first guess errors have a more complex vertical structure, the IC is performed simultaneously on all the hydrometeors to take into account the contamination effect of the RT input uncertainties, and the IC is performed on a diversified set of cloudy/precipitating scenes with well‐defined hydrometeor assumptions. The method presented in this study is illustrated using the HYperspectral Microwave Sensor (HYMS) instrument concept with channels between 6.9 and 874 GHz (millimeter and sub‐millimeter regions). HYMS is considered as a potential next generation microwave sounder.

  • 4.
    Aires, Filipe
    et al.
    Estellus, Paris, France;LERMA, Observatoire de Paris, Paris, France;Water Center, Columbia University, New York, USA.
    Prigent, Catherine
    Estellus, Paris, France;LERMA, Observatoire de Paris, Paris, France.
    Orlandi, Emiliano
    Institute for Geophysics and Meteorology, University of Cologne, Cologne, Germany.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Eriksson, Patrick
    Global Environmental Measurements and Modeling, Chalmers University of Technology, Gothenburg, Sweden.
    Crewell, Susanne
    Institute for Geophysics and Meteorology, University of Cologne, Cologne, Germany.
    Lin, Chung-Chi
    Earth Observation Projects Department, ESA, ESTEC, Noordwijk, Netherlands.
    Kangas, Ville
    Earth Observation Projects Department, ESA, ESTEC, Noordwijk, Netherlands.
    Microwave hyperspectral measurements for temperature and humidity atmospheric profiling from satellite: The clear-sky case2015Ingår i: Journal of Geophysical Research - Atmospheres, ISSN 2169-897X, E-ISSN 2169-8996, Vol. 120, nr 21, s. 11334-11351Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study investigates the benefits of a satellite HYper-spectral Microwave Sensor (HYMS) for the retrieval of atmospheric temperature and humidity profiles, in the context of Numerical Weather Prediction (NWP). In the infrared, hyper-spectral instruments have already improved the accuracy of NWP forecasts. Microwave instruments so far only provide observations for a limited number of carefully selected channels. An information content analysis is conducted here to assess the impact of hyper-spectral microwave measurements on the retrieval of temperature and water vapor profiles under clear-sky conditions. It uses radiative transfer simulations over a large variety of atmospheric situations. It accounts for realistic observation (instrument and radiative transfer) noise and for a priori information assumptions compatible with NWP practices. The estimated retrieval performance of the HYMS instrument is compared to those of the microwave instruments to be deployed on board the future generation of European operational meteorological satellites (MetOp-SG). The results confirm the positive impact of a HYMS instrument on the atmospheric profiling capabilities compared to MetOp-SG. Temperature retrieval uncertainty, compared to a priori information, is reduced by 2 to 10%, depending on the atmospheric height, and improvement rates are much higher than what will be obtained with MetOp-SG. For humidity sounding these improvements can reach 30%, a significant benefit as compared to MetOp-SG results especially below 250 hPa. The results are not very sensitive to the instrument noise, under our assumptions. The main impact provided by the hyper-spectral information originates from the higher resolution in the O2 band around 60 GHz. The results are presented over ocean at nadir but similar conclusions are obtained for other incidence angles and over land.

  • 5.
    Akner, Malcolm
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Validating results from the Molten Salt Reactor Experiment by use of turbulent CFD simulations: A study of a modified U-tube shell-and-tube primary heat exchanger and radiator with molten salts2021Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Background

    Nuclear reactors utilizing molten fuels rather than solid fuels show a massive advantage in energy yield, waste handling and safety features. The only successful reactor utilizing a molten fuel was called the ‘Molten Salt Reactor Experiment’ (MSRE), built and operated in the Oak Ridge national laboratory (ORNL) in Tennessee, U.S.A. during the 1960s. The molten salts in question are fluoride compounds under the name of “FLiBe”. In this thesis, the heat exchangers of the MSRE are modelled and simulated, with the aim to test whether current computational fluid dynamics (CFD) software and mathematical models can accurately predict molten salt heat transfer behaviour. 

    Methods

    All programs used are open-source and/or free-access to facilitate open collaboration between researchers in this growing field. All models and findings produced in this thesis are free to use for future research.

    • The program Onshape was used to draw CAD-models based on hand-drawn technical documents released by ORNL.
    • Several programs, e.g., Simscale and Salome, were used to create high detailed meshes of the heat exchangers.
    • The CFD software Simscale and OpenFOAM have been used to simulate the heat exchangers, using the 𝑘 − 𝜔 𝑆𝑆𝑇 Reynolds averaged Navier-Stokes (RANS) turbulence model to perform a multiregion conjugate heat transfer (CHT) analysis.
    • The program Paraview has been used for all post-processing on the large datasets. 

    Results

    • A working toolchain with open-source programs for CFD has been identified.
    • Highly detailed, full-scale and accurate CAD-drawings of the two heat exchangers have been produced.
    • Models have been finely meshed, containing tens of millions of cells, with good quality measures.
    • The simulations produced physically sound and valuable data: 
      • Great heat transfer predictive capability with high accuracy to the data presented by ORNL.
      • Pressure data showed a consistent over-prediction with a factor of ~2. Possibility of error within the MSRE measurement. 

    Conclusions

    • CHT using modern turbulence methods work well for the intended purpose and can be used by industry to simulate molten salt heat transfer.
    • Open-source programs perform well and can be used by researchers to share ideas and progress.
    • Doubts around certain measurements from the MSRE, showing large uncertainties.
    • Future projects have been outlined to continue the work performed in this thesis.
    • Molten salt reactors show fantastic promise as an energy generation method and should be seriously considered for the future of clean, reliable energy.
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  • 6.
    Alepuz, Javier Pérez
    et al.
    University of Alicante, POBox 99, 03080, Alicante, Spain.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. University of Toronto Institute for Aerospace Studies, 4925 Dufferin Street, Toronto, Ontario M3H 5T6, Canada.
    Pomares, Jorge
    University of Alicante, POBox 99, 03080, Alicante, Spain.
    Direct image-based visual servoing of free-floating space manipulators2016Ingår i: Aerospace Science and Technology, ISSN 1270-9638, E-ISSN 1626-3219, Vol. 55, s. 1-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents an image-based controller to perform the guidance of a free-floating robot manipulator. The manipulator has an eye-in-hand camera system, and is attached to a base satellite. The base is completely free and floating in space with no attitude control, and thus, freely reacting to the movements of the robot manipulator attached to it. The proposed image-based approach uses the system's kinematics and dynamics model, not only to achieve a desired location with respect to an observed object in space, but also to follow a desired trajectory with respect to the object. To do this, the paper presents an optimal control approach to guiding the free-floating satellite-mounted robot, using visual information and considering the optimization of the motor commands with respect to a specified metric along with chaos compensation. The proposed controller is applied to the visual control of a four-degree-of-freedom robot manipulator in different scenarios.

  • 7.
    Alho, Markku
    et al.
    School of Electrical Engineering, Aalto University, Maarinkatu 8, PO Box 15500, FI-00760 Aalto, Finland; Department of Physics, University of Helsinki, PO Box 68, FI-00014 Helsingin Yliopisto, Helsinki, Finland.
    Jarvinen, Riku
    School of Electrical Engineering, Aalto University, Maarinkatu 8, PO Box 15500, FI-00760 Aalto, Finland; Finnish Meteorological Institute, PO BOX 503, FI-00101 Helsinki, Finland.
    Wedlund, Cyril Simon
    Space Research Institute, Austrian Academy of Sciences, Schmiedlstraße 6, AT-8042 Graz, Austria.
    Nilsson, Hans
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Swedish Institute of Space Physics, PO Box 812, SE-981 28 Kiruna, Sweden.
    Kallio, Esa
    School of Electrical Engineering, Aalto University, Maarinkatu 8, PO Box 15500, FI-00760 Aalto, Finland.
    Pulkkinen, Tuija I.
    School of Electrical Engineering, Aalto University, Maarinkatu 8, PO Box 15500, FI-00760 Aalto, Finland; Department of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143, US.
    Remote sensing of cometary bow shocks: modelled asymmetric outgassing and pickup ion observations2021Ingår i: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 506, nr 4, s. 4735-4749Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite the long escort by the ESA Rosetta mission, direct observations of a fully developed bow shock around 67P/Churyumov-Gerasimenko have not been reported. Expanding on our previous work on indirect observations of a shock, we model the large-scale features in cometary pickup ions, and compare the results with the ESA Rosetta Plasma Consortium Ion Composition Analyser ion spectrometer measurements over the pre-perihelion portion of the escort phase. Using our hybrid plasma simulation, an empirical, asymmetric outgassing model for 67P, and varied interplanetary magnetic field (IMF) clock angles, we model the evolution of the large-scale plasma environment. We find that the subsolar bow shock standoff distance is enhanced by asymmetric outgassing with a factor of 2 to 3, reaching up to 18 000 km approaching perihelion. We find that distinct spectral features in simulated pickup ion distributions are present for simulations with shock-like structures, with the details of the spectral features depending on shock standoff distance, heliocentric distance, and IMF configuration. Asymmetric outgassing along with IMF clock angle is found to have a strong effect on the location of the spectral features, while the IMF clock angle causes no significant effect on the bow shock standoff distance. These dependences further complicate the interpretation of the ion observations made by Rosetta. Our data-model comparison shows that the large-scale cometary plasma environment can be probed by remote sensing the pickup ions, at least when the comet’s activity is comparable to that of 67P, and the solar wind parameters are known.

  • 8.
    Alho, Markku
    et al.
    Department of Electronics and Nanoengineering, School of Electrical Engineering, Aalto University, Aalto, Finland.
    Wedlund, Cyril Simon
    Department of Physics, University of Oslo, Oslo, Norway.
    Nilsson, Hans
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Swedish Institute of Space Physics, Kiruna, Sweden.
    Kallio, Esa
    Department of Electronics and Nanoengineering, School of Electrical Engineering, Aalto University, Aalto, Finland.
    Jarvinen, R.
    School of Electrical Engineering, Aalto University, Aalto, Finland. Finnish Meteorological Institute, Helsinki, Finland.
    Pulkkinen, T.I
    School of Electrical Engineering, Aalto University, Aalto, Finland. Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI,USA.
    Hybrid modeling of cometary plasma environments: II. Remote-sensing of a cometary bow shock2019Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 630, artikel-id A45Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Context. The ESA Rosetta probe has not seen direct evidence of a fully formed bow shock at comet 67P/Churyumov–Gerasimenko (67P). Ion spectrometer measurements of cometary pickup ions measured in the vicinity of the nucleus of 67P are available and may contain signatures of the large-scale plasma environment.

    Aims. The aim is to investigate the possibility of using pickup ion signatures to infer the existence or nonexistence of a bow shock-like structure and possibly other large-scale plasma environment features.

    Methods. A numerical plasma model in the hybrid plasma description was used to model the plasma environment of a comet. Simulated pickup ion spectra were generated for different interplanetary magnetic field conditions. The results were interpreted through test particle tracing in the hybrid simulation solutions.

    Results. Features of the observed pickup ion energy spectrum were reproduced, and the model was used to interpret the observation to be consistent with a shock-like structure. We identify (1) a spectral break related to the bow shock, (2) a mechanism for generating the spectral break, and (3) a dependency of the energy of the spectral break on the interplanetary magnetic field magnitude and bow shock standoff distance.

  • 9.
    Anantha Raman, Deepa
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Thermal environment and design considerations of the Foresail-2 satellite mission2023Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The thermal design of small satellite missions is critical for ensuring the performance and longevity of onboard instruments. This thesis focuses on the thermal design of Foresail-2, a 6U CubeSat mission to Geostationary Transfer Orbit (GTO), specifically addressing the thermal challenges associated with the magnetometer located at the end of a long boom featured on the satellite.

    The objective of this research is to estimate the orbital loads, study its effects and develop an effective thermal control strategy to maintain the frame, boom and magnetometer temperature within an optimal operational range throughout the mission duration. A steady state thermal analysis is conducted to evaluate the effects of the GTO environment on the satellite structure under different operational scenarios and design conditions. To achieve the desired thermal control, several potential regulation strategies are investigated, including passive thermal coatings, insulation materials, and active cooling methods.

    Furthermore, thermal simulations are performed to predict the temperature profiles and gradients within the boom and magnetometer assembly, enabling the identification of potential hotspots or areas prone to thermal stress using ANSYS software package. These findings contribute to the implementation of thermal design modifications and the optimization of the configuration of the boom and magnetometer to enhance thermal performance.

    The results of this thesis contribute to the development of a robust thermal design for Foresail-2 mission satellite. Moreover, the methodologies and insights gained from this research can be extended to other CubeSat missions with similar thermal requirements and constraints.

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  • 10.
    Andersen, Torben
    et al.
    Lunds universitet.
    Enmark, Anita
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Integrated Modeling of Telescopes2011Bok (Övrigt vetenskapligt)
  • 11.
    Andersen, Torben
    et al.
    Lund Observatory (Sweden) .
    Owner-Petersen, Mette
    Lund Observatory (Sweden) .
    Enmark, Anita
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Image-based wavefront sensing for astronomy using neural networks2020Ingår i: Journal of Astronomical Telescopes, Instruments, and Systems, ISSN 2329-4124, Vol. 6, nr 3, artikel-id 034002Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Motivated by the potential of non-diffraction limited, real-time computational image sharpening with neu7 ral networks in astronomical telescopes, we have studied wavefront sensing with convolutional neural networks basedon a pair of in-focus and out-of-focus point spread functions. By simulation, we generated a large dataset for trainingand validation of neural networks, and trained several networks to estimate Zernike polynomial approximations forthe incoming wavefront. We included the effect of noise, guide star magnitude, blurring by wide band imagining, andbit depth. We conclude that the “ResNet” works well for our purpose, with a wavefront RMS error of 130 nm forr0 = 0.3 m, guide star magnitudes 4–8, and inference time of 8 ms. It can also be applied for closed-loop operation inan adaptive optics system. We also studied the possible use of a Kalman filter or a recurrent neural network and foundthat they were not beneficial to performance of our wavefront sensor

  • 12.
    Andersen, Torben
    et al.
    Lund Observatory, Lund University.
    Owner-Petersen, Mette
    Lund Observatory, Lund University.
    Enmark, Anita
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Neural networks for image-based wavefront sensing for astronomy2019Ingår i: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 44, nr 18, s. 4618-4621Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We study the possibility of using convolutional neural networks for wavefront sensing from a guide star image in astronomical telescopes. We generated a large number of artificial atmospheric wavefront screens and determined associated best-fit Zernike polynomials. We also generated in-focus and out-of-focus point-spread functions. We trained the well-known “Inception” network using the artificial data sets and found that although the accuracy does not permit diffraction-limited correction, the potential improvement in the residual phase error is promising for a telescope in the 2–4 m class.

  • 13.
    Andersson, Erik
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Numerical Approach to the Design and Optimisation of a Bi-Propellant Pintle Injector2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Rocket propulsion is of vital importance for space travel. New innovations are continuously developed in order to facilitate the demand of the rapidly evolving space sector. Recently a focus on reusable rockets has appeared due to the economical and environmental benefits they bring. When designing reusable launch vehicles the propellant injector becomes very important since it is a critical component when throttleabilty is desired. Which is a key element of landable rockets. Selecting an appropriate injector type therefore becomes crucial, a common injector type used for throttleable rockets is the pintle injector.

    Unfortunately the design process of the pintle injector is complicated due to the large amount of variables that must be determined. This thesis aims to solve this problem by developing a numerical method to design and optimise a pintle injector and then produce a preliminary design.

    The numerical method developed in this thesis is used to produce a preliminary design of a pintle injector designed to utilise a combination of liquid oxygen and gaseous methane, theoretically capable of a max thrust of 1000N and a throttleabilty of 5 to 1. The design had a focus on optimising the performance of the parameters sauter mean diameter, vaporisation distance and spray angle for the injector. The resulting injector showcases great performance and is deemed to show a successful preliminary design. Which shows that the numerical design and optimisation process that was developed also was successful.

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  • 14.
    Andersson, Erik
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Preliminary design of a small-scale liquid-propellant rocket engine testing platform2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Propulsion system testing before mission operation is a fundamental requirement in any project. For both industrial and commercial entities within the space industry, complete system integration into a static test platform for functional and performance testing is an integral step in the system development process. Such a platform - if designed to be relatively safe, uncomplicated and reliable - can be an important tool within academia as well, giving researchers and students a possibility for practical learning and propulsion technology research.

    In this thesis, a preliminary design for a liquid-propellant rocket engine testing platform to be used primarily for academical purposes is developed. Included in the presented design is a bi-propellant Chemical Propulsion system, gas pressure fed with Gaseous Nitrogen and using Gaseous Oxygen as oxidiser and a 70 % concentrated ethanol-water mixture as fuel. The propellant assembly contains all necessary components for operating the system and performing combustion tests with it, including various types of valves, tanks and sensors. An estimation of the total preliminary cost of selected components is presented as well. Also part of the developed platform design is a small thrust chamber made of copper, water-cooled and theoretically capable of delivering 1000 N of thrust using the selected propellants.

    A list of operations to be performed before, during and after a complete combustion test is presented at the end of the document, together with a preliminary design of a Digital Control and Instrumentation System software. Due to time limitations, the software could not be implemented in a development program nor tested with simulated parameters as part of this thesis project.

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  • 15.
    Angeria, Benyam
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Additive Manufacturing of Self-Sensing Materials2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A self-sensing material can not only carry a load but can also provide data aboutthe load and stress it’s being subjected to. Traditional additive manufacturing haslimited capabilities in producing self-sensing material. Existing 3D printers eitherused in industry or in scientific applications are either limited by closed-off software and planar motion which limits the design freedom, or the type of material orcost often limiting the attainability. Being capable of placing self-sensing materialwith full design freedom means that the sensor structure as well as the load carryingpart of the material can be tailored to the application specific use of the material,making application specific load carrying and sensing capabilities possible. Themanufacturing method produced in this aims to solve these existing limitations. Aliterature review in the topic of additive manufacturing of self-sensing material andcontinuous Carbon Fiber Reinforced Thermoplastics (CFRTPs) has been producedas a literature base. The review seeks to educate and inspire the design of an noveladditive manufacturing method and device capable of printing a self-sensing material as well as non-planar motion. A design for extruding self-sensing material andnon-planar motion has been realized through modified Commercial-Off-The-Shelf(COTS) parts and Geometric Code (G-Code). Existing hardware capable of producing this can be priced in the range of 70 000 C, but this result has been achievedwith around 200 C [42]. A software structure capable of manufacturing the selfsensing material has been produced. Real-world testing in terms of extrusion of theself-sensing material and non-planar motion has been tested and proven which arethe main practical outcomes demonstrating the technological feasibility.

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  • 16.
    Anih, Samuel
    et al.
    University of Cape Town, South Africa.
    Pagan, Adam S.
    IRS, University of Stuttgart, Germany.
    Koch, Helmut
    IRS, University of Stuttgart, Germany.
    Martinez, Peter
    South Africa.
    Laufer, René
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Herdrich, Georg
    Institute of Space Systems, Germany.
    Investigations of long-duration crewed space missions solid waste management using Waste for Energy and Volume Recovery (WEVR) experiments2020Ingår i: IAC CyberSpace Edition, International Astronautical Federation (IAF) , 2020, artikel-id 60460Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Astronauts embarking on long-duration crewed space missions to destinations further away from the Earth in the future will have to contend with challenges of proper waste management due to several constraints, such as limited resources, absence of constant resupply of consumables, limited habitable volume inside the spacecraft, isolation from the Earth system and limited waste stowage space for a longer period of the mission. The use of the high enthalpy inductively heated plasma generators IPG3 and IPG4 for decomposition of crewed space missions waste simulants was investigated during the Waste for Energy and Volume Recovery (WEVR) campaign conducted at the at the Institute of Space Systems (IRS) of the University of Stuttgart, a partner institution of the University of Cape Town’s SpaceLab. Reference waste package simulants were subjected to series of decomposition processes using the two IRS inductively heated plasma generators in Plasma Wind Tunnel 3 (PWK3). The investigations were designed to assess and characterize the responses of the various samples to thermal decomposition in the given plasma flow using oxygen and nitrogen operational gases under a thermal steady state condition leading to attendant products which were analyzed. This paper details simulant decomposition scheme during WEVR campaign in addition to results from physical and spectroscopic analysis with possible application to long duration crewed spaceflight.

  • 17.
    Anthony, Niklas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laser Interaction with Minerals Common on Asteroids2021Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Asteroids are worth studying for three reasons: planetary protection, industrial applications, and scientific knowledge. It is critical we develop technologies capable of diverting objects on collision courses with our planet. We can use the same technology to move or process asteroids and comets for materials to build structures or refuel in Low-Earth Orbit. Asteroids are also windows into the past; they were formed in the early Solar System, and could potentially have been the source of water and/or life on Earth. There are unique challenges to manipulating an asteroid or asteroid materials, which means that much of what we know about material processing needs to be revamped to fit the situation. One of the motivating drives of this research was that a laser would be an excellent tool to perform many tasks at an asteroid.

    One process of interest is laser drilling. The surface composition of asteroids is altered by aeons of space weathering; by studying the subsurface composition we can ascertain just how much it is altered and possibly by which processes. It is possible that hydrated minerals or ices exist below the surface as well, which are of great economic interest in asteroid mining. One of the greatest challenges to get under the surface of an asteroid is the low gravity: any forces or torques generated by a sampling mechanism may tip the spacecraft or launch it into deep space. A laser does not generate any significant forces, and can even be used without having to land; lasers do use a lot of electric power so the laser parameters need to be optimized to minimize the size and power requirements of the spacecraft. We found that nearly 1-cm deep holes can be made with as little as 18~J of energy using a 300-W laser.

    Laser ablation has been studied as a mechanism to redirect asteroids, but it is not particularly energy efficient at material removal. If the idea is to create a momentum exchange by removing surface material beyond an object's gravitational pull, then there could perhaps be more energy efficient mechanisms. One mechanism we investigated was spallation, where the shock wave of a laser pulse breaks off a relatively large chunk of material without having to melt and vaporize it. We found that spallation may be many times more energy efficient than ablation.

    Laser welding of metals has been of industrial interest for decades, though the welding of two different materials is still a challenge. We sought to develop a laser-based wire-attachment mechanism that can be used to anchor spacecraft to the surface of a small body or to maneuver boulders or small asteroids. When attempting to follow a traditional welding process, it was found that the two melt pools would not mix, and if it did, it was very weak. Instead, we used the laser to drill a hole and melt a wire while inserting it into the hole. This produced a solid anchor with a hold strength of up to 120~N.

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  • 18.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, M. Reza
    University of Toronto, Canada.
    Cubesat Minimoon Rendezvous Mission Synthesis and Analysis2018Ingår i: IAC-18, International Astronautical Federation, 2018, artikel-id IAC-18,A3,IP,65,x44584Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper introduces a mission concept for the remote characterization of a temporarily-captured asteroid, or “minimoon”, based on the utilization of the CubeSat form-factor. Minimoons are a subpopulation of the estimated two million Near-Earth Objects (NEOs) under 2 meters in diameter, which pass within the Moon’s orbit every year. These temporarily-captured objects do not remain in the Earth-Moon system for long, typically less than one year, and are thus a challenge for developing conventional spacecraft missions. A potential solution to this problem is to utilize the typical rapid-development timelines that CubeSat missions possess. This paper will analyze the requirements and limitations in developing a mission for a CubeSat to rendezvous or fly by a minimoon. This includes exploring the capabilities and applicability of the CubeSat technologies for such a mission, analyzing the erratic nature of minimoon orbits, lying out how such a mission project would be managed, and finally presenting a case study of such missions on the only known minimoon so far, Asteroid 2006 RH120.

  • 19.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Institute for Aerospace Studies, University of Toronto.
    Asteroid engineering: The state-of-the-art of Near-Earth Asteroids science and technology2018Ingår i: Progress in Aerospace Sciences, ISSN 0376-0421, E-ISSN 1873-1724, Vol. 100, s. 1-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents a comprehensive review of the science and technology of accessing near-Earth asteroids (NEAs), or making them accessible, for obtaining both information and resources. The survey is divided into four major groups of NEA study, namely a) discovery (population estimation and detection), b) Exploration (identification and characterization), c) deflection and redirection, and d) mining (prospecting, excavation, processing, refining, storage.). Recent research and development advancements from both industry and academia are discussed in each group, and certain specific future directions are highlighted. Some concluding remarks are made at the end, including the need for creating new educational programs to train competent engineers and researchers for the taskforce in the new field of asteroid engineering in near future

  • 20.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laboratory experiments with a laser-based attachment mechanism for small bodiesIngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Artikel i tidskrift (Refereegranskat)
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  • 21.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Laboratory experiments with a laser-based attachment mechanism for spacecraft at small bodies2021Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 189, s. 391-397Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present the results of two sets of experiments that investigate laser-based metal-to-rock attachment techniques. Asteroids and comets have low surface gravity which pose a challenge to landers with moving parts. Such parts can generate torques and forces which may tip the lander over or launch it into deep space. Thus, if a lander on a small body is to have moving parts, the spacecraft must be equipped with an anchoring mechanism. To this end, we sought to use a laser to melt and bind a piece of metal mimicking a part of a spacecraft to a rock mimicking the surface of a typical asteroid. In the first set of experiments, extra material was not fed in during the processing. The second set were performed using a standard wire feeder used in laser welding, which added metal to the experiment during processing. During the first experiments, we discovered that a traditional weld, where two melt pools mix and solidify to form a strong bond, was not possible—the melt pools would not mix, and when they did, the resulting weld was extremely brittle. The second set of experiments resulted in a physico-mechanical bond, where a hole was drilled with a laser, and a wire was melted and fed into the hole. These latter experiments were successful in forming bonds as strong as 115 N. Such an attachment mechanism can also be used to maneuver small boulders on asteroid surfaces, to redirect small, monolithic asteroids, or in space-debris removal.

  • 22.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Wanhainen, Christina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Laser-induced spallation of minerals common on asteroids2021Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 182, s. 325-331Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ability to deflect dangerous small bodies in the Solar System or redirect profitable ones is a necessary and worthwhile challenge. One well-studied method to accomplish this is laser ablation, where solid surface material sublimates, and the escaping gas creates a momentum exchange. Alternatively, laser-induced spallation and sputtering could be a more efficient means of deflection, yet little research has studied these processes in detail. We used a 15-kW Ytterbium fiber laser on samples of olivine, pyroxene, and serpentine (minerals commonly found on asteroids) to induce spallation. We observed the process with a high-speed camera and illumination laser, and used X-ray micro-tomography to measure the size of the holes produced by the laser to determine material removal efficiency. We found that pyroxene will spallate at power densities between 1.5 and 6.0 kW cm−2, serpentine will also spallate at 13.7 kW cm−2, but olivine does not spallate at 1.5 kW cm−2 and higher power densities melt the sample. Laser-induced spallation of pyroxene and serpentine can be two- to three-times more energy efficient (volume removed per unit of absorbed energy) than laser-induced spattering, and over 40x more efficient than laser ablation.

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  • 23.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Wanhainen, Christina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Penttilä, Antti
    Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Laser processing of minerals common on asteroids2021Ingår i: Optics and Laser Technology, ISSN 0030-3992, E-ISSN 1879-2545, Vol. 135, artikel-id 106724Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Asteroid mining and redirection are two trends that both can utilize lasers, one to drill and cut, the other to ablate and move. Yet little is known about what happens when a laser is used to process the types of materials we typically expect to find on most asteroids. To shed light on laser processing of asteroid material, we used a 300-W, pulsed Ytterbium fiber laser on samples of olivine, pyroxene, and serpentine, and studied the process with a high-speed camera and illumination laser at 10 000 frames per second. We also measure the sizes of the resulting holes using X-ray micro-tomography to find the pulse parameters which remove the largest amount of material using the least amount of energy. We find that at these power densities, all three minerals will melt and chaotically throw off spatter. Short, low-power pulses can efficiently produce thin, deep holes, and long, high-power pulses are more energy efficient at removing the most amount of material.

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  • 24.
    Antoja Lleonart, Guillem
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    New Generation 4-Channel GNSS Receiver: Design, Production, and Testing2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Due to the current research needs and the lack of commercial multi-channel, multi-constellation GNSS receivers, a two-board solution has been developed so it can be mated with and take advantage of the processing power of the FPGA board branded as MicroZed.

    In order to achieve the proposed goals, an initial phase for assessing and updating the older design, building, and testing of SiGe modules (including both the electronics and casings) has been carried out. The results included demonstrate performances at logging GPS-L1 data with similar C/N0 and AGC values as the previous versions of the modules and offering navigation solutions with accuracies of a few meters. Secondly, a first iteration and design proposal for the new generation receiver has been proposed for GPS and GLONASS L1 and L2, which has been manufactured and tested. Partial tests have been performed due to the flaws of the current revision of the MicroZed Board in regards to its communication peripherals, and the results have validated the receiver’s design provided certain modifications are considered for future iterations. Furthermore, voltage and frequency tests have provided results with an error of less than 7%, and signal tests have provided C/N0 values similar to those of the SiGe modules of around 47[dB-Hz] which will be a useful baseline for future iterations. Finally, a design proposal for an Interface Board used between the older NT1065_PMOD Board and other FPGA boards carrying the standardized FMC connectors has been added to the report and negotiations with manufacturers have been engaged.

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  • 25.
    Antoja, T.
    et al.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, PO Box 64, 00014 Helsinki, Finland.
    Zwitter, T.
    Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana, Slovenia.
    Gaia Early Data Release 3: The Galactic anticentre2021Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 649, artikel-id A8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aims. We aim to demonstrate the scientific potential of the Gaia Early Data Release 3 (EDR3) for the study of different aspects of the Milky Way structure and evolution and we provide, at the same time, a description of several practical aspects of the data and examples of their usage.

    Methods. We used astrometric positions, proper motions, parallaxes, and photometry from EDR3 to select different populations and components and to calculate the distances and velocities in the direction of the anticentre. In this direction, the Gaia astrometric data alone enable the calculation of the vertical and azimuthal velocities; also, the extinction is relatively low compared to other directions in the Galactic plane. We then explore the disturbances of the current disc, the spatial and kinematical distributions of early accreted versus in situ stars, the structures in the outer parts of the disc, and the orbits of open clusters Berkeley 29 and Saurer 1.

    Results. With the improved astrometry and photometry of EDR3, we find that: (i) the dynamics of the Galactic disc are very complex with oscillations in the median rotation and vertical velocities as a function of radius, vertical asymmetries, and new correlations, including a bimodality with disc stars with large angular momentum moving vertically upwards from below the plane, and disc stars with slightly lower angular momentum moving preferentially downwards; (ii) we resolve the kinematic substructure (diagonal ridges) in the outer parts of the disc for the first time; (iii) the red sequence that has been associated with the proto-Galactic disc that was present at the time of the merger with Gaia-Enceladus-Sausage is currently radially concentrated up to around 14 kpc, while the blue sequence that has been associated with debris of the satellite extends beyond that; (iv) there are density structures in the outer disc, both above and below the plane, most probably related to Monoceros, the Anticentre Stream, and TriAnd, for which the Gaia data allow an exhaustive selection of candidate member stars and dynamical study; and (v) the open clusters Berkeley 29 and Saurer 1, despite being located at large distances from the Galactic centre, are on nearly circular disc-like orbits.

    Conclusions. Even with our simple preliminary exploration of the Gaia EDR3, we demonstrate how, once again, these data from the European Space Agency are crucial for our understanding of the different pieces of our Galaxy and their connection to its global structure and history.

  • 26.
    Arenou, F.
    et al.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    Babusiaux, C.
    Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France; GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    Barstow, M. A.
    School of Physics and Astronomy/Space Park Leicester, University of Leicester, University Road, Leicester LE1 7RH, UK.
    Faigler, S.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
    Jorissen, A.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium.
    Kervella, P.
    LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190 Meudon, France.
    Mazeh, T.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
    Mowlavi, N.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Panuzzo, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    Sahlmann, J.
    RHEA for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692, Madrid, Spain.
    Shahaf, S.
    Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 7610001, Israel.
    Sozzetti, A.
    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Bauchet, N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    Damerdji, Y.
    CRAAG – Centre de Recherche en Astronomie, Astrophysique et Géophysique, Route de l’Observatoire Bp 63 Bouzareah, 16340 Algiers, Algeria; Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, 4000 Liège, Belgium.
    Gavras, P.
    RHEA for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692, Madrid, Spain.
    Giacobbe, P.
    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Gosset, E.
    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, 4000 Liège, Belgium; F.R.S.-FNRS, Rue d’Egmont 5, 1000 Brussels, Belgium.
    Halbwachs, J.-L.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France.
    Holl, B.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland; Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Lattanzi, M. G.
    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; University of Turin, Department of Physics, Via Pietro Giuria 1, 10125 Torino, Italy.
    Leclerc, N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    Morel, T.
    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, 4000 Liège, Belgium.
    Pourbaix, D.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium; F.R.S.-FNRS, Rue d’Egmont 5, 1000 Brussels, Belgium.
    Re Fiorentin, P.
    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Sadowski, G.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium.
    Ségransan, D.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Siopis, C.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium.
    Teyssier, D.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692, Madrid, Spain.
    Zwitter, T.
    Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana, Slovenia.
    Planquart, L.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium.
    Brown, A. G. A.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
    Vallenari, A.
    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Prusti, T.
    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    de Bruijne, J. H. J.
    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Biermann, M.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Creevey, O. L.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Ducourant, C.
    Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Evans, D. W.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Eyer, L.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Guerra, R.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692, Madrid, Spain.
    Hutton, A.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692, Madrid, Spain.
    Jordi, C.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Klioner, S. A.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Lammers, U. L.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692, Madrid, Spain.
    Lindegren, L.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden.
    Luri, X.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Mignard, F.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Panem, C.
    CNES Centre Spatial de Toulouse, 18 Avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Randich, S.
    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Sartoretti, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    Soubiran, C.
    Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Tanga, P.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Walton, N. A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Bailer-Jones, C. A. L.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Bastian, U.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Drimmel, R.
    INAF – Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Jansen, F.
    European Space Agency, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Katz, D.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 place Jules Janssen, 92190 Meudon, France.
    van Leeuwen, F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Bakker, J.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada 28692 Madrid, Spain.
    Cacciari, C.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Castañeda, J.
    DAPCOM for Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    De Angeli, F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Fabricius, C.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Fouesneau, M.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Frémat, Y.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Galluccio, L.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Guerrier, A.
    CNES Centre Spatial de Toulouse, 18 Avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Heiter, U.
    Observational Astrophysics, Division of Astronomy and Space Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden.
    Masana, E.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Messineo, R.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    Nicolas, C.
    CNES Centre Spatial de Toulouse, 18 Avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Nienartowicz, K.
    Sednai Sàrl, Geneva, Switzerland; Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Pailler, F.
    CNES Centre Spatial de Toulouse, 18 Avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, PO Box 64 00014 Helsinki, Finland.
    Zucker, S.
    Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
    Gaia Data Release 3: Stellar multiplicity, a teaser for the hidden treasure2023Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 674, artikel-id A34Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Context. The Gaia DR3 catalogue contains, for the first time, about 800 000 solutions with either orbital elements or trend parameters for astrometric, spectroscopic, and eclipsing binaries, and combinations of these three.

    Aims. With this paper, we aim to illustrate the huge potential of this large non-single-star catalogue.

    Methods. Using the orbital solutions and models of the binaries, we have built a catalogue of tens of thousands of stellar masses or lower limits thereof, some with consistent flux ratios. Properties concerning the completeness of the binary catalogues are discussed, statistical features of the orbital elements are explained, and a comparison with other catalogues is performed.

    Results. Illustrative applications are proposed for binaries across the Hertzsprung-Russell Diagram (HRD). Binarity is studied in the giant branch and a search for genuine spectroscopic binaries among long-period variables is performed. The discovery of new EL CVn systems illustrates the potential of combining variability and binarity catalogues. Potential compact object companions are presented, mainly white dwarf companions or double degenerates, but one candidate neutron star is also found. Towards the bottom of the main sequence, the orbits of previously suspected binary ultracool dwarfs are determined and new candidate binaries are discovered. The long awaited contribution of Gaia to the analysis of the substellar regime shows the brown dwarf desert around solar-type stars using true rather than minimum masses, and provides new important constraints on the occurrence rates of substellar companions to M dwarfs. Several dozen new exoplanets are proposed, including two with validated orbital solutions and one super-Jupiter orbiting a white dwarf, all being candidates requiring confirmation. Besides binarity, higher order multiple systems are also found.

    Conclusions. By increasing the number of known binary orbits by more than one order of magnitude, Gaia DR3 will provide a rich reservoir of dynamical masses and an important contribution to the analysis of stellar multiplicity.

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  • 27.
    Arildsson, Måns
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Development of a Light Weight L2-Cache Controller2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    An L2 cache is a device that buffers data in fast memory closer to the Central Processing Unit(CPU) in order to deliver its contents with much lower latency than can otherwise be achieved bymain memory. This provides a substantial performance increase in many systems as the memoryinterface is often a bottleneck. The goal of this thesis is to develop a simple L2 cache usingVHDL for Cobham Gaisler’s open source hardware library GRLIB which currently lacks such acore. The outcome of the thesis is the IP core L2C-Lite which will be released in Febuary of 2022 as an addition to GRLIB. L2C-Lite has been integrated into multiple systems and has providedmajor performance gains in applications running under linux as well as other benchmarks. Inaddition, some potential improvements have been identified to further increase the performanceof the cache, as well as improve its usability in systems.

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  • 28.
    Arora, Aman
    et al.
    Department of Geography, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110025, India.
    Arabameri, Alireza
    Department of Geomorphology, Tarbiat Modares University, Jalal Ale Ahmad Highway, Tehran 9821, Iran.
    Pandey, Manish
    University Center for Research & Development (UCRD), Chandigarh University, Mohali 140413, Punjab, India. Department of Civil Engineering, Chandigarh University, Mohali 140413, Punjab, India.
    Siddiqui, Masood A.
    Department of Geography, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi 110025, India.
    Shukla, U.K.
    Center for Advanced Study in Geology, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
    Tien Bui, Dieu
    Institute of Research and Development, Duy Tan University, Da Nang 550000, Viet Nam.
    Mishra, Varun Narayan
    Centre for Climate Change and Water Research, Suresh Gyan Vihar University, Jaipur 302017, Rajasthan, India.
    Bhardwaj, Anshuman
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. School of Geosciences, University of Aberdeen, Meston Building, King's College, Aberdeen AB24 3UE, UK.
    Optimization of state-of-the-art fuzzy-metaheuristic ANFIS-based machine learning models for flood susceptibility prediction mapping in the Middle Ganga Plain, India2021Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 750, artikel-id 141565Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study is an attempt to quantitatively test and compare novel advanced-machine learning algorithms in terms of their performance in achieving the goal of predicting flood susceptible areas in a low altitudinal range, sub-tropical floodplain environmental setting, like that prevailing in the Middle Ganga Plain (MGP), India. This part of the Ganga floodplain region, which under the influence of undergoing active tectonic regime related subsidence, is the hotbed of annual flood disaster. This makes the region one of the best natural laboratories to test the flood susceptibility models for establishing a universalization of such models in low relief highly flood prone areas. Based on highly sophisticated flood inventory archived for this region, and 12 flood conditioning factors viz. annual rainfall, soil type, stream density, distance from stream, distance from road, Topographic Wetness Index (TWI), altitude, slope aspect, slope, curvature, land use/land cover, and geomorphology, an advanced novel hybrid model Adaptive Neuro Fuzzy Inference System (ANFIS), and three metaheuristic models-based ensembles with ANFIS namely ANFIS-GA (Genetic Algorithm), ANFIS-DE (Differential Evolution), and ANFIS-PSO (Particle Swarm Optimization), have been applied for zonation of the flood susceptible areas. The flood inventory dataset, prepared by collected flood samples, were apportioned into 70:30 classes to prepare training and validation datasets. One independent validation method, the Area-Under Receiver Operating Characteristic (AUROC) Curve, and other 11 cut-off-dependent model evaluation metrices have helped to conclude that the ANIFS-GA has outperformed other three models with highest success rate AUC = 0.922 and prediction rate AUC = 0.924. The accuracy was also found to be highest for ANFIS-GA during training (0.886) & validation (0.883). Better performance of ANIFS-GA than the individual models as well as some ensemble models suggests and warrants further study in this topoclimatic environment using other classes of susceptibility models. This will further help establishing a benchmark model with capability of highest accuracy and sensitivity performance in the similar topographic and climatic setting taking assumption of the quality of input parameters as constant.

  • 29.
    Athanasiou, Eleni
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Studies of the orbital background noise and the detector characteristics for the MeVCube mission2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A space camera is a promising candidate to address the non-stop rising interest for astrophysics research in the Compton regime. The MeVCube mission is intended to be launched in 2022, hosting an on-board Compton Camera. To better support the development of the instrument in this early stage, a series of feasibility studies to assess two potential launch orbits were performed. The studies were composed by a series of mission analysis simulations which permitted the characterisation of the orbital environments for the two orbital options. Several sources of background noise to the instrument were identified. The population of trapped protons and trapped electrons were simulated for the periods of Solar Minimum and Solar Maximum, as well as the levels of Galactic Cosmic Ray (GCR) flux. The performance of trade-off studies concluded that an equatorial orbit is more preferable for reducing the influence of background noise. To better estimate the environment effects at the equatorial orbit, the number of particles which can penetrate the detector shielding were simulated. The next step was to perform a series secondary studies whose aim were to simulate the induced current on the electrodes, produced by the interactions occurring within the detector. The actualisation of these simulations required the study of photon interaction with matter, the various Cadmium-Zink-Telluride (CZT) types and the how they operate, and the use of a sophisticated software to perform the appropriate simulations. COMSOL, which allows the method of FEA, was chosen as the tool to perform the simulations. The geometry of the detector voxel was primarily designed in SIEMENS NX. The geometry was inserted into COMSOL, where a number of iterations were performed to finalise the appropriate mesh size, which ensured an accurate representation of the Electric field and the Weighting potential within the detector voxel. The induced current on the electrodes was decided to be calculated via MATLAB. As a verification step it was thought useful to firstly plot the weighting potential of the three electrodes under test; the chosen anode pixel, the steering grid and the cathode. The process revealed a series of numerical errors, most likely introduced by the type of mesh chosen or by the data manipulation process via MATLAB. Significant reduction of the numerical errors would lead to more accurate values for the induced current. Unfortunately, due to time constraints this was a task that was not completed. Solving this problem would be optimal for future studies with MATLAB, as the induced current on the electrodes can be correctly calculated based on charge transport within the detector bulk.

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  • 30.
    Attree, Nicholas
    et al.
    Faculty of Natural Sciences, University of Stirling, UK.
    Kaufmann, Erika
    Faculty of Natural Sciences, University of Stirling, UK. Institute for Space Research Graz, Austrian Academy of Sciences, Austria.
    Hagermann, Axel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Faculty of Natural Sciences, University of Stirling, UK.
    Gas flow in Martian spider formation2021Ingår i: Icarus, ISSN 0019-1035, E-ISSN 1090-2643, Vol. 359, artikel-id 114355Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Martian araneiform terrain, located in the Southern polar regions, consists of features with central pits and radial troughs which are thought to be associated with the solid state greenhouse effect under a CO2 ice sheet. Sublimation at the base of this ice leads to gas buildup, fracturing of the ice and the flow of gas and entrained regolith out of vents and onto the surface. There are two possible pathways for the gas: through the gap between the ice slab and the underlying regolith, as proposed by Kieffer (2007), or through the pores of a permeable regolith layer, which would imply that regolith properties can control the spacing between adjacent spiders, as suggested by Hao et al. (2019). We test this hypothesis quantitatively in order to place constraints on the regolith properties. Based on previously estimated flow rates and thermophysical arguments, we suggest that there is insufficient depth of porous regolith to support the full gas flow through the regolith. By contrast, free gas flow through a regolith–ice gap is capable of supplying the likely flow rates for gap sizes on the order of a centimetre. This size of gap can be opened in the centre of a spider feature by gas pressure bending the overlying ice slab upwards, or by levitating it entirely as suggested in the original Kieffer (2007) model. Our calculations therefore support at least some of the gas flowing through a gap opened between the regolith and ice. Regolith properties most likely still play a role in the evolution of spider morphology, by regolith cohesion controlling the erosion of the central pit and troughs, for example.

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  • 31.
    Auenmüller, Christoph
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Automated Controller Design for a Missile Using Convex Optimization2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The focus of the present master thesis is the automation of an existing controllerdesign for a missile using two aerodynamic actuating systems. The motivation isto evaluate more missile concepts in a shorter period of time.The option used is trimming and linearization of a highly nonlinear missile at specic conditions. According to these conditions, either a two-dimensional operatingpoint grid dened by Mach number and height or three-dimensional operatingpoint grid dened by Mach number, height and angle of attack is generated forthe whole operating range of the missile. The controllers are designed at thesepoints using convex optimization. The convex set denes the pole placement areawhich is constrained by linear matrix inequalities according to the dynamic behaviorof the missile at the operating point conditions. These controllers describea validity area where the missile can be stabilized. This area consists all neighboringoperating points and denes therefore the grid density which can dier atspecic regions of the operating range. Controlling the missile to the target makesit necessary to apply gain-scheduling in order to get the manipulated variable byinterpolation of adjacent operating points. During this blending of the controllersa problem called windup can occur when an actuator is saturated. This mightlead to instability in worst case but can be counteracted by a model-recovery antiwindupnetwork which guarantees stability in the presence of saturation. Thisanti-windup design is automated by an ane linear parameter dependency of thegrid parameters and has the same validity area like the controllers.The whole design was successfully developed and tested in MATLAB/Simulink onmissiles using one or two aerodynamic actuating systems. The controllers have agood performance at small and high acceleration steps and the anti-windup keepsthe missile stable even though the actuators are saturated. Stability and robustnessof the controllers and anti-windup networks was veried as well as an airdefense maneuver where the missile starts at the ground and intercepts a targetat high altitude was successfully simulated for dierent grids and missiles.

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  • 32.
    Augustsson, Rasmus
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Automated process of morphing a CAD geometry based on a measured point cloud2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    As part of the quality process and to assure that the product meets all geometric requirements, the produced part is measured and compared to the nominal geometry definition. If the part deviates outside given tolerances, there is a need to understand the effect on aero performance and mechanical function. Hence, a new analysis model must be created that reflects the produced shape and form of the product. The current procedure for measuring the part is to use white light scanning equipment to analyze the deviation with the scanning software GOM™. The analysis model is then created using Space claim™ and is meshed and analyzed using Ansys™ software. The objective with this thesis is to investigate the capabilities within Siemens NX™ to automate the procedure as there is a need to be more efficient and reduce lead-time.The Design Research Method is used to develop the automated procedure. This is a systematic method that identifies the task, presents possible solutions to that task and then evaluates those solutions. That workflow is repeated until a satisfying solution is found.It is found that it is possible to create an automated procedure in Siemens NX. This automated procedure requires no user interaction while running, so the lead-time is drastically reduced. The automated procedure morphs the nominal geometry to create a new surface with better resemblance to the scanned geometry. About 90% of the original surface area is outside a tolerance of 0.1mm, after the automated procedure the new surface has about 90% of the surface area inside a tolerance of 0.1mm.The limiting factor for the procedure is the skill of the developer and not the capability of the software. Therefore it is thought that the procedure could be improved to create a surface completely inside the specified tolerance, given that a more skilled developer refines the procedure.

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  • 33.
    Avasak, Kalyani
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Institute of Space Systems, University of Stuttgart.
    Mission Analysis and Trajectory optimisation for project CAPE2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Atmospheric reentry is a challenging part of human space ight and planetary entry missions.At the Institute of Space Systems in University of Stuttgart the idea of projectCAPE was conceived in 2012. Project Cubesat Atmospheric Probe for Education aimsto demonstrate the capability of miniaturised technologies of the micro electric plasmathruster, reentry vehicle design and ablative shielding material developed in this institute.The mission scenario is such that the CAPE is being deployed from the InternationalSpace Station and needs to complete the de-orbit of the Service and deorbit module andre-entry of the Atmospheric entry module in less than 1 year. The Cube satellite weighs3.0 kg consisting of a 2+1 unit service design module with solar panels, pulsed plasmapropulsion system of the university of Stuttgart (PETRUS) and a micro atmosphericreentry module (MIRKA-2). This reentry vehicle is unique in its size and weighs 0.5kg. During its reentry phase, it will be subjected to the intense aero-thermal loads at theThermal Protection System front which are absorbed by its ablative heat shield. But thecharacteristics of the re-entry trajectory like the ight path angle, entry velocity and entrypoint greatly determine the survivability against the integral heat load for this ballisticreentry vehicle. Although the success of the mission is considerably higher when having acontrolled reentry, in case of ballistic vehicles it is solely determined by the mission design.The main task is to investigate and develop the optimal re-entry trajectories in thedesign-time phase of mission development for MIRKA-2 vehicle that satises the objectiveof minimizing heat loads and adhering to operational constraints. Thus, the aimof this thesis is to provide a novel solution and optimum trajectory of the de-orbit andre-entry ight to maximize the survivability of the reentry module. The con icting parametersin this mission would be the operational limit of the pulsed plasma thruster andminimum heat loads during reentry ight. The simulation of these trajectories is carriedout in MATLAB using the REENT software developed in the Institute of Space Systems,University of Stuttgart. Its source code is composed in Fortran 77 which is integratedinto MATLAB. A careful mission analysis with the constraints of the capacity of pulsedplasma thruster, impulse provided by the separation mechanism and survivability of thereentry vehicle is carried out to prove the feasibility of this mission. In order to accomplishthe survivability during re-entry the aspects that have been modelled are the ight dynamicsof the satellite, aerodynamic and aero-thermal loads, spacecraft behaviour underthe external loads and local heating process.

  • 34.
    Awad, Mahmoud E.
    et al.
    Department of Geology, Faculty of Science, Al-Azhar University, Nasr City, 11884 Cairo, Egypt. Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain. Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR, Av. de las Palmeras 4, 18100 Armilla, Granada, Spain.
    Borrego-Sánchez, Ana
    Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain. Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR, Av. de las Palmeras 4, 18100 Armilla, Granada, Spain.
    Escamilla-Roa, Elizabeth
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR, Av. de las Palmeras 4, 18100 Armilla, Granada, Spain.
    Hernández-Laguna, Alfonso
    Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR, Av. de las Palmeras 4, 18100 Armilla, Granada, Spain.
    Sainz-Díaz, C. Ignacio
    Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR, Av. de las Palmeras 4, 18100 Armilla, Granada, Spain.
    Modeling of the adsorption of a protein-fragment on kaolinite with potential antiviral activity2020Ingår i: Applied Clay Science, ISSN 0169-1317, E-ISSN 1872-9053, Vol. 199, artikel-id 105865Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work aimed at studying the potentiality of interactions between kaolinite surfaces and a protein-fragment (350–370 amino acid units) extracted from the glycoprotein E1 in the transmembrane domain (TMD) of hepatitis C virus capsid. A computational work was performed for locating the potential electrostatic interaction sites between kaolinite aluminol and siloxane surfaces and the residues of this protein-fragment ligand, monitoring the possible conformational changes. This hydrated neutralized kaolinite/protein-fragment system was simulated by means of molecular modeling based on atomistic force fields based on empirical interatomic potentials and molecular dynamic (MD) simulations. The MD calculations indicated that the studied protein-fragment interacted with the kaolinite surfaces with an exothermic process and structural distortions were observed, particularly with the hydrophilic aluminol surface by favorable adsorption energy. The viral units isolation or trapping by the adsorption on the kaolinite nanoparticles producing structural distortion of the peptide ligands could lead to the blockage of the entry on the receptor and hence a lack of viral activity would be produced. Therefore, these findings with the proposed insights could be an useful information for the next experimental and development studies in the area of discovering inhibitors of the global challenged hepatitis and other pathogenic viruses based on the phyllosilicate surface activity. These MD studies can be extended to other viruses like the COVID-19 interacting with silicate minerals surfaces.

  • 35.
    Axelsson, Katarina
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Studies of auroral processes using optical methods2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The Aurora is a visual manifestation of the complex plasma processes that occur as the solar wind interacts with the Earth’s magnetosphere and ionosphere. Therefore, studies of the aurora can lead to better understanding of the near-Earth space environment and of fundamental physical processes.This thesis focuses on optical studies of the aurora, both ground-based observations using the Auroral Large Imaging System (ALIS) and measurements from instruments onboard the Japanese micro-satellite Reimei. Various properties of the aurora are studied, such as the characteristic energy of precipitating electrons and scale sizes of diffuse auroral structures. Our understanding of the ionospheric physical processes involved in a particular auroral emission is improved using conjugate particle and optical data.Auroral light is a result of radiative transitions between excited states of the ionospheric gases. These excited states are formed either by direct electron impact or by a series of more complicated processes, involving chemical reactions, where part of the energy is converted into auroral light. Studies of auroral emissions can therefore give information about primary particle fluxes, ionospheric composition, and the magnetospheric and ionospheric processes leading to auroral precipitation. One way of deducing the characteristic energy of the precipitating particles is by using intensity ratios of auroral emissions. To be reliable, this method requires a good understanding of the processes involved in the auroral emissions used. The method works well if the measurements are made along the geomagnetic field lines. Using data from ALIS, both in magnetic zenith and off magnetic zenith, this method is tested for angles further away from the direction of the magnetic field lines. The result shows that it is possible to use this technique to deduce the characteristic energy for angles up to 35 degrees away from magnetic zenith.Using ALIS we have also been able to study structures and variations in diffuse aurora. When mapped to the magnetosphere, this provides information about the characteristics of the modulating wave activity in the magnetospheric source region. A statistical study of the scale sizes of diffuse auroral structures was made and the result shows widths and separation between structures of the order of 13-14 km. When mapped to the magnetosphere, this corresponds to 3-4 ion gyro radii for protons with a typical energy of 7 keV. Magnetometer data show that the structures move southward with a speed close to zero in the plasma convection frame. Stationary mirror mode structures in the magnetospheric equatorial plane are a likely explanation for these diffuse auroral structures. In another study we use measured precipitating electron energy spectra to improve our understanding of how the auroral process itself relates to the 427.8 nm auroral emission, which is often used when studying intensity ratios between different emission lines. The 427.8 nm emission is a fairly simple emission to model, with only a few processes involved, but still has some uncertainties, mostly due to the excitation cross section. Simultaneous measurements of the intensity of this emission from ALIS and the intensity and electron flux from Reimei provide a way to evaluate different sets of cross sections in order to find the best fit to the experimental data. It also allows a comparison of the absolute calibration of ALIS and Reimei imagers, improving the possibility to use the space-borne data for other detailed quantitative studies.In order to compare absolute measurements of aurora using different imagers, optical instruments are usually absolute calibrated by exposing them to a calibration light source. In 2011 an intercalibration workshop was held in Sodankylä, Finland, where nine low light sources were compared to the radioactive Fritz Peak reference source. The results were compared with earlier calibration workshop results and show that the sources are fairly stable. Two sources were also calibrated with the calibration standard source at UNIS, Svalbard, and the results show agreement with the calibration workshop in Sodankylä within 15 to 25%. This confirms the quality of the measurements with ALIS and in turn also of the the Reimei imagers.

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  • 36.
    Axelsson, Katarina
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Sergienko, T.
    Swedish Institute of Space Physics / Institutet för rymdfysik.
    Nilsson, H.
    Swedish Institute of Space Physics / Institutet för rymdfysik.
    Brändström, U.
    Swedish Institute of Space Physics / Institutet för rymdfysik.
    Ebihara, Y.
    Research Institute for Sustainable Humanosphere, Kyoto University.
    Asamura, K.
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara.
    Hirahara, M.
    Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo.
    Spatial characteristics of wave-like structures in diffuse aurora obtained using optical observations2012Ingår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 30, nr 12, s. 1693-1701Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present the results of a statistical study using optical images from ALIS (Auroral Large Imaging System) to investigate the spatial and temporal variations of structures in diffuse aurora. Analysis of conjugate Reimei data shows that such fine structures are a result of modulation of high-energy precipitating electrons. Pitch angle diffusion into the loss cone due to interaction of whistler mode waves with plasma sheet electrons is the most feasible mechanism leading to high-energy electron precipitation. This suggests that the fine structure is an indication of modulations of the efficiency of the wave-particle interaction. The scale sizes and variations of these structures, mapped to the magnetosphere, can give us information about the characteristics of the modulating wave activity. We found the scale size of the auroral stripes and the spacing between them to be on average 13-14 km, which corresponds to 3-4 ion gyro radii for protons with an energy of 7 keV. The structures move southward with a speed close to zero in the plasma convection frame.

  • 37.
    Ayala Fernández, Lucía
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Impact of Collision Avoidance Manoeuvres on Large Satellite Constellations2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 38.
    Aygün, Idil
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Development of SoC (System-on-Chip)with EtherCAT Slave for CAESAR Space Robot2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The motivation of the thesis is to develop a System on Chip (SoC) design with the softcore RISC-V toprovide the EtherCAT(Ethernet for Control Automation Technology) slave communication for CAESARspace robot whose backbone communication system bus is provided by EtherCAT protocol. CAESARis a space mission project of Institute of Robotics andMechatronics at DLR and the current concept ofCAESAR’s Joint Control Units (JCU) are desired to improve due to design complexity of the JCU’s electronicunits. In this thesis, the design complexity is reduced with the operation of EtherCAT slave communicationthrough FPGA-based RISC-V IP core instead of using several Digital Signal Processors (DSPs) to utilize fornew concept of the electronic units.The work was performed by following four parts. The first one established a design of RISC-V subsystemwhich provides the configuration of the soft core RISC-V and interconnection with the other moduleson the FPGA design. As a second part, a bridge was designed in VHDL hardware description languageto operate as AXI slave for efficient data transfers and Process Data Interface (PDI) to access the Ether-CAT slave. With the integration of the subsystem and the bridge, the SoC design was performed. In thethird part, the SoC design was tested by the software implementation into the application layer of Ether-CAT slave. Finally, the EtherCAT communication through the SoC designwas validated by EtherCAT master.After the successful tests and the validation, the work shows that the SoC design can be conveniently usedfor the communication system of CAESAR’s Joint Control Units (JCU) by avoiding a complex design.

  • 39.
    Azua-Bustos, Armando
    et al.
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain. Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.
    González-Silva, Carlos
    Facultad de Ciencias, Universidad de Tarapacá, Arica, Chile.
    Fernández-Martínez, Miguel Ángel
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Arenas-Fajardo, Cristián
    Atacama Biotech, Santiago, Chile.
    Fonseca, Ricardo
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Instituto Andaluz de Ciencias de la Tierra (UGR-CSIC), Armilla, Granada, Spain.
    Fernández-Sampedro, Maite
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain.
    Fairén, Alberto G.
    Centro de Astrobiología (CSIC-INTA), Madrid, Spain. Department of Astronomy, Cornell University, Ithaca, NY, USA.
    Zorzano Mier, María-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Aeolian transport of viable microbial life across the Atacama Desert, Chile: Implications for Mars2019Ingår i: Scientific Reports, E-ISSN 2045-2322, Vol. 9, artikel-id 11024Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here we inspect whether microbial life may disperse using dust transported by wind in the Atacama Desert in northern Chile, a well-known Mars analog model. By setting a simple experiment across the hyperarid core of the Atacama we found that a number of viable bacteria and fungi are in fact able to traverse the driest and most UV irradiated desert on Earth unscathed using wind-transported dust, particularly in the later afternoon hours. This finding suggests that microbial life on Mars, extant or past, may have similarly benefited from aeolian transport to move across the planet and find suitable habitats to thrive and evolve.

  • 40.
    Babusiaux, C.
    et al.
    Université Grenoble Alpes, CNRS, IPAG.
    van Leeuwen, F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Barstow, M. A.
    Leicester Institute of Space and Earth Observation and Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK.
    Jordi, C.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Vallenari, A.
    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Bossini, D.
    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Bressan, A.
    SISSA – Scuola Internazionale Superiore di Studi Avanzati, via Bonomea 265, 34136 Trieste, Italy.
    Cantat-Gaudin, T.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain; INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    van Leeuwen, M.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Brown, A. G. A.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
    Prusti, T.
    Science Support Office, Directorate of Science, European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    de Bruijne, J. H. J.
    Science Support Office, Directorate of Science, European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Bailer-Jones, C. A. L.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Biermann, M.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Evans, D. W.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Eyer, L.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Jansen, F.
    Mission Operations Division, Operations Department, Directorate of Science, European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Klioner, S. A.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Lammers, U.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Lindegren, L.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden.
    Luri, X.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Mignard, F.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Panem, C.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Pourbaix, D.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Bruxelles, Belgium; F.R.S.-FNRS, Rue d’Egmont 5, 1000 Bruxelles, Belgium.
    Randich, S.
    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Sartoretti, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Siddiqui, H. I.
    Telespazio Vega UK Ltd for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Soubiran, C.
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Walton, N. A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Arenou, F.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Bastian, U.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Cropper, M.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Drimmel, R.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Katz, D.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Lattanzi, M. G.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Bakker, J.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Cacciari, C.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Castañeda, J.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Chaoul, L.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Cheek, N.
    Serco Gestión de Negocios for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    De Angeli, F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Fabricius, C.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Guerra, R.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Holl, B.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Masana, E.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Messineo, R.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Mowlavi, N.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Nienartowicz, K.
    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Panuzzo, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Portell, J.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Riello, M.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Seabroke, G. M.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Tanga, P.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Thévenin, F.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Gracia-Abril, G.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany; IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Comoretto, G.
    Telespazio Vega UK Ltd for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Garcia-Reinaldos, M.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Teyssier, D.
    Telespazio Vega UK Ltd for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Altmann, M.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany; SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Andrae, R.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Audard, M.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Bellas-Velidis, I.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    Benson, K.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Berthier, J.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Blomme, R.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Burgess, P.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Busso, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Carry, B.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France; IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Cellino, A.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Clementini, G.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Clotet, M.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Creevey, O.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Davidson, M.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
    De Ridder, J.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
    Delchambre, L.
    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, B-4000 Liège, Belgium.
    Dell’Oro, A.
    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Ducourant, C.
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Fernández-Hernández, J.
    ATG Europe for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Fouesneau, M.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Frémat, Y.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Galluccio, L.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    García-Torres, M.
    Área de Lenguajes y Sistemas Informáticos, Universidad Pablo de Olavide, Ctra. de Utrera, km 1. 41013 Sevilla, Spain.
    González-Núñez, J.
    Serco Gestión de Negocios for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; ETSE Telecomunicación, Universidade de Vigo, Campus Lagoas-Marcosende, 36310 Vigo, Spain.
    González-Vidal, J. J.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Gosset, E.
    F.R.S.-FNRS, Rue d’Egmont 5, 1000 Bruxelles, Belgium; Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, B-4000 Liège, Belgium.
    Guy, L. P.
    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland; Large Synoptic Survey Telescope, 950 N. Cherry Avenue, Tucson, AZ 85719, USA.
    Halbwachs, J.-L.
    Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France.
    Hambly, N. C.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
    Harrison, D. L.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambride CB3 0HA, UK.
    Hernández, J.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Hestroffer, D.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Hodgkin, S. T.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Hutton, A.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Jasniewicz, G.
    Laboratoire Univers et Particules de Montpellier, Université Montpellier, Place Eugène Bataillon, CC72, 34095 Montpellier Cedex 05, France.
    Jean-Antoine-Piccolo, A.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Jordan, S.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Korn, A. J.
    Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala, Sweden.
    Krone-Martins, A.
    CENTRA, Universidade de Lisboa, FCUL, Campo Grande, Edif. C8, 1749-016 Lisboa, Portugal.
    Lanzafame, A. C.
    Università di Catania, Dipartimento di Fisica e Astronomia, Sezione Astrofisica, Via S. Sofia 78, 95123 Catania, Italy; INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Lebzelter, T.
    Department of Astrophysics, University of Vienna, Türkenschanzstraße 17, A1180 Vienna, Austria.
    Löffler, W.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Manteiga, M.
    CITIC – Department of Computer Science, University of A Coruña, Campus de Elviña s/n, 15071, A Coruña, Spain; CITIC – Astronomy and Astrophysics, University of A Coruña, Campus de Elviña s/n, 15071, A Coruña, Spain.
    Marrese, P. M.
    INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy; Space Science Data Center – ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Martín-Fleitas, J. M.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Moitinho, A.
    CENTRA, Universidade de Lisboa, FCUL, Campo Grande, Edif. C8, 1749-016 Lisboa, Portugal.
    Mora, A.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Muinonen, K.
    Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland; Finnish Geospatial Research Institute FGI, Geodeetinrinne 2, 02430 Masala, Finland.
    Osinde, J.
    Isdefe for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Pancino, E.
    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy; Space Science Data Center – ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Pauwels, T.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Petit, J.-M.
    Institut UTINAM UMR6213, CNRS, OSU THETA Franche-Comté Bourgogne, Université Bourgogne Franche-Comté, 25000 Besançon, France.
    Recio-Blanco, A.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Richards, P. J.
    STFC, Rutherford Appleton Laboratory, Harwell, Didcot OX11 0QX, UK.
    Rimoldini, L.
    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Robin, A. C.
    Institut UTINAM UMR6213, CNRS, OSU THETA Franche-Comté Bourgogne, Université Bourgogne Franche-Comté, 25000 Besançon, France.
    Sarro, L. M.
    Departamento de Inteligencia Artificial, UNED, c/ Juan del Rosal 16, 28040 Madrid, Spain.
    Siopis, C.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Bruxelles, Belgium.
    Smith, M.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Sozzetti, A.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Süveges, M.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Torra, J.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    van Reeven, W.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Abbas, U.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Abreu Aramburu, A.
    Elecnor Deimos Space for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Accart, S.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Aerts, C.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium; Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands.
    Altavilla, G.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy; INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy; Space Science Data Center – ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Álvarez, M. A.
    CITIC – Department of Computer Science, University of A Coruña, Campus de Elviña s/n, 15071, A Coruña, Spain.
    Alvarez, R.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Alves, J.
    Department of Astrophysics, University of Vienna, Türkenschanzstraße 17, A1180 Vienna, Austria.
    Anderson, R. I.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland; European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany.
    Andrei, A. H.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France; ON/MCTI-BR, Rua Gal. José Cristino 77, Rio de Janeiro, CEP 20921-400, Brazil; OV/UFRJ-BR, Ladeira Pedro Antônio 43, Rio de Janeiro, CEP 20080-090, Brazil.
    Anglada Varela, E.
    ATG Europe for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Antiche, E.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Antoja, T.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain; Science Support Office, Directorate of Science, European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Arcay, B.
    CITIC – Department of Computer Science, University of A Coruña, Campus de Elviña s/n, 15071, A Coruña, Spain.
    Astraatmadja, T. L.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road, NW, Washington, DC 20015-1305, USA.
    Bach, N.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Baker, S. G.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Balaguer-Núñez, L.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Balm, P.
    Telespazio Vega UK Ltd for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Barache, C.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Barata, C.
    CENTRA, Universidade de Lisboa, FCUL, Campo Grande, Edif. C8, 1749-016 Lisboa, Portugal.
    Barbato, D.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy; Università di Torino, Dipartimento di Fisica, via Pietro Giuria 1, 10125 Torino, Italy.
    Barblan, F.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Barklem, P. S.
    Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala, Sweden.
    Barrado, D.
    Departamento de Astrofísica, Centro de Astrobiología (CSIC-INTA), ESA-ESAC, Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Madrid, Spain.
    Barros, M.
    CENTRA, Universidade de Lisboa, FCUL, Campo Grande, Edif. C8, 1749-016 Lisboa, Portugal.
    Bartholomé Muñoz, L.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Bassilana, J.-L.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Becciani, U.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Bellazzini, M.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Berihuete, A.
    Departamento de Estadística, Universidad de Cádiz, Calle República Árabe Saharawi s/n, 11510 Puerto Real, Spain.
    Bertone, S.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy; SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France; Astronomical Institute Bern University, Sidlerstrasse 5, 3012 Bern, Switzerland.
    Bianchi, L.
    EURIX S.r.l., Corso Vittorio Emanuele II 61, 10128 Torino, Italy.
    Bienaymé, O.
    Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France.
    Blanco-Cuaresma, S.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland; Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France; Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge MA 02138, USA.
    Boch, T.
    Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France.
    Boeche, C.
    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Bombrun, A.
    HE Space Operations BV for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Borrachero, R.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Bouquillon, S.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Bourda, G.
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Bragaglia, A.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Bramante, L.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Breddels, M. A.
    Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Brouillet, N.
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Brüsemeister, T.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Brugaletta, E.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Bucciarelli, B.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Burlacu, A.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Busonero, D.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Butkevich, A. G.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Buzzi, R.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Caffau, E.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Cancelliere, R.
    Department of Computer Sciences, University of Turin, Corso Svizzera 185, 10149 Torino, Italy.
    Cannizzaro, G.
    Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands; SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584CA Utrecht, The Netherlands.
    Carballo, R.
    Departamento de Matemática Aplicada y Ciencias de la Computación, Universidad de Cantabria, ETS Ingenieros de Caminos, Canales y Puertos, Avda. de los Castros s/n, 39005 Santander, Spain.
    Carlucci, T.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Carrasco, J. M.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Casamiquela, L.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Castellani, M.
    INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy.
    Castro-Ginard, A.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Charlot, P.
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Chemin, L.
    Unidad de Astronomía, Universidad de Antofagasta, Avenida Angamos 601, Antofagasta 1270300, Chile.
    Chiavassa, A.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Cocozza, G.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Costigan, G.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
    Cowell, S.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Crifo, F.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Crosta, M.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Crowley, C.
    HE Space Operations BV for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Cuypers, J.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Dafonte, C.
    CITIC – Department of Computer Science, University of A Coruña, Campus de Elviña s/n, 15071, A Coruña, Spain.
    Damerdji, Y.
    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, B-4000 Liège, Belgium; CRAAG – Centre de Recherche en Astronomie, Astrophysique et Géophysique, Route de l’Observatoire Bp 63 Bouzareah 16340 Alger, Algeria.
    Dapergolas, A.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    David, P.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    David, M.
    University of Antwerp, Onderzoeksgroep Toegepaste Wiskunde, Middelheimlaan 1, 2020 Antwerp, Belgium.
    de Laverny, P.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    De Luise, F.
    INAF – Osservatorio Astronomico d’Abruzzo, Via Mentore Maggini, 64100 Teramo, Italy.
    De March, R.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    de Martino, D.
    INAF – Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    de Souza, R.
    Instituto de Astronomia, Geofìsica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão 1226, Cidade Universitaria, 05508-900 São Paulo, Brazil.
    de Torres, A.
    HE Space Operations BV for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Debosscher, J.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
    del Pozo, E.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Delbo, M.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Delgado, A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Delgado, H. E.
    Departamento de Inteligencia Artificial, UNED, c/ Juan del Rosal 16, 28040 Madrid, Spain.
    Diakite, S.
    Institut UTINAM UMR6213, CNRS, OSU THETA Franche-Comté Bourgogne, Université Bourgogne Franche-Comté, 25000 Besançon, France.
    Diener, C.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Distefano, E.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Dolding, C.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Drazinos, P.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Durán, J.
    Isdefe for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Edvardsson, B.
    Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala, Sweden.
    Enke, H.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Eriksson, K.
    Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala, Sweden.
    Esquej, P.
    RHEA for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Eynard Bontemps, G.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Fabre, C.
    ATOS for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Fabrizio, M.
    INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy; Space Science Data Center – ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Faigler, S.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
    Falcão, A. J.
    UNINOVA – CTS, Campus FCT-UNL, Monte da Caparica, 2829-516 Caparica, Portugal.
    Farràs Casas, M.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Federici, L.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Fedorets, G.
    Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland.
    Fernique, P.
    Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France.
    Figueras, F.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Filippi, F.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Findeisen, K.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Fonti, A.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Fraile, E.
    RHEA for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Fraser, M.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; School of Physics, O’Brien Centre for Science North, University College Dublin, Belfield, Dublin 4, Ireland.
    Frézouls, B.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Gai, M.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Galleti, S.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Garabato, D.
    CITIC – Department of Computer Science, University of A Coruña, Campus de Elviña s/n, 15071, A Coruña, Spain.
    García-Sedano, F.
    Departamento de Inteligencia Artificial, UNED, c/ Juan del Rosal 16, 28040 Madrid, Spain.
    Garofalo, A.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy; Dipartimento di Fisica e Astronomia, Università di Bologna, Via Piero Gobetti 93/2, 40129 Bologna, Italy.
    Garralda, N.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Gavel, A.
    Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala, Sweden.
    Gavras, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France; National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece; Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Gerssen, J.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Geyer, R.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Giacobbe, P.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Gilmore, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Girona, S.
    Barcelona Supercomputing Center – Centro Nacional de Supercomputación, c/ Jordi Girona 29, Ed. Nexus II, 08034 Barcelona, Spain.
    Giuffrida, G.
    INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy; Space Science Data Center – ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Glass, F.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Gomes, M.
    CENTRA, Universidade de Lisboa, FCUL, Campo Grande, Edif. C8, 1749-016 Lisboa, Portugal.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland.
    Gueguen, A.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France; Max Planck Institute for Extraterrestrial Physics, High Energy Group, Gießenbachstraße, 85741 Garching, Germany.
    Guerrier, A.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Guiraud, J.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Gutié, R.
    Telespazio Vega UK Ltd for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Haigron, R.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Hatzidimitriou, D.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece; Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Hauser, M.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Haywood, M.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Heiter, U.
    Department of Physics and Astronomy, Division of Astronomy and Space Physics, Uppsala University, Box 516, 75120 Uppsala, Sweden.
    Helmi, A.
    Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Heu, J.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Hilger, T.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Hobbs, D.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden.
    Hofmann, W.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Holland, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Huckle, H. E.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK.
    Hypki, A.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands; Astronomical Observatory Institute, Faculty of Physics, Adam Mickiewicz University, Słoneczna 36, 60-286 Poznań, Poland.
    Icardi, V.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Janßen, K.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Jevardat de Fombelle, G.
    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Jonker, P. G.
    Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands; SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584CA Utrecht, The Netherlands.
    Juhász, Á. L.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary; Eötvös Loránd University, Egyetem tér 1-3, H-1053 Budapest, Hungary.
    Julbe, F.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Karampelas, A.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece; American Community Schools of Athens, 129 Aghias Paraskevis Ave. & Kazantzaki Street, Halandri, 15234 Athens, Greece.
    Kewley, A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Klar, J.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Kochoska, A.
    Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana, Slovenia; Villanova University, Department of Astrophysics and Planetary Science, 800 E Lancaster Avenue, Villanova PA 19085, USA.
    Kohley, R.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Kolenberg, K.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium; Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge MA 02138, USA; Physics Department, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
    Kontizas, M.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Kontizas, E.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    Koposov, S. E.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
    Kordopatis, G.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Kostrzewa-Rutkowska, Z.
    Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands; SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584CA Utrecht, The Netherlands.
    Koubsky, P.
    Astronomical Institute, Academy of Sciences of the Czech Republic, Fričova 298, 25165 Ondřejov, Czech Republic.
    Lambert, S.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Lanza, A. F.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Lasne, Y.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Lavigne, J.-B.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Le Fustec, Y.
    Telespazio for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Le Poncin-Lafitte, C.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Lebreton, Y.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France; Institut de Physique de Rennes, Université de Rennes 1, 35042 Rennes, France.
    Leccia, S.
    INAF – Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Leclerc, N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Lecoeur-Taibi, I.
    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Lenhardt, H.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Leroux, F.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Liao, S.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy; Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Rd, 200030 Shanghai, PR China; School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 100049, PR China.
    Licata, E.
    EURIX S.r.l., Corso Vittorio Emanuele II 61, 10128 Torino, Italy.
    Lindstrøm, H. E. P.
    Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen Ø, Denmark; DXC Technology, Retortvej 8, 2500 Valby, Denmark.
    Lister, T. A.
    Las Cumbres Observatory, 6740 Cortona Drive Suite 102, Goleta, CA 93117, USA.
    Livanou, E.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Lobel, A.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    López, M.
    Departamento de Astrofísica, Centro de Astrobiología (CSIC-INTA), ESA-ESAC, Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Madrid, Spain.
    Managau, S.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Mann, R. G.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
    Mantelet, G.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Marchal, O.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Marchant, J. M.
    Astrophysics Research Institute, Liverpool John Moores University, 146 Brownlow Hill, Liverpool L3 5RF, UK.
    Marconi, M.
    INAF – Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Marinoni, S.
    INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy; Space Science Data Center – ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Marschalkó, G.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary; Baja Observatory of University of Szeged, Szegedi út III/70, 6500 Baja, Hungary.
    Marshall, D. J.
    Laboratoire AIM, IRFU/Service d’Astrophysique – CEA/DSM – CNRS – Université Paris Diderot, Bât. 709, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France.
    Martino, M.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Marton, G.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Mary, N.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Massari, D.
    Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Matijevič, G.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Mazeh, T.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
    McMillan, P. J.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden.
    Messina, S.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Michalik, D.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, 22100 Lund, Sweden.
    Millar, N. R.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Molina, D.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Molinaro, R.
    INAF – Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Molnár, L.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Montegriffo, P.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Mor, R.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Morbidelli, R.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Morel, T.
    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, B-4000 Liège, Belgium.
    Morris, D.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
    Mulone, A. F.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Muraveva, T.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Musella, I.
    INAF – Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Nelemans, G.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium; Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands.
    Nicastro, L.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Noval, L.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    O’Mullane, W.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; Large Synoptic Survey Telescope, 950 N. Cherry Avenue, Tucson, AZ 85719, USA.
    Ordénovic, C.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Ordóñez-Blanco, D.
    Department of Astronomy, University of Geneva, Chemin d’Ecogia 16, 1290 Versoix, Switzerland.
    Osborne, P.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Pagani, C.
    Leicester Institute of Space and Earth Observation and Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK.
    Pagano, I.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Pailler, F.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Palacin, H.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Palaversa, L.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Panahi, A.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
    Pawlak, M.
    Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland; Faculty of Mathematics and Physics, Institute of Theoretical Physics, Charles University, Prague, Czech Republic.
    Piersimoni, A. M.
    INAF – Osservatorio Astronomico d’Abruzzo, Via Mentore Maggini, 64100 Teramo, Italy.
    Pineau, F.-X.
    Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, 67000 Strasbourg, France.
    Plachy, E.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Plum, G.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Poggio, E.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy; Università di Torino, Dipartimento di Fisica, via Pietro Giuria 1, 10125 Torino, Italy.
    Poujoulet, E.
    AKKA for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Prša, A.
    Villanova University, Department of Astrophysics and Planetary Science, 800 E Lancaster Avenue, Villanova PA 19085, USA.
    Pulone, L.
    INAF – Osservatorio Astronomico di Roma, Via di Frascati 33, 00078 Monte Porzio Catone, Italy.
    Racero, E.
    Serco Gestión de Negocios for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Ragaini, S.
    INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Rambaux, N.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Ramos-Lerate, M.
    Vitrociset Belgium for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Regibo, S.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
    Reylé, C.
    Institut UTINAM UMR6213, CNRS, OSU THETA Franche-Comté Bourgogne, Université Bourgogne Franche-Comté, 25000 Besançon, France.
    Riclet, F.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Ripepi, V.
    INAF – Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Riva, A.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Rivard, A.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Rixon, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Roegiers, T.
    HE Space Operations BV for ESA/ESTEC, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Roelens, M.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Romero-Gómez, M.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Rowell, N.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
    Royer, F.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Ruiz-Dern, L.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Sadowski, G.
    Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Bruxelles, Belgium.
    Sagristà Sellés, T.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Sahlmann, J.
    European Space Astronomy Centre (ESA/ESAC), Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; Space Telescope Science Institute, 3700 San Martin Drive, Baltimore MD 21218, USA.
    Salgado, J.
    QUASAR Science Resources for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Salguero, E.
    ATG Europe for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Sanna, N.
    INAF – Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Santana-Ros, T.
    Astronomical Observatory Institute, Faculty of Physics, Adam Mickiewicz University, Słoneczna 36, 60-286 Poznań, Poland.
    Sarasso, M.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Savietto, H.
    Fork Research, Rua do Cruzado Osberno, Lt. 1, 9 esq., Lisboa, Portugal.
    Schultheis, M.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Sciacca, E.
    INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy.
    Segol, M.
    APAVE SUDEUROPE SAS for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Segovia, J. C.
    Serco Gestión de Negocios for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Ségransan, D.
    Department of Astronomy, University of Geneva, Chemin des Maillettes 51, 1290 Versoix, Switzerland.
    Shih, I-C.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Siltala, L.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain; Nordic Optical Telescope, Rambla José Ana Fernández Pérez 7, 38711 Breña Baja, Spain.
    Silva, A. F.
    CENTRA, Universidade de Lisboa, FCUL, Campo Grande, Edif. C8, 1749-016 Lisboa, Portugal.
    Smart, R. L.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Smith, K. W.
    Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany.
    Solano, E.
    Departamento de Astrofísica, Centro de Astrobiología (CSIC-INTA), ESA-ESAC, Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Madrid, Spain; Spanish Virtual Observatory, Spain.
    Solitro, F.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Sordo, R.
    INAF – Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Soria Nieto, S.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Souchay, J.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Spagna, A.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Spoto, F.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France; IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Stampa, U.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Steele, I. A.
    Astrophysics Research Institute, Liverpool John Moores University, 146 Brownlow Hill, Liverpool L3 5RF, UK.
    Steidelmüller, H.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Stephenson, C. A.
    Telespazio Vega UK Ltd for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Stoev, H.
    Fundación Galileo Galilei – INAF, Rambla José Ana Fernández Pérez 7, 38712 Breña Baja, Santa Cruz de Tenerife, Spain.
    Suess, F. F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Surdej, J.
    Institut d’Astrophysique et de Géophysique, Université de Liège, 19c Allée du 6 Août, B-4000 Liège, Belgium.
    Szabados, L.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Szegedi-Elek, E.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Tapiador, D.
    INSA for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; Departamento de Arquitectura de Computadores y Automática, Facultad de Informática, Universidad Complutense de Madrid, C/ Prof. José García Santesmases s/n, 28040 Madrid, Spain.
    Taris, F.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Tauran, G.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Taylor, M. B.
    H H Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL, UK.
    Teixeira, R.
    Instituto de Astronomia, Geofìsica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão 1226, Cidade Universitaria, 05508-900 São Paulo, Brazil.
    Terrett, D.
    STFC, Rutherford Appleton Laboratory, Harwell, Didcot OX11 0QX, UK.
    Teyssandier, P.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 avenue de l’Observatoire 75014 Paris, France.
    Thuillot, W.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 av. Denfert-Rochereau, 75014 Paris, France.
    Titarenko, A.
    Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Torra Clotet, F.
    Institut d’Estudis Espacials de Catalunya (IEEC), Gran Capita 2-4, 08034 Barcelona, Spain.
    Turon, C.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Ulla, A.
    Applied Physics Department, Universidade de Vigo, 36310 Vigo, Spain.
    Utrilla, E.
    Aurora Technology for ESA/ESAC, Camino bajo del Castillo s/n, Urbanización Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Uzzi, S.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Vaillant, M.
    Thales Services for CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Valentini, G.
    INAF – Osservatorio Astronomico d’Abruzzo, Via Mentore Maggini, 64100 Teramo, Italy.
    Valette, V.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    van Elteren, A.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
    Van Hemelryck, E.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Vaschetto, M.
    ALTEC SpA, Corso Marche 79, 10146 Torino, Italy.
    Vecchiato, A.
    INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy.
    Veljanoski, J.
    Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Viala, Y.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Vicente, D.
    Barcelona Supercomputing Center – Centro Nacional de Supercomputación, c/ Jordi Girona 29, Ed. Nexus II, 08034 Barcelona, Spain.
    Vogt, S.
    HE Space Operations BV for ESA/ESTEC, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    von Essen, C.
    Stellar Astrophysics Centre, Aarhus University, Department of Physics and Astronomy, 120 Ny Munkegade, Building 1520, DK-8000 Aarhus C, Denmark.
    Voss, H.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Votruba, V.
    Astronomical Institute, Academy of Sciences of the Czech Republic, Fričova 298, 25165 Ondřejov, Czech Republic.
    Voutsinas, S.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK.
    Walmsley, G.
    CNES Centre Spatial de Toulouse, 18 avenue Edouard Belin, 31401 Toulouse Cedex 9, France.
    Weiler, M.
    Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Wertz, O.
    Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany.
    Wevers, T.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; Department of Astrophysics/IMAPP, Radboud University, PO Box 9010, 6500 GL Nijmegen, The Netherlands.
    Wyrzykowski, Ł.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK; Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.
    Yoldas, A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK.
    Žerjal, M.
    Research School of Astronomy and AstrophysFaculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana, Slovenia; ics, Australian National University, Canberra, ACT 2611 Australia.
    Ziaeepour, H.
    Institut UTINAM UMR6213, CNRS, OSU THETA Franche-Comté Bourgogne, Université Bourgogne Franche-Comté, 25000 Besançon, France.
    Zorec, J.
    Sorbonne Universités, UPMC Univ. Paris 6 et CNRS, UMR 7095, Institut d’Astrophysique de Paris, 98 bis bd. Arago, 75014 Paris, France.
    Zschocke, S.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstraße 13, 01062 Dresden, Germany.
    Zucker, S.
    Department of Geosciences, Tel Aviv University, Tel Aviv 6997801, Israel.
    Zurbach, C.
    Laboratoire Univers et Particules de Montpellier, Université Montpellier, Place Eugène Bataillon, CC72, 34095 Montpellier Cedex 05, France.
    Zwitter, T.
    Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana, Slovenia.
    Observational Hertzsprung-Russell diagrams2018Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 16, nr A10Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry and photometry are unprecedented. Aims. We highlight the power of the Gaia DR2 in studying many fine structures of the Hertzsprung-Russell diagram (HRD). Gaia allows us to present many different HRDs, depending in particular on stellar population selections. We do not aim here for completeness in terms of types of stars or stellar evolutionary aspects. Instead, we have chosen several illustrative examples. Methods. We describe some of the selections that can be made in Gaia DR2 to highlight the main structures of the Gaia HRDs. We select both field and cluster (open and globular) stars, compare the observations with previous classifications and with stellar evolutionary tracks, and we present variations of the Gaia HRD with age, metallicity, and kinematics. Late stages of stellar evolution such as hot subdwarfs, post-AGB stars, planetary nebulae, and white dwarfs are also analysed, as well as low-mass brown dwarf objects. Results. The Gaia HRDs are unprecedented in both precision and coverage of the various Milky Way stellar populations and stellar evolutionary phases. Many fine structures of the HRDs are presented. The clear split of the white dwarf sequence into hydrogen and helium white dwarfs is presented for the first time in an HRD. The relation between kinematics and the HRD is nicely illustrated. Two different populations in a classical kinematic selection of the halo are unambiguously identified in the HRD. Membership and mean parameters for a selected list of open clusters are provided. They allow drawing very detailed cluster sequences, highlighting fine structures, and providing extremely precise empirical isochrones that will lead to more insight in stellar physics. Conclusions. Gaia DR2 demonstrates the potential of combining precise astrometry and photometry for large samples for studies in stellar evolution and stellar population and opens an entire new area for HRD-based studies.

  • 41.
    Bagnulo, Stefano
    et al.
    Armagh Observatory & Planetarium, College Hill, Armagh, BT61 9DG, UK.
    Gray, Zuri
    Armagh Observatory & Planetarium, College Hill, Armagh, BT61 9DG, UK; Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking RH5 6NT, UK.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, PO Box 64, FI-00014 University of Helsinki, Finland.
    Cellino, Alberto
    INAF—Osservatorio Astrofisico di Torino, I-10025 Pino Torinese, Italy.
    Kolokolova, Ludmilla
    Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA.
    Muinonen, Karri
    Department of Physics, PO Box 64, FI-00014 University of Helsinki, Finland.
    Muñoz, Olga
    Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomia s/n, E-18008 Granada, Spain.
    Opitom, Cyrielle
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ, UK.
    Penttilä, Antti
    Department of Physics, PO Box 64, FI-00014 University of Helsinki, Finland.
    Snodgrass, Colin
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ, UK.
    Optical Spectropolarimetry of Binary Asteroid Didymos-Dimorphos before and after the DART Impact2023Ingår i: Astrophysical Journal Letters, ISSN 2041-8205, E-ISSN 2041-8213, Vol. 945, nr 2, artikel-id L38Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have monitored the Didymos-Dimorphos binary asteroid in spectropolarimetric mode in the optical range before and after the DART impact. The ultimate goal was to obtain constraints on the characteristics of the ejected dust for modeling purposes. Before impact, Didymos exhibited a linear polarization rapidly increasing with phase angle, reaching a level of ∼5% in the blue and ∼4.5% in the red. The shape of the polarization spectrum was anticorrelated with that of its reflectance spectrum, which appeared typical of an S-class asteroid. After impact, the level of polarization dropped by about 1 percentage point (pp) in the blue band and about 0.5 pp in the red band, then continued to linearly increase with phase angle, with a slope similar to that measured prior to impact. The polarization spectra, once normalized by their values at an arbitrary wavelength, show very little or no change over the course of all observations before and after impact. The lack of any remarkable change in the shape of the polarization spectrum after impact suggests that the way in which polarization varies with wavelength depends on the composition of the scattering material, rather than on its structure, be this a surface or a debris cloud.

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  • 42.
    Bailer-Jones, C. A.L.
    et al.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany.
    Teyssier, D.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Delchambre, L.
    Institut d Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium.
    Ducourant, C.
    Laboratoire d Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Garabato, D.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Hatzidimitriou, D.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece; National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    Klioner, S. A.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstrabe 13, 01062 Dresden, Germany.
    Rimoldini, L.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland.
    Bellas-Velidis, I.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    Carballo, R.
    Dpto. de Matemática Aplicada y Ciencias de la Computación, Univ. de Cantabria, ETS Ingenieros de Caminos, Canales y Puertos, Avda. de los Castros s/n, 39005 Santander, Spain.
    Carnerero, M. I.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Diener, C.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Fouesneau, M.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany.
    Galluccio, L.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Gavras, P.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Krone-Martins, A.
    CENTRA, Faculdade de Ciências, Universidade de Lisboa, Edif. C8, Campo Grande, 1749-016 Lisboa, Portugal; Department of Informatics, Donald Bren School of Information and Computer Sciences, University of California, Irvine, 5226 Donald Bren Hall, 92697-3440 CA, Irvine, USA.
    Raiteri, C. M.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Teixeira, R.
    Instituto de Astronomia, Geofìsica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão, 1226, Cidade Universitaria, 05508-900 São Paulo, SP, Brazil.
    Brown, A. G.A.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
    Vallenari, A.
    INAF Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Prusti, T.
    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    De Bruijne, J. H.J.
    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Arenou, F.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Babusiaux, C.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France; Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France.
    Biermann, M.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Creevey, O. L.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Evans, D. W.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Eyer, L.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Guerra, R.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Hutton, A.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Jordi, C.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Lammers, U. L.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Lindegren, L.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43 22100 Lund, Sweden.
    Luri, X.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Mignard, F.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Panem, C.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Pourbaix, D.
    Institut d Astronomie et d Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium; F.R.S.-FNRS, Rue d Egmont 5, 1000 Brussels, Belgium.
    Randich, S.
    INAF Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Sartoretti, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Soubiran, C.
    Laboratoire d Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Tanga, P.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Walton, N. A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Bastian, U.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Drimmel, R.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Jansen, F.
    European Space Agency, Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Katz, D.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Lattanzi, M. G.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; University of Turin, Department of Physics, Via Pietro Giuria 1, 10125 Torino, Italy.
    Van Leeuwen, F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Bakker, J.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Cacciari, C.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Castañeda, J.
    DAPCOM for Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    De Angeli, F.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Fabricius, C.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Frémat, Y.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Guerrier, A.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Heiter, U.
    Observational Astrophysics, Division of Astronomy and Space Physics, Department of Physics and Astronomy, Uppsala University, Box 516 751 20 Uppsala, Sweden.
    Masana, E.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Messineo, R.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    Mowlavi, N.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Nicolas, C.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Nienartowicz, K.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland; Sednai Sàrl, Geneva, Switzerland.
    Pailler, F.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Panuzzo, P.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Riclet, F.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Roux, W.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Seabroke, G. M.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Sordo, R.
    INAF Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Thévenin, F.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Gracia-Abril, G.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany; Gaia DPAC Project Office, ESAC, Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Portell, J.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Altmann, M.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany; SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France.
    Andrae, R.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany.
    Audard, M.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland; Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Benson, K.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Berthier, J.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 Av. Denfert-Rochereau, 75014 Paris, France.
    Blomme, R.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Burgess, P. W.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Busonero, D.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Busso, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Cánovas, H.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Carry, B.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Cellino, A.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Cheek, N.
    Serco Gestión de Negocios for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Clementini, G.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Damerdji, Y.
    Institut d Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium; CRAAG Centre de Recherche en Astronomie, Astrophysique et Géophysique, Route de l Observatoire Bp 63 Bouzareah, 16340 Algiers, Algeria.
    Davidson, M.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ UK.
    De Teodoro, P.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Nuñez Campos, M.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Dell Oro, A.
    INAF Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Esquej, P.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Fernández-Hernández, J.
    ATG Europe for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Fraile, E.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    García-Lario, P.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Gosset, E.
    Institut d Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium; F.R.S.-FNRS, Rue d Egmont 5, 1000 Brussels, Belgium.
    Haigron, R.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Halbwachs, J. L.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Hambly, N. C.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ UK.
    Harrison, D. L.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK; Kavli Institute for Cosmology Cambridge, Institute of Astronomy, Madingley Road, Cambridge, CB3 0HA UK.
    Hernández, J.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Hestroffer, D.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 Av. Denfert-Rochereau, 75014 Paris, France.
    Hodgkin, S. T.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Holl, B.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland; Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Janen, K.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Jevardat De Fombelle, G.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Jordan, S.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Lanzafame, A. C.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy; Dipartimento di Fisica e Astronomia Ettore Majorana, Università di Catania, Via S. Sofia 64, 95123 Catania, Italy.
    Löffler, W.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Marchal, O.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Marrese, P. M.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy; Space Science Data Center ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Moitinho, A.
    CENTRA, Faculdade de Ciências, Universidade de Lisboa, Edif. C8, Campo Grande, 1749-016 Lisboa, Portugal.
    Muinonen, K.
    Department of Physics, University of Helsinki, PO Box 64 00014 Helsinki, Finland; Finnish Geospatial Research Institute FGI, Geodeetinrinne 2, 02430 Masala, Finland.
    Osborne, P.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Pancino, E.
    INAF Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy; Space Science Data Center ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Pauwels, T.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Recio-Blanco, A.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Reylé, C.
    Institut UTINAM CNRS UMR6213, Université Bourgogne Franche-Comté, OSU THETA Franche-Comté Bourgogne, Observatoire de Besançon, BP1615, 25010 Besançon Cedex, France.
    Riello, M.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Roegiers, T.
    HE Space Operations BV for European Space Agency (ESA), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Rybizki, J.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany.
    Sarro, L. M.
    Dpto. de Inteligencia Artificial, UNED, c/ Juan del Rosal 16, 28040 Madrid, Spain.
    Siopis, C.
    Institut d Astronomie et d Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium.
    Smith, M.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Sozzetti, A.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Utrilla, E.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Van Leeuwen, M.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Abbas, U.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Ábrahám, P.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary; ELTE Eötvös Loránd University, Institute of Physics, 1117, Pázmány Péter sétány 1A, Budapest, Hungary.
    Abreu Aramburu, A.
    ATG Europe for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Aerts, C.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany; Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium; Department of Astrophysics/IMAPP, Radboud University, PO Box 9010 6500 GL Nijmegen, The Netherlands.
    Aguado, J. J.
    Dpto. de Inteligencia Artificial, UNED, c/ Juan del Rosal 16, 28040 Madrid, Spain.
    Ajaj, M.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Aldea-Montero, F.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Altavilla, G.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy; Space Science Data Center ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Álvarez, M. A.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Alves, J.
    University of Vienna, Department of Astrophysics, Trkenschanzstrabe 17, 1180 Vienna, Austria.
    Anderson, R. I.
    Institute of Physics, Laboratory of Astrophysics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Observatoire de Sauverny, 1290 Versoix, Switzerland.
    Anglada Varela, E.
    ATG Europe for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Antoja, T.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Baines, D.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Baker, S. G.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Balaguer-Núñez, L.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Balbinot, E.
    Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Balog, Z.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany; Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Barache, C.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France.
    Barbato, D.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Barros, M.
    CENTRA, Faculdade de Ciências, Universidade de Lisboa, Edif. C8, Campo Grande, 1749-016 Lisboa, Portugal.
    Barstow, M. A.
    School of Physics and Astronomy/Space Park Leicester, University of Leicester, University Road, Leicester, LE1 7RH UK.
    Bartolomé, S.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Bassilana, J. L.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Bauchet, N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Becciani, U.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Bellazzini, M.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Berihuete, A.
    Depto. Estadística e Investigación Operativa, Universidad de Cádiz, Avda. República Saharaui s/n, 11510 Puerto Real, Cádiz, Spain.
    Bernet, M.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Bertone, S.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Center for Research and Exploration in Space Science and Technology, University of Maryland Baltimore County, 1000, Hilltop Circle Baltimore, MD, USA; GSFC Goddard Space Flight Center, Code 698, 8800 Greenbelt Rd, 20771 MD, Greenbelt, USA.
    Bianchi, L.
    EURIX S.r.l., Corso Vittorio Emanuele II 61, 10128, Torino, Italy.
    Binnenfeld, A.
    Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, 6997801 Israel.
    Blanco-Cuaresma, S.
    Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS 15, Cambridge, MA, 02138 USA.
    Boch, T.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Bombrun, A.
    HE Space Operations BV for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Bossini, D.
    Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP, Rua das Estrelas, 4150-762 Porto, Portugal.
    Bouquillon, S.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France; LFCA/DAS, Universidad de Chile, CNRS, Casilla 36-D, Santiago, Chile.
    Bragaglia, A.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Bramante, L.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    Breedt, E.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Bressan, A.
    SISSA Scuola Internazionale Superiore di Studi Avanzati, Via Bonomea 265, 34136 Trieste, Italy.
    Brouillet, N.
    Laboratoire d Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Brugaletta, E.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Bucciarelli, B.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; University of Turin, Department of Physics, Via Pietro Giuria 1, 10125 Torino, Italy.
    Burlacu, A.
    Telespazio for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Butkevich, A. G.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Buzzi, R.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Caffau, E.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Cancelliere, R.
    University of Turin, Department of Computer Sciences, Corso Svizzera 185, 10149 Torino, Italy.
    Cantat-Gaudin, T.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany; Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Carlucci, T.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France.
    Carrasco, J. M.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Casamiquela, L.
    Laboratoire d Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France; GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Castellani, M.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy.
    Castro-Ginard, A.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
    Chaoul, L.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Charlot, P.
    Laboratoire d Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Chemin, L.
    Centro de Astronomía CITEVA, Universidad de Antofagasta, Avenida Angamos 601, Antofagasta, 1270300 Chile.
    Chiaramida, V.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    Chiavassa, A.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Chornay, N.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Comoretto, G.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; DLR Gesellschaft für Raumfahrtanwendungen (GfR) mbH, Münchener Strabe 20, 82234 Webling, Germany.
    Contursi, G.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Cooper, W. J.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Centre for Astrophysics Research, University of Hertfordshire, College Lane, AL10 9AB Hatfield, UK.
    Cornez, T.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Cowell, S.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Crifo, F.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Cropper, M.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Crosta, M.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; University of Turin, Mathematical Department G. Peano, Via Carlo Alberto 10, 10123 Torino, Italy.
    Crowley, C.
    HE Space Operations BV for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Dafonte, C.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Dapergolas, A.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    David, P.
    IMCCE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Univ. Lille, 77 Av. Denfert-Rochereau, 75014 Paris, France.
    De Laverny, P.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    De Luise, F.
    INAF Osservatorio Astronomico d Abruzzo, Via Mentore Maggini, 64100 Teramo, Italy.
    De March, R.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    De Ridder, J.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
    De Souza, R.
    Instituto de Astronomia, Geofìsica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão, 1226, Cidade Universitaria, 05508-900 São Paulo, SP, Brazil.
    De Torres, A.
    HE Space Operations BV for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Del Peloso, E. F.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Del Pozo, E.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Delbo, M.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Delgado, A.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Delisle, J. B.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Demouchy, C.
    APAVE SUDEUROPE SAS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Dharmawardena, T. E.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany.
    Diakite, S.
    Mésocentre de calcul de Franche-Comté, Université de Franche-Comté, 16 Route de Gray, 25030 Besançon Cedex, France.
    Distefano, E.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Dolding, C.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Enke, H.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Fabre, C.
    ATOS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Fabrizio, M.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy; Space Science Data Center ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Faigler, S.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv, 6997801 Israel.
    Fedorets, G.
    Department of Physics, University of Helsinki, PO Box 64 00014 Helsinki, Finland; Astrophysics Research Centre, School of Mathematics and Physics, Queen s University Belfast, Belfast, BT7 1NN UK.
    Fernique, P.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France; Centre de Données Astronomiques de Strasbourg, Strasbourg, France.
    Figueras, F.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Fournier, Y.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Fouron, C.
    Telespazio for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Fragkoudi, F.
    Institute for Computational Cosmology, Department of Physics, Durham University, Durham, DH1 3LE UK; European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany; Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Strabe 1, 85748 Garching, Germany.
    Gai, M.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Garcia-Gutierrez, A.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Garcia-Reinaldos, M.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    García-Torres, M.
    Data Science and Big Data Lab, Pablo de Olavide University, 41013 Seville, Spain.
    Garofalo, A.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Gavel, A.
    Observational Astrophysics, Division of Astronomy and Space Physics, Department of Physics and Astronomy, Uppsala University, Box 516 751 20 Uppsala, Sweden.
    Gerlach, E.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstrabe 13, 01062 Dresden, Germany.
    Geyer, R.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstrabe 13, 01062 Dresden, Germany.
    Giacobbe, P.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Gilmore, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Girona, S.
    Barcelona Supercomputing Center (BSC), Plaça Eusebi Güell 1-3, 08034 Barcelona, Spain.
    Giuffrida, G.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy.
    Gomel, R.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv, 6997801 Israel.
    Gomez, A.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    González-Núñez, J.
    Serco Gestión de Negocios for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; ETSE Telecomunicación, Universidade de Vigo, Campus Lagoas-Marcosende, 36310 Vigo, Galicia, Spain.
    González-Santamaría, I.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    González-Vidal, J. J.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, PO Box 64 00014 Helsinki, Finland.
    Guillout, P.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Guiraud, J.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Gutiérrez-Sánchez, R.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Guy, L. P.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland; Vera C. Rubin Observatory, 950 N. Cherry Avenue, Tucson, AZ, 85719 USA.
    Hauser, M.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany; TRUMPF Photonic Components GmbH, Lise-Meitner-Strabe 13, 89081 Ulm, Germany.
    Haywood, M.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Helmer, A.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Helmi, A.
    Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Sarmiento, M. H.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Hidalgo, S. L.
    IAC Instituto de Astrofisica de Canarias, Via Láctea s/n, 38200 La Laguna S.C., Tenerife, Spain; Department of Astrophysics, University of La Laguna, Via Láctea s/n, 38200 La Laguna S.C., Tenerife, Spain.
    Hilger, T.
    National Observatory of Athens, I. Metaxa and Vas. Pavlou, Palaia Penteli, 15236 Athens, Greece.
    Håadczuk, N.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, The Netherlands.
    Hobbs, D.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43 22100 Lund, Sweden.
    Holland, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Huckle, H. E.
    Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT UK.
    Jardine, K.
    Radagast Solutions, Simon Vestdijkpad 24, 2321 WD Leiden, The Netherlands.
    Jasniewicz, G.
    Laboratoire Univers et Particules de Montpellier, CNRS Université Montpellier, Place Eugène Bataillon, CC72, 34095 Montpellier Cedex 05, France.
    Jean-Antoine Piccolo, A.
    CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 1401 Toulouse Cedex 9, France.
    Jiménez-Arranz, Ó.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Juaristi Campillo, J.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Julbe, F.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Karbevska, L.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland; Université de Caen Normandie, Côte de Nacre Boulevard Maréchal Juin, 14032 Caen, France.
    Kervella, P.
    LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190 Meudon, France.
    Khanna, S.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands.
    Kontizas, M.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Kordopatis, G.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Korn, A. J.
    Observational Astrophysics, Division of Astronomy and Space Physics, Department of Physics and Astronomy, Uppsala University, Box 516 751 20 Uppsala, Sweden.
    Kóspál, Á.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany; Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary; ELTE Eötvös Loránd University, Institute of Physics, 1117, Pázmány Péter sétány 1A, Budapest, Hungary.
    Kostrzewa-Rutkowska, Z.
    Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands; SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands.
    Kruszyåska, K.
    Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.
    Kun, M.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Laizeau, P.
    Scalian for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Lambert, S.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France.
    Lanza, A. F.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Lasne, Y.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Le Campion, J. F.
    Laboratoire d Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, Allée Geoffroy Saint-Hilaire, 33615 Pessac, France.
    Lebreton, Y.
    LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190 Meudon, France; Université Rennes, CNRS, IPR (Institut de Physique de Rennes) UMR 6251, 35000 Rennes, France.
    Lebzelter, T.
    University of Vienna, Department of Astrophysics, Trkenschanzstrabe 17, 1180 Vienna, Austria.
    Leccia, S.
    INAF Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Leclerc, N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Lecoeur-Taibi, I.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland.
    Liao, S.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai, 200030 PR China; University of Chinese Academy of Sciences, No. 19(A) Yuquan Road, Shijingshan District, Beijing, 100049 PR China.
    Licata, E. L.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Lindstrøm, H. E.P.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen , Denmark; DXC Technology, Retortvej 8, 2500 Valby, Denmark.
    Lister, T. A.
    Las Cumbres Observatory, 6740, Cortona Drive Suite 102, Goleta, CA, 93117 USA.
    Livanou, E.
    Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, 15783 Athens, Greece.
    Lobel, A.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium.
    Lorca, A.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Loup, C.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Madrero Pardo, P.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Magdaleno Romeo, A.
    Telespazio for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Managau, S.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Mann, R. G.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ UK.
    Manteiga, M.
    CIGUS CITIC, Department of Nautical Sciences and Marine Engineering, University of A Coruña, Paseo de Ronda 51, 15071 A Coruña, Spain.
    Marchant, J. M.
    Astrophysics Research Institute, Liverpool John Moores University, 146 Brownlow Hill, Liverpool, L3 5RF UK.
    Marconi, M.
    INAF Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Marcos, J.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Marcos Santos, M. M.S.
    Serco Gestión de Negocios for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Marín Pina, D.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Marinoni, S.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy; Space Science Data Center ASI, Via del Politecnico SNC, 00133 Roma, Italy.
    Marocco, F.
    IPAC, Mail Code 100-22, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125 USA.
    Marshall, D. J.
    IRAP, Université de Toulouse, CNRS, UPS, CNES, 9 Av. Colonel Roche, BP 44346, 31028 Toulouse Cedex 4, France.
    Martin Polo, L.
    Serco Gestión de Negocios for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Martín-Fleitas, J. M.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Marton, G.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Mary, N.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Masip, A.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Massari, D.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Mastrobuono-Battisti, A.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Mazeh, T.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv, 6997801 Israel.
    McMillan, P. J.
    Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43 22100 Lund, Sweden.
    Messina, S.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Michalik, D.
    European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands.
    Millar, N. R.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Mints, A.
    Leibniz Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany.
    Molina, D.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Molinaro, R.
    INAF Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Molnár, L.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary; ELTE Eötvös Loránd University, Institute of Physics, 1117, Pázmány Péter sétány 1A, Budapest, Hungary; MTA CSFK Lendület Near-Field Cosmology Research Group, Konkoly Observatory, MTA Research Centre for Astronomy and Earth Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Monari, G.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Monguió, M.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Montegriffo, P.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Montero, A.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Mor, R.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Mora, A.
    Aurora Technology for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Morbidelli, R.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Morel, T.
    Institut d Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium.
    Morris, D.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ UK.
    Muraveva, T.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Murphy, C. P.
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Musella, I.
    INAF Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Nagy, Z.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Noval, L.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Ocaña, F.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; Departmento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, 28040 Madrid, Spain.
    Ogden, A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Ordenovic, C.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Osinde, J. O.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Pagani, C.
    School of Physics and Astronomy/Space Park Leicester, University of Leicester, University Road, Leicester, LE1 7RH UK.
    Pagano, I.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Palaversa, L.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK; Ruer Boškovic Institute, Bijenička Cesta 54, 10000 Zagreb, Croatia.
    Palicio, P. A.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Pallas-Quintela, L.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Panahi, A.
    School of Physics and Astronomy, Tel Aviv University, Tel Aviv, 6997801 Israel.
    Payne-Wardenaar, S.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Peñalosa Esteller, X.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Penttilä, A.
    Department of Physics, University of Helsinki, PO Box 64 00014 Helsinki, Finland.
    Pichon, B.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Piersimoni, A. M.
    INAF Osservatorio Astronomico d Abruzzo, Via Mentore Maggini, 64100 Teramo, Italy.
    Pineau, F. X.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Plachy, E.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary; ELTE Eötvös Loránd University, Institute of Physics, 1117, Pázmány Péter sétány 1A, Budapest, Hungary; MTA CSFK Lendület Near-Field Cosmology Research Group, Konkoly Observatory, MTA Research Centre for Astronomy and Earth Sciences, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Plum, G.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Poggio, E.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy; Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Prša, A.
    Villanova University, Department of Astrophysics and Planetary Science, 800 E Lancaster Avenue, Villanova, PA, 19085 USA.
    Pulone, L.
    INAF Osservatorio Astronomico di Roma, Via Frascati 33, 00078 Monte Porzio Catone, Roma, Italy.
    Racero, E.
    Serco Gestión de Negocios for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; Departmento de Física de la Tierra y Astrofísica, Universidad Complutense de Madrid, 28040 Madrid, Spain.
    Ragaini, S.
    INAF Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Piero Gobetti 93/3, 40129 Bologna, Italy.
    Rainer, M.
    INAF Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy; INAF Osservatorio Astronomico di Brera, via E. Bianchi, 46, 23807 Merate, LC, Italy.
    Ramos, P.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain; Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France.
    Ramos-Lerate, M.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Re Fiorentin, P.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Regibo, S.
    Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
    Richards, P. J.
    STFC, Rutherford Appleton Laboratory, Harwell, Didcot, OX11 0QX UK.
    Rios Diaz, C.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Ripepi, V.
    INAF Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli, Italy.
    Riva, A.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Rix, H. W.
    Max Planck Institute for Astronomy, Knigstuhl 17, 69117 Heidelberg, Germany.
    Rixon, G.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Robichon, N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Robin, A. C.
    Institut UTINAM CNRS UMR6213, Université Bourgogne Franche-Comté, OSU THETA Franche-Comté Bourgogne, Observatoire de Besançon, BP1615, 25010 Besançon Cedex, France.
    Robin, C.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Roelens, M.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Rogues, H. R.O.
    APAVE SUDEUROPE SAS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Rohrbasser, L.
    Department of Astronomy, University of Geneva, Chemin d Ecogia 16, 1290 Versoix, Switzerland.
    Romero-Gómez, M.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Rowell, N.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ UK.
    Royer, F.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Ruz Mieres, D.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Rybicki, K. A.
    Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.
    Sadowski, G.
    Institut d Astronomie et d Astrophysique, Université Libre de Bruxelles CP 226, Boulevard du Triomphe, 1050 Brussels, Belgium.
    Sáez Núñez, A.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Sagristà Sellés, A.
    Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12-14, 69120 Heidelberg, Germany.
    Sahlmann, J.
    RHEA for European Space Agency (ESA), Camino bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Salguero, E.
    ATG Europe for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Samaras, N.
    Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium; Charles University, Faculty of Mathematics and Physics, Astronomical Institute of Charles University, V Holesovickach 2, 18000 Prague, Czech Republic.
    Sanchez Gimenez, V.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Sanna, N.
    INAF Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, 50125 Firenze, Italy.
    Santoveña, R.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Sarasso, M.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Schultheis, M.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Sciacca, E.
    INAF Osservatorio Astrofisico di Catania, Via S. Sofia 78, 95123 Catania, Italy.
    Segol, M.
    APAVE SUDEUROPE SAS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Segovia, J. C.
    Serco Gestión de Negocios for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain.
    Ségransan, D.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Semeux, D.
    ATOS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Shahaf, S.
    Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 7610001 Israel.
    Siddiqui, H. I.
    Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Princeton, NJ, 08544 USA.
    Siebert, A.
    Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 11 Rue de l Université, 67000 Strasbourg, France; Centre de Données Astronomiques de Strasbourg, Strasbourg, France.
    Siltala, L.
    Department of Physics, University of Helsinki, PO Box 64 00014 Helsinki, Finland.
    Silvelo, A.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Slezak, E.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Slezak, I.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Smart, R. L.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Snaith, O. N.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Solano, E.
    Departamento de Astrofísica, Centro de Astrobiología (CSIC-INTA), ESA-ESAC, Camino Bajo del Castillo s/n., 28692 Villanueva de la Cañada, Madrid, Spain.
    Solitro, F.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    Souami, D.
    LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 Place Jules Janssen, 92190 Meudon, France; naXys, University of Namur, Rempart de la Vierge, 5000 Namur, Belgium.
    Souchay, J.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France.
    Spagna, A.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Spina, L.
    INAF Osservatorio astronomico di Padova, Vicolo Osservatorio 5, 35122 Padova, Italy.
    Spoto, F.
    Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS 15, Cambridge, MA, 02138 USA.
    Steele, I. A.
    Astrophysics Research Institute, Liverpool John Moores University, 146 Brownlow Hill, Liverpool, L3 5RF UK.
    Steidelmüller, H.
    Lohrmann Observatory, Technische Universität Dresden, Mommsenstrabe 13, 01062 Dresden, Germany.
    Stephenson, C. A.
    Telespazio UK S.L. for European Space Agency (ESA), Camino Bajo del Castillo, s/n, Urbanizacion Villafranca del Castillo, Villanueva de la Cañada, 28692 Madrid, Spain; CGI Deutschland B.V. & Co. KG, Mornewegstr. 30, 64293 Darmstadt, Germany.
    Süveges, M.
    Institute of Global Health, University of Geneva, Geneva, Switzerland.
    Surdej, J.
    Institut d Astrophysique et de Géophysique, Université de Liège, 19c, Allée du 6 Août, 4000 Liège, Belgium; Astronomical Observatory Institute, Faculty of Physics, Adam Mickiewicz University, Poznan Poland.
    Szabados, L.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Szegedi-Elek, E.
    Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), MTA Centre of Excellence, Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary.
    Taris, F.
    SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, 61 Avenue de l Observatoire, 75014 Paris, France.
    Taylor, M. B.
    H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL UK.
    Tolomei, L.
    ALTEC S.p.a, Corso Marche, 79, 10146 Torino, Italy.
    Tonello, N.
    Barcelona Supercomputing Center (BSC), Plaça Eusebi Güell 1-3, 08034 Barcelona, Spain.
    Torra, F.
    DAPCOM for Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Torra, J.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Torralba Elipe, G.
    CIGUS CITIC Department of Computer Science and Information Technologies, University of A Coruña, Campus de Elviña s/n, A Coruña, 15071 Spain.
    Trabucchi, M.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland; Department of Physics and Astronomy G. Galilei, University of Padova, Vicolo dell Osservatorio 3, 35122 Padova, Italy.
    Tsounis, A. T.
    CERN, Esplanade des Particules 1, PO Box 1211, Geneva, Switzerland.
    Turon, C.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Ulla, A.
    Applied Physics Department, Universidade de Vigo, 36310 Vigo, Spain.
    Unger, N.
    Department of Astronomy, University of Geneva, Chemin Pegasi 51, 1290 Versoix, Switzerland.
    Vaillant, M. V.
    Thales Services for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Van Dillen, E.
    APAVE SUDEUROPE SAS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Van Reeven, W.
    Association of Universities for Research in Astronomy, 1331 Pennsylvania Ave. NW, Washington, DC, 20004 USA.
    Vanel, O.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Vecchiato, A.
    INAF Osservatorio Astrofisico di Torino, Via Osservatorio 20, 10025 Pino Torinese, TO, Italy.
    Viala, Y.
    GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France.
    Vicente, D.
    Barcelona Supercomputing Center (BSC), Plaça Eusebi Güell 1-3, 08034 Barcelona, Spain.
    Voutsinas, S.
    Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh, EH9 3HJ UK.
    Weiler, M.
    Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain.
    Wevers, T.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK; European Southern Observatory, Alonso de Córdova 3107, Casilla 19, Santiago, Chile.
    Wyrzykowski, Ł.
    Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warszawa, Poland.
    Yoldas, A.
    Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA UK.
    Yvard, P.
    APAVE SUDEUROPE SAS for CNES Centre Spatial de Toulouse, 18 Avenue douard Belin, 31401 Toulouse Cedex 9, France.
    Zhao, H.
    Université Côte d Azur, Observatoire de la Côte d Azur, CNRS, Laboratoire Lagrange, Bd de l Observatoire, CS 34229, 06304 Nice Cedex 4, France.
    Zorec, J.
    Sorbonne Université, CNRS, UMR7095, Institut d Astrophysique de Paris, 98bis Bd. Arago, 75014 Paris, France.
    Zucker, S.
    Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, 6997801 Israel.
    Zwitter, T.
    Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica 19, 1000 Ljubljana, Slovenia.
    Gaia Data Release 3: The extragalactic content2023Ingår i: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 674, artikel-id A41Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Gaia Galactic survey mission is designed and optimized to obtain astrometry, photometry, and spectroscopy of nearly two billion stars in our Galaxy. Yet as an all-sky multi-epoch survey, Gaia also observes several million extragalactic objects down to a magnitude of G 21 mag. Due to the nature of the Gaia onboard-selection algorithms, these are mostly point-source-like objects. Using data provided by the satellite, we have identified quasar and galaxy candidates via supervised machine learning methods, and estimate their redshifts using the low resolution BP/RP spectra. We further characterise the surface brightness profiles of host galaxies of quasars and of galaxies from pre-defined input lists. Here we give an overview of the processing of extragalactic objects, describe the data products in Gaia DR3, and analyse their properties. Two integrated tables contain the main results for a high completeness, but low purity (50-70%), set of 6.6 million candidate quasars and 4.8 million candidate galaxies. We provide queries that select purer sub-samples of these containing 1.9 million probable quasars and 2.9 million probable galaxies (both 95% purity). We also use high quality BP/RP spectra of 43 thousand high probability quasars over the redshift range 0.05-4.36 to construct a composite quasar spectrum spanning restframe wavelengths from 72 1000 nm.

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  • 43.
    Baker, Mark
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Optimization of CHIMS2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The CHopper (Comet Hopper) was a proposal for a NASA mission to visit comet 46P/Wirtanen. A time of flight ion and neutral mass spectrometer (CHIMS) was developed especially for the proposed mission and was to be mounted on the Chopper spacecraft. CHIMS was to establish the composition and isotopic ratios of the comet's volatile components. Since NASA selected the InSight mission, CHIMS had been proposed for other missions: LIFE, Life Investigation For Enceladus, a low-cost sample return mission to Enceladus and Castalia, an ESA medium-sized mission to explore the Main Comet Belt. CHIMS was in need of fine tuning; the scientific demand of having accurate detection efficiency, combined with high performance make it necessary to rigorously test and calibrate instruments to operate at their optimum level. The goal of this work is to improve the performance of the ion source by applying simulation and optimization techniques to the CHIMS lab prototype. The results show a positive outcome, and propose a number of future modifications that should help obtain the desired results for any future missions.

  • 44.
    Baker, Niklas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Feasibility and design of miniaturized Control Moment Gyroscope for a 3-axis stabilized Micro Satellite2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In this thesis, a feasibility study will be conducted in order to determine if the usage of acontrol moment gyroscope is a possibility for a micro satellite as its attitude control. Thegoal is to conclude if gyroscopes are suitable replacements for the current reaction wheelswhich are acting as the attitude control for the satellite. In the first part of the thesis thegeneral function of the control moment gyroscope and three different types of arrangementsare displayed with all their respective advantages and disadvantages. Then one ofthem will be designed to fit within the restrictions of 1U. The full design of the pyramidconfiguration was chosen due to its compact size and spherical angular momentum envelope.The full design contains all the components such as motors, flywheels, mounts,frame, screws etc. which provide a cost estimate which is a huge input in determiningthe feasibility of this thesis. In the future the manufacture of the pyramid configurablecontrol moment gyroscopes shall be tested in the future with a more advanced steeringlaw in order to determine the full potential of the attitude control system.

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  • 45.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Ejemalm, Johnny
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kuhn, Thomas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Molin, Sven
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Johansson, Jonny
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, EISLAB.
    Westerberg, Lars-Göran
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Masters Programs in Space Science and Engineering in Northern Sweden2017Konferensbidrag (Refereegranskat)
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  • 46.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kuhn, Thomas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Ejemalm, Johnny
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Enmark, Anita
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    de Oliviera, Élcio Jeronimo
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Persson, Olle
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Sadeghi, Soheil
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    The influence of international student projects on learning and study environment among the national and international space students2020Ingår i: NU2020 — Hållbart lärande: Abstractbok, Sveriges universitets- och högskoleförbund (SUHF) , 2020, s. 74-75Konferensbidrag (Refereegranskat)
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  • 47.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kuhn, Thomas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laufer, Rene
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Development of a competence ecosystem for the future space workforce: strategies, practices and recommendations from international master programs in northern Sweden2022Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 197, s. 46-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Requirements from the global labor market have substantially changed in recent years. Graduate and post-graduate students with excellent subject knowledge, deep understanding of modern working methods, technicaland higher-order thinking, engineering intuition and problem-solving skills are in great demand. They should also have professional skills such as well-developed abilities in communication and teamwork, usually in an international work environment. This review discusses the advantages of multidisciplinary study environment, educational strategies such as student-oriented teaching, project-based learning with its applicability to a“real-world” setting, active learning techniques, development of entrepreneurial skills, lessons learned and best practices from the international Master Program in Spacecraft Design and the Joint Master Program in SpaceScience and Technology – SpaceMaster at Luleå University of Technology in northern Sweden. The importance of complementarity between formal, informal and non-formal learning methods for science and engineering studentshas been specifically highlighted. Connections to the world of work, through active industry involvementin the education in a systematic way, e.g. External Advisory Board, shared services and facilities, joint projectsand supervision of Master and PhD students, is recognised as a key success factor for professional training. A structural combination of modern pedagogical tools, strategic partnership with industry, business entities, academic partners and up-to-date multidisciplinary labs creates the conceptual framework for a CompetenceEcosystem for fostering a new generation of space scientists and engineers.

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  • 48.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kuhn, Thomas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laufer, René
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Development of a Competence Ecosystem for the Future Space Workforce: Strategies, Practices and Recommendations from International Masterprograms in Northern Sweden2021Ingår i: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, International Astronautical Federation (IAF) , 2021, artikel-id 65175Konferensbidrag (Refereegranskat)
    Abstract [en]

    Requirements from the global labor market have substantially changed in recent years. Graduate and postgraduate students with excellent subject knowledge, deep understanding of modern working methods, technical and higher-order thinking, engineering intuition and problem-solving skills are in great demand. They should also have professional skills such as well-developed abilities in communication and teamwork, usually in an international work environment. This review discusses the advantages of multidisciplinary study environment, educational strategies such as student-oriented teaching, project-based learning with its applicability to a "real-world" setting, active learning techniques, development of entrepreneurial skills, lessons learned and best practices from the international Master Program in Spacecraft Design and the Joint Master Program in Space Science and Technology – SpaceMaster at Luleå University of Technology in northern Sweden. The importance of complementarity between formal, informal and non-formal learning methods for science and engineering students has been specifically highlighted. Connections to the world of work, through active industry involvement in the education in a systematic way, e.g. External Advisory Board, shared services and facilities, joint projects and supervision of Master and PhD students, is recognised as a key success factor for professional training. A structural combination of modern pedagogical tools, strategic partnership with industry, business entities, academic partners and up-to-date multidisciplinary labs creates the conceptual framework for a Competence Ecosystem for fostering a new generation of space scientists and engineers.

  • 49.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Osepian, A.
    Polar Geophysical Institute, Halturina 15, 183 023 Murmansk, Russia.
    Dalin, P.
    Swedish Institute of Space Physics, Rymdcampus 1, 981 92 Kiruna, Sweden.
    Kirkwood, S.
    Swedish Institute of Space Physics, Rymdcampus 1, 981 92 Kiruna, Sweden.
    Electron density profiles in the quiet lower ionosphere based on the results of modeling and experimental data2012Ingår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 30, nr 9, s. 1345-1360Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The theoretical PGI (Polar Geophysical Institute) model for the quiet lower ionosphere has been applied for computing the ionization rate and electron density profiles in the summer and winter D-region at solar zenith angles less than 80° and larger than 99° under steady state conditions. In order to minimize possible errors in estimation of ionization rates provided by solar electromagnetic radiation and to obtain the most exact values of electron density, each wavelength range of the solar spectrum has been divided into several intervals and the relations between the solar radiation intensity at these wavelengths and the solar activity index F10.7 have been incorporated into the model. Influence of minor neutral species (NO, H2O, O, O3) concentrations on the electron number density at different altitudes of the sunlit quiet D-region has been examined. The results demonstrate that at altitudes above 70 km, the modeled electron density is most sensitive to variations of nitric oxide concentration. Changes of water vapor concentration in the whole altitude range of the mesosphere influence the electron density only in the narrow height interval 73–85 km. The effect of the change of atomic oxygen and ozone concentration is the least significant and takes place only below 70 km. 

    Model responses to changes of the solar zenith angle, solar activity (low–high) and season (summer–winter) have been considered. Modeled electron density profiles have been evaluated by comparison with experimental profiles available from the rocket measurements for the same conditions. It is demonstrated that the theoretical model for the quiet lower ionosphere is quite effective in describing variations in ionization rate, electron number density and effective recombination coefficient as functions of solar zenith angle, solar activity and season. The model may be used for solving inverse tasks, in particular, for estimations of nitric oxide concentration in the mesosphere.

  • 50.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Osepian, Aleftina
    Polar Geophysical Institute, Murmansk.
    Dalin, Peter
    Swedish Institute of Space Physics / Institutet för rymdfysik.
    Influence of water vapour on the height distribution of positive ions, effective recombination coefficient and ionisation balance in the quiet lower ionosphere2014Ingår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 32, s. 207-222Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mesospheric water vapour concentration effects on the ion composition and electron density in the lower ionosphere under quiet geophysical conditions were examined. Water vapour is an important compound in the mesosphere and the lower thermosphere that affects ion composition due to hydrogen radical production and consequently modifies the electron number density. Recent lower-ionosphere investigations have primarily concentrated on the geomagnetic disturbance periods. Meanwhile, studies on the electron density under quiet conditions are quite rare. The goal of this study is to contribute to a better understanding of the ionospheric parameter responses to water vapour variability in the quiet lower ionosphere. By applying a numerical D region ion chemistry model, we evaluated efficiencies for the channels forming hydrated cluster ions from the NO+ and O2+ primary ions (i.e. NO+.H2O and O2+.H2O, respectively), and the channel forming H+(H2O)nproton hydrates from water clusters at different altitudes using profiles with low and high water vapour concentrations. Profiles for positive ions, effective recombination coefficients and electrons were modelled for three particular cases using electron density measurements obtained during rocket campaigns. It was found that the water vapour concentration variations in the mesosphere affect the position of both the Cl2+ proton hydrate layer upper border, comprising the NO+(H2O)nand O2+(H2O)nhydrated cluster ions, and the Cl1+ hydrate cluster layer lower border, comprising the H+(H2O)npure proton hydrates, as well as the numerical cluster densities. The water variations caused large changes in the effective recombination coefficient and electron density between altitudes of 75 and 87 km. However, the effective recombination coefficient, αeff, and electron number density did not respond even to large water vapour concentration variations occurring at other altitudes in the mesosphere. We determined the water vapour concentration upper limit at altitudes between 75 and 87 km, beyond which the water vapour concentration ceases to influence the numerical densities of Cl2+ and Cl1+, the effective recombination coefficient and the electron number density in the summer ionosphere. This water vapour concentration limit corresponds to values found in the H2O-1 profile that was observed in the summer mesosphere by the Upper Atmosphere Research Satellite (UARS). The electron density modelled using the H2O-1 profile agreed well with the electron density measured in the summer ionosphere when the measured profiles did not have sharp gradients. For sharp gradients in electron and positive ion number densities, a water profile that can reproduce the characteristic behaviour of the ionospheric parameters should have an inhomogeneous height distribution of water vapour.

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