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  • 1.
    Ahmed, Naeem
    et al.
    Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia, UKM, Bangi, 43600, Selangor, Malaysia; Molecular Electrochemistry Laboratory, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 610054, China.
    Masood, Asad
    Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia, UKM, Bangi, 43600, Selangor, Malaysia.
    Mumtaz, Rubab
    Department of Physics, Quaid-e-Azam University, Islamabad, Pakistan.
    Wee, M. F. Mohd Razip
    Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia, UKM, Bangi, 43600, Selangor, Malaysia.
    Chan, Kok Meng
    Petroliam Nasional Berhad, PETRONAS Twin Towers, KLCC, Kuala Lumpur, 50088, Malaysia.
    Patra, Anuttam
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Siow, Kim S.
    Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia, UKM, Bangi, 43600, Selangor, Malaysia.
    Quad-atmospheric Pressure Plasma Jet (q-APPJ) Treatment of Chilli Seeds to Stimulate Germination2024In: Plasma chemistry and plasma processing, ISSN 0272-4324, E-ISSN 1572-8986, Vol. 44, no 1, p. 509-522Article in journal (Refereed)
  • 2.
    Bader, Alexander
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Ion Temperature Anisotropies in the Venus Plasma Environment2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Velocity distributions are a key to understanding the interplay between particles and waves in a plasma. Any deviation from a Maxwellian distribution may be unstable and result in wave generation. Using data from the ion mass spectrometer IMA (Ion Mass Analyzer) and the magnetometer MAG on-board Venus Express,  ion distributions in the plasma environment of Venus are studied. The focus lies on temperature anisotropy, that is, the difference between the ion temperature parallel and perpendicular to the background magnetic field. This study presents spatial maps of the average ratio between the perpendicular temperature  and parallel temperature , both for proton and heavy ions (atomic oxygen, molecularoxygen and carbon dioxide). Furthermore average values of  and  are calculated for different spatial areas around Venus. The results show that proton  and  are nearly equal in the solar wind. At the bow shock and in the magnetosheath, the ratio  increases to provide conditions favoring mirror mode wave generation. An even higher anisotropy is found in the magnetotail with  for both protons and heavy ions.

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  • 3.
    Bader, Alexander
    et al.
    Luleå University of Technology. Swedish Institute of Space Physics, Kiruna, Sweden.
    Stenberg Weiser, G.
    Swedish Institute of Space Physics, Kiruna, Sweden.
    André, M.
    Swedish Institute of Space Physics, Uppsala, Sweden.
    Wieser, M.
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Futaana, Y.
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Persson, M.
    Swedish Institute of Space Physics, Kiruna, Sweden. Department of Physics, Umeå Universitet, Umeå, Sweden.
    Nilsson, H.
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Zhang, T.L.
    Space Research Institute, Austrian Academy of Science, Graz, Austria.
    Proton Temperature Anisotropies in the Plasma Environment of Venus2019In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 124, no 5, p. 3312-3330Article in journal (Refereed)
    Abstract [en]

    Velocity distribution functions (VDFs) are a key to understanding the interplay between particles and waves in a plasma. Any deviation from an isotropic Maxwellian distribution may be unstable and result in wave generation. Using data from the ion mass spectrometer IMA (Ion Mass Analyzer) and the magnetometer (MAG) onboard Venus Express, we study proton distributions in the plasma environment of Venus. We focus on the temperature anisotropy, that is, the ratio between the proton temperature perpendicular (T⊥) and parallel (T‖) to the background magnetic field. We calculate average values of T⊥ and T‖ for different spatial areas around Venus. In addition we present spatial maps of the average of the two temperatures and of their average ratio. Our results show that the proton distributions in the solar wind are quite isotropic, while at the bow shock stronger perpendicular than parallel heating makes the downstream VDFs slightly anisotropic (T⊥/T‖ > 1) and possibly unstable to generation of proton cyclotron waves or mirror mode waves. Both wave modes have previously been observed in Venus's magnetosheath. The perpendicular heating is strongest in the near‐subsolar magnetosheath (T⊥/T‖≈3/2), which is also where mirror mode waves are most frequently observed. We believe that the mirror mode waves observed here are indeed generated by the anisotropy. In the magnetotail we observe planetary protons with largely isotropic VDFs, originating from Venus's ionosphere.

  • 4.
    Behar, Etienne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Solar Wind Dynamics within The Atmosphere of comet 67P/Churyumov-Gerasimenko2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, we explore the dynamics of the solar wind as it perme-ates and flows through a tenuous cometary atmosphere, with a focuson the interaction observed at comet 67P/Churyumov–Gerasimenko.

    Seven comets had already been visited by nine different probes when the European spacecraft Rosetta reached comet Churyumov–Gerasimenko in August 2014. The mission was however the first to orbit its host comet, which it did for a total duration of more than two years, corre-sponding to a large part of the comet’s orbit around the Sun. This en-abled to study how the dynamics of the plasma environment evolvedas the comet itself was transformed from one of the smallest obstaclesto the solar wind in the Solar System when far away from the Sun, toa well-established magnetosphere at perihelion.

    Most of our efforts tackle the early part of this transformation, when the creation of new-born cometary ions starts to induce significant disturbances to the incident flow. During this stage, a kinetic descrip-tion of the interaction is necessary, as the system of interest cannot be reduced to a hydrodynamic problem. This contrasts with the situation closer to the Sun, where a fluid treatment can be used, at Churyumov–Gerasimenko as well as at previously visited comets.

    Rosetta was not a mission dedicated to plasma studies, however. It directly translates into a limited spatial coverage of the cometary plasma environment, which by its nature extends over several spatial scales. An approach solely based on the analysis of in-situ data cannot properly address the major questions on the nature and physics of the plasma environment of Churyumov–Gerasimenko. This thesis there-fore largely exploits the experimental–analytical–numerical triad of approaches. In Chapters 3 and 4 we propose simple models of the ion dynamics and of the cometary plasma environment, and these are tested against experimental and numerical data. Used together,they give a global description of the solar wind ion dynamics through the cometary atmosphere, that we explore in the 2-dimensional and 3-dimensional cases (Chapter 5). In Chapter 6, we propose a view onthe interaction and its fluid aspects when closer to the Sun.

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  • 5.
    Behar, Etienne
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Nilsson, Hans
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Alho, M.
    Aalto University, School of Electrical Engineering, Department of Electronics and Nanoengineering, Finland.
    Goetz, C.
    Technische Universität Braunschweig, Institute for Geophysics and Extraterrestrial Physics, Germany.
    Tsurutani, B.
    Jet Propulsion Laboratory, California Institute of Technology, USA.
    The birth and growth of a solar wind cavity around a comet: Rosetta observations2017In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 469, no Suppl. 2, p. S369-S403Article in journal (Refereed)
    Abstract [en]

    The Rosetta mission provided detailed observations of the growth of a cavity in the solar wind around comet 67P/Churyumov–Gerasimenko. As the comet approached the Sun, the plasma of cometary origin grew enough in density and size to present an obstacle to the solar wind. Our results demonstrate how the initial slight perturbations of the solar wind prefigure the formation of a solar wind cavity, with a particular interest placed on the discontinuity (solar wind cavity boundary) passing over the spacecraft. The slowing down and heating of the solar wind can be followed and understood in terms of single particle motion. We propose a simple geometric illustration that accounts for the observations, and shows how a cometary magnetosphere is seeded from the gradual steepening of an initially slight solar wind perturbation. A perspective is given concerning the difference between the diamagnetic cavity and the solar wind cavity.

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  • 6.
    Behar, Etienne
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Nilsson, Hans
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Henri, P.
    LPC2E, CNRS, Orléans.
    Berecic, L.
    Swedish Institute of Space Physics, Kiruna.
    Nicolaou, G.
    Swedish Institute of Space Physics, Kiruna.
    Stenberg-Wieser, G.
    Swedish Institute of Space Physics, Kiruna.
    Wieser, M.
    Swedish Institute of Space Physics, Kiruna.
    Tabone, B.
    LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC Univ. Paris.
    Saillenfest, M.
    IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC Univ. Paris.
    Goetz, C.
    Technische Universität Braunschweig, Institute for Geophysics and Extraterrestrial Physics.
    The root of a comet tail: Rosetta ion observations at comet 67P/Churyumov–Gerasimenko2018In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 616, article id A21Article in journal (Refereed)
    Abstract [en]

    Context.The first 1000 km of the ion tail of comet 67P/Churyumov–Gerasimenko were explored by the EuropeanRosettaspacecraft,2.7 au away from the Sun.Aims.We characterised the dynamics of both the solar wind and the cometary ions on the night-side of the comet’s atmosphere.Methods.We analysed in situ ion and magnetic field measurements and compared the data to a semi-analytical model.Results.The cometary ions are observed flowing close to radially away from the nucleus during the entire excursion. The solar windis deflected by its interaction with the new-born cometary ions. Two concentric regions appear, an inner region dominated by theexpanding cometary ions and an outer region dominated by the solar wind particles.Conclusions.The single night-side excursion operated byRosettarevealed that the near radial flow of the cometary ions can beexplained by the combined action of three different electric field components, resulting from the ion motion, the electron pressuregradients, and the magnetic field draping. The observed solar wind deflection is governed mostly by the motional electric field−uion×B.

  • 7.
    Behar, Etienne
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Tabone, B.
    LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC Univ. Paris.
    Nilsson, Hans
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Dawn-dusk asymmetry induced by the Parker spiral angle in the plasma dynamics around comet 67P/Churyumov-Gerasimenko2018In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 478, no 2, p. 1570-1575Article in journal (Refereed)
    Abstract [en]

    When interacting, the solar wind and the ionised atmosphere of a comet exchange energy and momentum. Our aim is to understand the influence of the average Parker spiral configuration of the solar wind magnetic field on this interaction. We compare the theoretical expectations of an analytical generalised gyromotion with Rosetta observations at comet 67P/Churyumov-Gerasimenko. A statistical approach allows one to overcome the lack of upstream solar wind measurement. We find that additionally to their acceleration along (for cometary pick-up ions) or against (for solar wind ions) the upstream electric field orientation and sense, the cometary pick-up ions are drifting towards the dawn side of the coma, while the solar wind ions are drifting towards the dusk side of the coma, independent of the heliocentric distance. The dynamics of the interaction is not taking place in a plane, as often assumed in previous works.

  • 8.
    Behar, Etienne
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Tabone, B.
    LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC Univ. Paris.
    Saillenfest, M.
    IMCCE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC Univ. Paris.
    Henri, P.
    LPC2E, CNRS, Orléans.
    Deca, J.
    Laboratory for Atmospheric and Space Physics (LASP), University of Colorado Boulder.
    Lindkvist, J.
    Umeå University, Department of Physics.
    Holmström, Mats
    Swedish Institute of Space Physics, Kiruna.
    Nilsson, Hans
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Solar wind dynamics around a comet: A 2D semi-analytical kinetic model2018In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 620, article id A35Article in journal (Refereed)
    Abstract [en]

    Aims.We aim at analytically modelling the solar wind proton trajectories during their interaction with a partially ionised cometaryatmosphere, not in terms of bulk properties of the flow but in terms of single particle dynamics.Methods.We first derive a generalised gyromotion, in which the electric field is reduced to its motional component. Steady-stateis assumed, and simplified models of the cometary density and of the electron fluid are used to express the force experienced byindividual solar wind protons during the interaction.Results.A three-dimensional (3D) analytical expression of the gyration of two interacting plasma beams is obtained. Applying it to acomet case, the force on protons is always perpendicular to their velocity and has an amplitude proportional to 1/r2. The solar winddeflection is obtained at any point in space. The resulting picture presents a caustic of intersecting trajectories, and a circular regionis found that is completely free of particles. The particles do not lose any kinetic energy and this absence of deceleration, togetherwith the solar wind deflection pattern and the presence of a solar wind ion cavity, is in good agreement with the general results of theRosettamission.Conclusions.The qualitative match between the model and thein situdata highlights how dominant the motional electric field isthroughout most of the interaction region for the solar wind proton dynamics. The model provides a simple general kinetic descriptionof how momentum is transferred between these two collisionless plasmas. It also shows the potential of this semi-analytical modelfor a systematic quantitative comparison to the data.

  • 9.
    Berecic, Laura
    et al.
    Swedish Institute of Space Physics, Kiruna.
    Behar, Etienne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Nilsson, Hans
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna.
    Nicolaou, G.
    Swedish Institute of Space Physics, Kiruna.
    Stenberg-Wieser, G.
    Swedish Institute of Space Physics, Kiruna.
    Wieser, M.
    Swedish Institute of Space Physics, Kiruna.
    Goetz, C.
    Technische Universität Braunschweig, Institute for Geophysics and Extraterrestrial Physics.
    Cometary ion dynamics observed in the close vicinity of comet 67P/Churyumov-Gerasimenko during the intermediate activity period2018In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 613, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Aims.Cometary ions are constantly produced in the coma, and once produced they are accelerated and eventually escape the coma.We describe and interpret the dynamics of the cometary ion flow, of an intermediate active comet, very close to the nucleus and in theterminator plane.Methods.We analysed in situ ion and magnetic field measurements, and characterise the velocity distribution functions (mostly usingplasma moments). We propose a statistical approach over a period of one month.Results.On average, two populations were observed, separated in phase space. The motion of the first is governed by its interactionwith the solar wind farther upstream, while the second one is accelerated in the inner coma and displays characteristics compatiblewith an ambipolar electric field. Both populations display a consistent anti-sunward velocity component.Conclusions.Cometary ions born in different regions of the coma are seen close to the nucleus of comet 67P/Churyumov–Gerasimenko with distinct motions governed in one case by the solar wind electric field and in the other case by the position relative tothe nucleus. A consistent anti-sunward component is observed for all cometary ions. An asymmetry is found in the average cometaryion density in a solar wind electric field reference frame, with higher density in the negative (south) electric field hemisphere. Thereis no corresponding signature in the average magnetic field strengt

  • 10.
    Bergman, Sofia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Europa's Hydrogen Corona in a Large Set of HST Lyman-Alpha Images2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Far-ultraviolet (FUV) spectral images of Jupiter's moon Europa were obtained by the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) on 20 occasions between the years 1999 and 2015. In this thesis these data are analyzed to look for Lyman-alpha emissions from a hydrogen corona. This hydrogen corona was recently discovered in absorption, also from HST Lyman-alpha images but with Europa in transit of Jupiter, and the aim of this study is to confirm the existence of the corona also in emission. Europa's thin atmosphere is dominated by molecular oxygen, mainly produced by radiolysis and sputtering of the icy surface. Atomic hydrogen, the main target for this study, is produced by sputtering from the surface and the dissociation of H2 and H2O. It quickly escapes the gravity of Europa. To study the hydrogen corona in the spectral STIS images the data need to be processed to remove the other Lyman-alpha contributions to the image. These other contributions include emissions from the geocorona, emissions from the interplanetary medium (IPM), dark current in the detector and sunlight reflected from the surface of Europa. To estimate the contribution to the image from the hydrogen corona, a basic model of the expected emissions from the corona is developed. By fitting this model to the processed STIS data values of the hydrogen density and the surface Lyman-alpha albedo of the moon are obtained. The results confirm the presence of a hydrogen corona, with varying densities between the different observations but generally about twice as large as the results from the previous study. The uncertainty for the results is however large and there is a clear correlation between hydrogen density and background level in the image, for which the reason is poorly understood. No hemispheric variability or connections to the true anomaly of the moon are found, but the hydrogen density seems to be increasing during the time of the observations. The results for the albedo is consistent with previous results, indicating a lower albedo on the leading than on the trailing hemisphere.

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  • 11.
    Castro, Marley
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Felicetti, L.
    School of Aerospace Transport and Manufacturing, Cranfield University, Cranfield, MK43 0AL, United Kingdom.
    Sadeghi, Soheil
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Satpute, Sumeet
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Barabash, Victoria
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    de Oliveira, Élcio Jeronimo
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Westerberg, Lars-Göran
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Laufer, René
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Multi-Cubesat Mission For Auroral Acceleration Region Studies2021In: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, International Astronautical Federation (IAF) , 2021, article id 66544Conference paper (Refereed)
    Abstract [en]

    The Auroral Acceleration Region (AAR) is a key region in understanding the Magnetosphere-Ionosphere interaction. To understand the physical, spatial and temporal features of the region, multi-point measurements are required. Distributed small-satellite missions such as constellations of multiple nano satellites (for example multi-unit CubeSats) would enable such type of measurements. The capabilities of such a mission will highly depend on the number of satellites - one reason that makes low-cost platforms like CubeSats a very promising choice. In a previous study, the state-of-the-art of miniaturized payloads for AAR measurements was analyzed and evaluated and capabilities of different multi-CubeSat configurations equipped with such payloads in addressing different open questions in AAR were discussed. In this paper the mission analysis and possible mission design, as well as necessary technology developments of such multi-CubeSat mission are identified and presented.

  • 12.
    Castro, Marley Santiago
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Multiple CubeSat Mission for Auroral Acceleration Region Studies2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Auroral Acceleration Region (AAR) is a key region in understanding the interactionbetween the Magnetosphere and Ionosphere. To understand the physical, spatial, and temporal features of the region, multi-point measurements are required. Distributed small-satellite missions such as constellations of multiple nano satellites (for example multi-unit CubeSats) would enable such type of measurements. The capabilities of such a mission will highly depend on the number of satellites - one reason that makes low-cost platforms like CubeSats a very promising choice. In a previous study, the state-of-the-art of miniaturized payloads for AAR measurements was analyzed and evaluated on the capabilities of different multi-CubeSat configurations equipped with such payloads in addressing different open questions in AAR. This thesis will provide the mission analysis of such a multi-CubeSat mission to the AAR and possible mission design. This includes defining the mission scenario and associated requirements, developing a mathematical description of AAR that allows for specific regions in space to be targeted, an optimisation process for designing orbits targeting these regions, conversion of a satellite formation to appropriate orbits, verifying the scientific performance of this formation and the various costs associated with entering, maintaining, and exiting these orbits.

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  • 13.
    Chingaipe, Peter
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Simulation Study of Electrostatic Analyser Designs2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 14.
    Colmenares, Julian
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Ghazi, Diyar
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Plasma Burner: Numerical Modeling of Plasma Generation and Flow2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Technological evolution and mass production is impacting the Earth daily due to global warming caused by greenhouse gas emissions, where the biggest factor is the emission of carbon dioxide mostly caused by the burning of fossil fuel and industrial processes. Therefore, alternatives for substituting the use of fossil fuel in industries are extremely important. This thesis project investigates the method of using plasma technology using a plasma burner  which is electrically generated and could be an ideal solution for industrial metallurgical, chemical and mechanical processes due to its unique characteristics such as high energy densities, extremely high temperatures, rapid heating of surfaces and melting materials with a small installation size. Using the software COMSOL Multiphysics, a 2D model geometry is set up to simulate and investigate the behavior of the plasma burner by varying different parameters to improve the performance of the plasma burner. The results are based on simulations and no experiments were performed. However, we visited RISE ETC to observe and learn about the plasma burner model. At last, a geometry investigation was done by calculating the thermal efficiency to designate the most efficient geometry.

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  • 15.
    Delley, Diane
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Dengel, Ric
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Dierks, Björk
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Bravo, Elena Fernández
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Hartmann, Anne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Hiemstra, Cornelis Peter
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Janes, Noel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Lange, Jonathan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Maestro Redondo, Paloma
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Pérez Cámara, Flavia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Wolnievik, Andreas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Kuhn, Thomas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    ASTER: Developing a Platform to Achieve Microgravity for Low-Cost Experiments2021In: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, International Astronautical Federation, IAF , 2021, article id 66218Conference paper (Refereed)
    Abstract [en]

    Microgravity is an important field of research, which is vital for the efficient future utilisation of space. It is possible to undertake microgravity experiments on-orbit, however, this is often well outside the available funding range of low-cost experiments. Microgravity experiments undertaken on sounding rockets are more accessible to low-budget institutions and students, and provide longer periods of sustained microgravity than drop towers and parabolic flights. However, unless stabilised, such experiments cannot achieve true microgravity conditions due to residual external forces, such as the centrifugal force of the rocket’s spin, acting on the experiment. Thus, projects that want to carry out experiments in microgravity conditions would first need to design the platform required to achieve true microgravity, making these projects more complex and time intensive.

    Project ASTER (Attitude STabilised free falling ExpeRiment) is designing and testing such a platform for microgravity research. ASTER is taking advantage of the extended microgravity period of a sounding rocket flight to test a high performance, low-cost Attitude Control System (ACS) solution capable of providing microgravity conditions for experiments. This would greatly benefit both future satellite projects and sounding rocket experiments which require highly accurate stabilisation and pointing capabilities. The design utilises three reaction wheels controlled by a closed loop system to stabilise a Free Falling Unit - ejected from a sounding rocket - within seconds. The platform will be able to perform slewing manoeuvres and accommodate future experiments on easily adaptable mounting points which allow for on-board sensors and cameras. ASTER will be launched on-board REXUS 30 in March 2022, after which it will be recovered and the obtained results will be published on an open source basis to ensure its future availability to student and other low budget research projects, thereby allowing further improvement, optimisation, and customisation. ASTER is aiming to establish a platform which simplifies the development of microgravity experiments, especially for student projects which often face tight schedules and limited resources. ASTER is being developed as part of the 13th Cycle of the German-Swedish student programme REXUS/BEXUS by students of Luleå University of Technology (LTU) at the Kiruna Space Campus.

  • 16.
    Eritja Olivella, Antoni
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Real-Time Navigation for Swarms of Synthetic Aperture Radar (SAR) Satellites2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The pursuit of precision and flexibility in satellite missions has led to an increased number of formation flying missions being developed. These systems consist of multiple satellites flying at close distances (from a few kilometres to a few meters) to achieve common objectives. This master thesis delves into the domain of the Guidance, Navigation and Control (GNC) for formation flying satellite systems, aiming to propose a novel architecture of different sets of sensors capable of determining absolute and relative positioning of the formation, ensuring mission success. This research begins by providing an overall status of existing and tested in-space systems. It will be complemented with novel and other systems already tested and promising new technologies in development. The thesis then delves into the design of an absolute and a relative Extended Kalman Filter (EKF) for distributed Synthetic Aperture Radar (SAR) systems implemented as part of an in-house simulator. Concluding with the results when using simulated Global Navigation Satellite Systems (GNSS) data as the filter input. Finally, the thesis will be completed with a trade-off analysis of the sensor systems, which could be used in formation-flying satellite systems in the near future. The outcome of this thesis is a novel proposal of a set of sensors to be brought to space navigation, with a corresponding detailed trade-off analysis. Additionally, to validate some of the sensor systems, an EKF is proposed, implemented and tested with the results from an in-house formation flying simulator. This master thesis report is the outcome of the work done during an internship at the Microwave and Radar Institute of the Deutsche Zentrum für Luft- und Raumfahrt e.V. (DLR) – German Aerospace Center – in Oberpfaffenhofen, Bavaria, Germany.

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  • 17.
    Fetzer, Anton
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering. Aalto University.
    Radiation Shielding Simulations for Small Satellites on Geostationary Transfer Orbit2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The emergence of small and affordable satellites has led to rapid growth in the number of launched satellites over the past two decades. To save costs, small satellites often use mass-produced electronic components not explicitly designed for the radiation environment of space, which reduces reliability and makes them unsuitable for higher orbits. Improved radiation protection would enable small satellites to operate in high radiation environments and increase their reliability. This work investigates how small satellite electronics can be protected against the high radiation environment of geostationary transfer orbit on the example of the Foresail-2mission. Foresail-2 is a planned 6U CubeSat mission to the Earth radiation belts and is intended to use consumer-grade electronics components. In this harsh environment, most semiconductor devices require radiation shielding. The Space EnvironmentInformation System of the European Space Agency was used to analyse expected particle spectra along the planned orbit through the radiation belts. These particle spectra were then used in Monte-Carlo simulations based on the Geant4 particle transport toolkit to simulate the performance of different shielding configurations. Several thousand multilayer shielding configurations were simulated to optimise the material composition and layer structure of multilayer shielding. The best multilayer configurations against the combined proton and electron spectra of the Earth’s radiation belts use materials with low proton numbers on top of materials with high proton numbers and can significantly outperform conventional aluminium shielding. However, the usage of alternative materials might introduce significant overhead in the design and manufacturing of the satellite structure. Additionally, the influence of satellite structure geometry and openings in the shield was analysed. Even a 1 cm2 opening in the shield can increase the total ionising dose received by electronic components over a mission lifetime by more than an order of magnitude. In conclusion, the work recommends an aluminium body of 6 mm or equivalent multilayer shielding for the Foresail-2 mission to reduce the radiation level to a tolerable level for consumer-grade electronics, while openings in the satellite body should be avoided or covered up with additional shielding.

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  • 18.
    Giacomelli, Jasmine
    et al.
    Institute of Space Systems (IRS), University of Stuttgart, Pfaffenwaldring 29, Baden-Württemberg, Stuttgart, Germany.
    Herdrich, Georg
    Institute of Space Systems (IRS), University of Stuttgart, Pfaffenwaldring 29, Baden-Württemberg, Stuttgart, Germany.
    Oswald, Johannes
    Institute of Space Systems (IRS), University of Stuttgart, Pfaffenwaldring 29, Baden-Württemberg, Stuttgart, Germany.
    Pagan, Adam S.
    Institute of Space Systems (IRS), University of Stuttgart, Pfaffenwaldring 29, Baden-Württemberg, Stuttgart, Germany.
    Behnke, Alexander
    Institute of Space Systems (IRS), University of Stuttgart, Pfaffenwaldring 29, Baden-Württemberg, Stuttgart, Germany.
    Hyde, Truell
    Center of Astrophysics, Space Physics and Engineering Research (CASPER), Baylor University, 100 Research Pkwy, Waco, TX, United States.
    Laufer, Rene
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Experimental and numerical studies of MHD effects on plasma flows for re-entry applications2021In: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, International Astronautical Federation, IAF , 2021, article id 65321Conference paper (Refereed)
    Abstract [en]

    The design of safe heat flux control devices is fundamental for the success of a space mission that involves atmospheric re-entry. The development of the superconductive coil technology in recent years allows the exploitation of magnetohydrodynamics (MHD) effects as thermal protection system. Thus, experimental and numerical campaigns to assess these effects are needed, in order to provide a proven scientific base for future works in this field. Experiments involving a simplified test case with an argon plasma flow with different magnets configurations have been carried out in the plasma wind tunnel PWK1 at the Institute of Space Systems (IRS). The optical and emission spectroscopy measurements have shown that the magnetic field increases the emissions of the ionized argon particles and the shock stand-off distance. The test conditions have been emulated at the Center of Astrophysics, Space Physics and Engineering Research (CASPER) and a particle tracking technique was used to obtain an electric field force map. This experiment has shown that the electric field induced in the plasma by the applied magnetic field is strong enough to transport the ions towards to cusp region, in accordance with the highest emission intensity detected at IRS. The test case has been rebuilt with the IRS in-house code Self and Applied Field MPD thruster algorithm (SAMSA) and the numerical results have been validated against the experimental results. Further simulations with highest magnetic flux densities have been performed and a polynomial describing the behaviour of the shock distance has been obtained.

  • 19.
    Grethen-Bußmann, Antonia
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Thuswaldner, Malin
    Department of Mechanical Analysis, RUAG Space AB, ASJ-vägen 9, Linköping, 582 54, Sweden.
    Håkansson, Leif
    Department of Mechanical Analysis, RUAG Space AB, ASJ-vägen 9, Linköping, 582 54, Sweden.
    Andreasson, Magnus
    MSC Software Sweden AB, Hängpilsgatan 6, Gothenburg, 42677, Sweden.
    Laufer, René
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Comparative Study of Non-linear Analysis Tools for Release Simulations of Clampband-joint Separation Systems2021In: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates, International Astronautical Federation, IAF , 2021, article id 65712Conference paper (Refereed)
    Abstract [en]

    Reliable payload separation systems are of fundamental importance in any satellite mission. Due to the unique requirements of satellite missions, separation adapters must be modified for every novel spacecraft. Efficient and reliable analysis is needed to minimize the demand for qualification testing. The goal of this paper is to compare different modelling tools in order to develop a verified analysis approach to simulate spacecraft release using separation systems. This is achieved by validating the analysis results using data of a high-speed imaging test. A system by RUAG Space AB is used as a representation of a separation system, incorporating a clampband based connection and a Clampband Opening Device (CBOD) as a release actuator. The two commonly used programs MSC Nastran and Abaqus will be investigated as nonlinear Finite Element analysis methods. To evaluate the performance of the programs simulation time and the result deviations compared to the test results are being taken into account as parameters. With respect to the result deviations both programs have shown similar results, however neither program was able to achieve the desired accuracy. Regarding the simulation time Abaqus attained favourable results over MSC Nastran for the overall simulation.

  • 20.
    Gupta, Shashikant
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Cometary ion dynamics with Rosetta Ion Composition Analyzer2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    For centuries, comet sightings have fascinated us and we have strived to understand their nature. The knowledge of the behavior and composition of comets would help in understanding the formation of the Solar System, as they are believed to be the oldest objects in it. Cometary research, however, is in a developing stage because from an estimated trillion of comets, we have studied one through extended in-situ in-orbit measurements. Previous research has now established that comets become visible when they approach close to the Sun while their surface volatile material is sublimed by the solar radiation. The neutral atmosphere thus created is also ionized by the solar radiation, resulting in creation of positive cometary ions that are picked up and accelerated by the solar wind electric and magnetic fields. The fields influence the trajectories of these accelerated ions, causing variations in their flow angles as a function of their energy, a mechanism called energy - angle dispersion. Dispersion has only been studied for specific cases so far.

    In this work, the nature of the energy - angle dispersion is statistically examined using scientific data from the Rosetta mission, which orbited the Comet 67P/Churyumov-Gerasimenko from August 2014 to September 2016. One of the instruments onboard Rosetta, the Ion Composition Analyzer (ICA), measured the three-dimensional 360◦ × 90◦ energy and mass distribution of positive ions around the comet. In this work, the ICA data is used to identify dispersion events, their properties and trends using data analysis and image processing techniques at different temporal resolutions. The results are analyzed against the data from physical simulations, models and instruments onboard Rosetta. With the detailed statistical and quantitative analysis of the evolution of the energy - angle dispersion, it is found that the dispersion events are quite coherent over time scales of a few days and that the dispersion is very dynamic in nature. An understanding of this dispersion of accelerated cometary ions is key to understand the cometary ion dynamics.

  • 21.
    Hansson, Johan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    The 11-Year Magnetic Solar Cycle: Chaos Control Due to Jupiter2022In: Solar system research, ISSN 0038-0946, E-ISSN 1608-3423, Vol. 56, no 3, p. 191-194Article in journal (Refereed)
    Abstract [en]

    The observed magnetic field of the Sun is believed to originate from a “dynamo-effect” in its convective surface layer. However, there is no natural 11-year timescale in such models. We show that this timescale in the mean naturally and automatically arise through magnetic “chaos-control” of the inherently chaotic solar dynamo, mainly due to Jupiter, while also conforming to real and observed sunspot characteristics.

  • 22.
    Hettrich, Sebastian
    et al.
    German Federal Office for Radiation Protection, Oberschleißheim, Germany; Meteorological Institute, Ludwig Maximilian University, Munich, Germany.
    Kempf, Yann
    Finnish Meteorological Institute, Helsinki, Finland; University of Helsinki, Helsinki, Finland.
    Perakis, Nikolaos
    Department of Aerospace Engineering, Technical University of Munich, Munich, Germany.
    Górski, Jędrzej
    Wroclaw University of Technology, Wroclaw, Poland.
    Edl, Martina
    Karl-Franzens University, Graz, Austria.
    Urbář, Jaroslav
    Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic; Institute of Atmospheric Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
    Dósa, Melinda
    Space Research Group, Eötvös Loránd University, Budapest, Hungary.
    Gini, Francesco
    CISAS, University of Padova, Padova, Italy.
    Roberts, Owen W.
    Department of Mathematics and Physics, Aberystwyth University, Aberystwyth, United Kingdom.
    Schindler, Stefan
    Vienna University of Technology, Vienna, Austria.
    Schemmer, Maximilian
    École Normale Supérieure de Lyon, Lyon, France.
    Steenari, David
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Joldzić, Nina
    Vienna University of Technology, Vienna, Austria.
    Glesnes Ødegaard, Linn-Kristine
    Birkeland Centre for Space Science, Bergen, Norway; Department of Physics and Technology, University of Bergen, Bergen, Norway.
    Sarria, David
    IRAP, UPS-OMP CNRS, Toulouse, France.
    Volwerk, Martin
    Space Research Institute, Austrian Academy of Sciences, Graz, Austria.
    Praks, Jaan
    Aalto University, Espoo, Finland.
    Atmospheric drag, occultation 'N' ionospheric scintillation (ADONIS) mission proposal: Alpbach Summer School 2013 team orange2015In: Journal of Space Weather and Space Climate, E-ISSN 2115-7251, Vol. 5, article id A2Article in journal (Refereed)
    Abstract [en]

    The Atmospheric Drag, Occultation ‘N’ Ionospheric Scintillation mission (ADONIS) studies the dynamics of the terrestrial thermosphere and ionosphere in dependency of solar events over a full solar cycle in Low Earth Orbit (LEO). The objectives are to investigate satellite drag with in-situ measurements and the ionospheric electron density profiles with radio occultation and scintillation measurements. A constellation of two satellites provides the possibility to gain near real-time data (NRT) about ionospheric conditions over the Arctic region where current coverage is insufficient. The mission shall also provide global high-resolution data to improve assimilative ionospheric models. The low-cost constellation can be launched using a single Vega rocket and most of the instruments are already space-proven allowing for rapid development and good reliability. From July 16 to 25, 2013, the Alpbach Summer School 2013 was organised by the Austrian Research Promotion Agency (FFG), the European Space Agency (ESA), the International Space Science Institute (ISSI) and the association of Austrian space industries Austrospace in Alpbach, Austria. During the workshop, four teams of 15 students each independently developed four different space mission proposals on the topic of "Space Weather: Science, Missions and Systems", supported by a team of tutors. The present work is based on the mission proposal that resulted from one of these teams’ efforts.

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  • 23.
    Håkansson, Marcus
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Back-tracing of water ions at comet 67P/Churyumov–Gerasimenko2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper examines the neutral coma of comet 67P/Churyumov–Gerasimenko by using measurements of charged particles (water ions) and tracing them back to their place of ionisation. The measurements were taken from Rosetta’s Ion Composition Analyser. The simulations made use of an existing program which traces particles forward, which was changed to trace particles backwards, with new conditions for terminating the simulation.

    Two types of simulations were made. The first type is referred to as ”one-day simulations”. In these, simulations are made using data from a single occasion, with nine occasions studied per selected day. The days were selected so that the spacecraft was in different positions in relation to the comet. The second is referred to as the ”full-hemisphere” simulation. In this simulation, data from all usable days are used to produce an image of the hemisphere facing the Sun.

    The full-hemisphere simulation suffers from lack of simultaneous measurements, and indeed it is impossible to obtain in-situ measurements at all positions at once. Both simulations could be improved using more precise models, which could not be done within the allotted time of this work.

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  • 24.
    Jones, Geraint H.
    et al.
    Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, UK; The Centre for Planetary Sciences at UCL/Birkbeck, London, UK.
    Snodgrass, Colin
    The University of Edinburgh, Edinburgh, UK.
    Tubiana, Cecilia
    INAF, IAPS, Rome, Italy.
    Küppers, Michael
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Madrid, Spain.
    Kawakita, Hideyo
    Koyama Astronomical Observatory, Kyoto Sangyo University, Kyoto, Japan.
    Lara, Luisa M.
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Agarwal, Jessica
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    André, Nicolas
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Attree, Nicholas
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Auster, Uli
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Bagnulo, Stefano
    Armagh Observatory and Planetarium, Armagh, UK.
    Bannister, Michele
    University of Canterbury, Christchurch, New Zealand.
    Beth, Arnaud
    Department of Physics, Imperial College London, London, UK.
    Bowles, Neil
    Department of Physics, University of Oxford, Oxford, UK.
    Coates, Andrew
    Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, UK; The Centre for Planetary Sciences at UCL/Birkbeck, London, UK.
    Colangeli, Luigi
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Corral van Damme, Carlos
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Da Deppo, Vania
    CNR-Institute for Photonics and Nanotechnologies, Padova, Italy.
    De Keyser, Johan
    Royal Belgian Institute of Space Aeronomy, Brussels, Belgium.
    Della Corte, Vincenzo
    INAF, IAPS, Rome, Italy.
    Edberg, Niklas
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    El-Maarry, Mohamed Ramy
    Space and Planetary Science Center and Department of Earth Sciences, Khalifa University, Abu Dhabi, United Arab Emirates.
    Faggi, Sara
    NASA Goddard Space Flight Center, Greenbelt, USA.
    Fulle, Marco
    INAF – Osservatorio Astronomico di Trieste, Trieste, Italy.
    Funase, Ryu
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Galand, Marina
    Department of Physics, Imperial College London, London, UK.
    Goetz, Charlotte
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Groussin, Olivier
    Laboratoire d’Astrophysique de Marseille, Aix-Marseille Université, CNRS, Marseille, France.
    Guilbert-Lepoutre, Aurélie
    LGL-TPE, CNRS, ENS, Université Lyon1, UJM, Lyon, France.
    Henri, Pierre
    Laboratoire Lagrange, CNRS, OCA, Université Côte d’Azur, and LPC2E, CNRS, Université d’Orléans, CNES, Orléans, France.
    Kasahara, Satoshi
    The University of Tokyo, Tokyo, Japan.
    Kereszturi, Akos
    Konkoly Astronomical Institute, Research Centre for Astronomy and Earth Sciences, HUN-REN, Budapest, Hungary.
    Kidger, Mark
    European Space Agency (ESA), European Space Astronomy Centre (ESAC), Madrid, Spain.
    Knight, Matthew
    U.S. Naval Academy, Annapolis, USA.
    Kokotanekova, Rosita
    Institute of Astronomy and National Astronomical Observatory, Bulgarian Academy of Sciences, Sofia, Bulgaria.
    Kolmasova, Ivana
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Kossacki, Konrad
    Faculty of Physics, University of Warsaw, Warsaw, Poland.
    Kührt, Ekkehard
    DLR, Institute of Optical Sensor Systems, Berlin, Germany.
    Kwon, Yuna
    Caltech/IPAC, 1200 E California Blvd, MC 100-22, Pasadena, CA 91125, USA.
    La Forgia, Fiorangela
    Department of Physics and Astronomy, University of Padova, Padova, Italy.
    Levasseur-Regourd, Anny-Chantal
    LATMOS, Sorbonne Université, CNRS, CNES, Paris, France.
    Lippi, Manuela
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Longobardo, Andrea
    INAF, IAPS, Rome, Italy.
    Marschall, Raphael
    CNRS, Laboratoire J.-L. Lagrange, Observatoire de la Côte d’Azur, Nice, France.
    Morawski, Marek
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Muñoz, Olga
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Näsilä, Antti
    VTT Technical Research Centre of Finland Ltd, Espoo, Finland.
    Nilsson, Hans
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Opitom, Cyrielle
    The University of Edinburgh, Edinburgh, UK.
    Pajusalu, Mihkel
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Pommerol, Antoine
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Prech, Lubomir
    Charles University, Prague, Czech Republic.
    Rando, Nicola
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Ratti, Francesco
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Rothkaehl, Hanna
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Rotundi, Alessandra
    Dipartimento di Scienze e Tecnologie, Università degli Studi di Napoli “Parthenope”, Napoli, Italy.
    Rubin, Martin
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Sakatani, Naoya
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Sánchez, Joan Pau
    Institut Supérieur de l’Aéronautique et de l’Espace, Toulouse, France.
    Simon Wedlund, Cyril
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Stankov, Anamarija
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Thomas, Nicolas
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Toth, Imre
    Konkoly Astronomical Institute, Research Centre for Astronomy and Earth Sciences, HUN-REN, Budapest, Hungary.
    Villanueva, Geronimo
    NASA Goddard Space Flight Center, Greenbelt, USA.
    Vincent, Jean-Baptiste
    DLR Institute of Planetary Research, Berlin, Germany.
    Volwerk, Martin
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Wurz, Peter
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Wielders, Arno
    European Space Agency, ESTEC, Noordwijk, The Netherlands.
    Yoshioka, Kazuo
    The University of Tokyo, Tokyo, Japan.
    Aleksiejuk, Konrad
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Alvarez, Fernando
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Amoros, Carine
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Aslam, Shahid
    NASA Goddard Space Flight Center, Greenbelt, USA.
    Atamaniuk, Barbara
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Baran, Jędrzej
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Barciński, Tomasz
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Beck, Thomas
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Behnke, Thomas
    DLR Institute of Planetary Research, Berlin, Germany.
    Berglund, Martin
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Bertini, Ivano
    Dipartimento di Scienze e Tecnologie, Università degli Studi di Napoli “Parthenope”, Napoli, Italy.
    Bieda, Marcin
    Creotech Instruments, Piaseczno, Poland.
    Binczyk, Piotr
    Creotech Instruments, Piaseczno, Poland.
    Busch, Martin-Diego
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Cacovean, Andrei
    DLR Institute of Planetary Research, Berlin, Germany.
    Capria, Maria Teresa
    INAF, IAPS, Rome, Italy.
    Carr, Chris
    Department of Physics, Imperial College London, London, UK.
    Castro Marín, José María
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Ceriotti, Matteo
    University of Glasgow, Glasgow, UK.
    Chioetto, Paolo
    CNR-Institute for Photonics and Nanotechnologies, Padova, Italy.
    Chuchra-Konrad, Agata
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Cocola, Lorenzo
    CNR-Institute for Photonics and Nanotechnologies, Padova, Italy.
    Colin, Fabrice
    LPC2E, CNRS, Université d’Orléans, CNES, Orléans, France.
    Crews, Chiaki
    The Open University, Milton Keynes, UK.
    Cripps, Victoria
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Cupido, Emanuele
    Department of Physics, Imperial College London, London, UK.
    Dassatti, Alberto
    REDS, School of Management and Engineering Vaud, HES-SO University of Applied Sciences and Arts Western Switzerland, Delémont, Switzerland.
    Davidsson, Björn J. R.
    Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA.
    De Roche, Thierry
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Deca, Jan
    Laboratory for Atmospheric and Space Physics, University of Colorado Boulder, Boulder, USA.
    Del Togno, Simone
    DLR Institute of Planetary Research, Berlin, Germany.
    Dhooghe, Frederik
    Royal Belgian Institute of Space Aeronomy, Brussels, Belgium.
    Donaldson Hanna, Kerri
    Department of Physics, University of Central Florida, Orlando, USA.
    Eriksson, Anders
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Fedorov, Andrey
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Fernández-Valenzuela, Estela
    Florida Space Institute, University of Central Florida, Orlando, USA.
    Ferretti, Stefano
    Dipartimento di Scienze e Tecnologie, Università degli Studi di Napoli “Parthenope”, Napoli, Italy.
    Floriot, Johan
    Laboratoire d’Astrophysique de Marseille, Aix-Marseille Université, CNRS, Marseille, France.
    Frassetto, Fabio
    CNR-Institute for Photonics and Nanotechnologies, Padova, Italy.
    Fredriksson, Jesper
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Garnier, Philippe
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Gaweł, Dorota
    Creotech Instruments, Piaseczno, Poland.
    Génot, Vincent
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Gerber, Thomas
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Glassmeier, Karl-Heinz
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Granvik, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Physics, University of Helsinki, Helsinki, Finland.
    Grison, Benjamin
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Gunell, Herbert
    Umeå University, Umeå, Sweden.
    Hachemi, Tedjani
    LPC2E, CNRS, Université d’Orléans, CNES, Orléans, France.
    Hagen, Christian
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Hajra, Rajkumar
    Indian Institute of Technology Indore, Indore, India.
    Harada, Yuki
    Kyoto University, Kyoto, Japan.
    Hasiba, Johann
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Haslebacher, Nico
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Herranz De La Revilla, Miguel Luis
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Hestroffer, Daniel
    IMCCE, Paris Observatory, Université PSL, CNRS, Sorbonne Université, Univ. Lille, Paris, France.
    Hewagama, Tilak
    NASA Goddard Space Flight Center, Greenbelt, USA.
    Holt, Carrie
    Las Cumbres Observatory, Goleta, USA.
    Hviid, Stubbe
    DLR Institute of Planetary Research, Berlin, Germany.
    Iakubivskyi, Iaroslav
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Inno, Laura
    Dipartimento di Scienze e Tecnologie, Università degli Studi di Napoli “Parthenope”, Napoli, Italy.
    Irwin, Patrick
    Department of Physics, University of Oxford, Oxford, UK.
    Ivanovski, Stavro
    INAF – Osservatorio Astronomico di Trieste, Trieste, Italy.
    Jansky, Jiri
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Jernej, Irmgard
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Jeszenszky, Harald
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Jimenéz, Jaime
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Jorda, Laurent
    Laboratoire d’Astrophysique de Marseille, Aix-Marseille Université, CNRS, Marseille, France.
    Kama, Mihkel
    Tartu Observatory, University of Tartu, Tartu, Estonia; University College London, London, UK.
    Kameda, Shingo
    College of Science, Rikkyo University, Tokyo, Japan.
    Kelley, Michael S. P.
    Department of Astronomy, University of Maryland, College Park, USA.
    Klepacki, Kamil
    Creotech Instruments, Piaseczno, Poland.
    Kohout, Tomáš
    Department of Geosciences and Geography, University of Helsinki, Helsinki, Finland; Institute of Geology of the Czech Academy of Sciences, Prague, Czech Republic.
    Kojima, Hirotsugu
    Research Institute for Sustainable Humanosphere, Kyoto University, Kyoto, Japan.
    Kowalski, Tomasz
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Kuwabara, Masaki
    College of Science, Rikkyo University, Tokyo, Japan.
    Ladno, Michal
    Creotech Instruments, Piaseczno, Poland.
    Laky, Gunter
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Lammer, Helmut
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Lan, Radek
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Lavraud, Benoit
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, Nouvelle-Aquitaine, France.
    Lazzarin, Monica
    Department of Physics and Astronomy, University of Padova, Padova, Italy.
    Le Duff, Olivier
    LPC2E, CNRS, Université d’Orléans, CNES, Orléans, France.
    Lee, Qiu-Mei
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Lesniak, Cezary
    Creotech Instruments, Piaseczno, Poland.
    Lewis, Zoe
    Department of Physics, Imperial College London, London, UK.
    Lin, Zhong-Yi
    Institute of Astronomy, National Central University, Taoyuan, Taiwan.
    Lister, Tim
    Las Cumbres Observatory, Goleta, USA.
    Lowry, Stephen
    University of Kent, Kent, UK.
    Magnes, Werner
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Markkanen, Johannes
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Martinez Navajas, Ignacio
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Martins, Zita
    Centro de Química Estrutural, Institute of Molecular Sciences and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
    Matsuoka, Ayako
    Kyoto University, Kyoto, Japan.
    Matyjasiak, Barbara
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Mazelle, Christian
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Mazzotta Epifani, Elena
    INAF – Osservatorio Astronomico di Roma, Rome, Italy.
    Meier, Mirko
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Michaelis, Harald
    DLR Institute of Planetary Research, Berlin, Germany.
    Micheli, Marco
    ESA NEO Coordination Centre, Frascati, Italy.
    Migliorini, Alessandra
    INAF, IAPS, Rome, Italy.
    Millet, Aude-Lyse
    LPC2E, CNRS, Université d’Orléans, CNES, Orléans, France.
    Moreno, Fernando
    Instituto de Astrofisica de Andalucía – CSIC, Granada, Spain.
    Mottola, Stefano
    DLR Institute of Planetary Research, Berlin, Germany.
    Moutounaick, Bruno
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Muinonen, Karri
    Department of Physics, University of Helsinki, Helsinki, Finland.
    Müller, Daniel R.
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Murakami, Go
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Murata, Naofumi
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Myszka, Kamil
    Creotech Instruments, Piaseczno, Poland.
    Nakajima, Shintaro
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Nemeth, Zoltan
    Wigner Research Centre for Physics, Budapest, Hungary.
    Nikolajev, Artiom
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Nordera, Simone
    CNR-Institute for Photonics and Nanotechnologies, Padova, Italy.
    Ohlsson, Dan
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Olesk, Aire
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Ottacher, Harald
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Ozaki, Naoya
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Oziol, Christophe
    IRAP, CNRS, University Toulouse 3, CNES, Toulouse, France.
    Patel, Manish
    The Open University, Milton Keynes, UK.
    Savio Paul, Aditya
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Penttilä, Antti
    Department of Physics, University of Helsinki, Helsinki, Finland.
    Pernechele, Claudio
    INAF-Osservatorio Astronomico di Padova, Padova, Italy.
    Peterson, Joakim
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Petraglio, Enrico
    REDS, School of Management and Engineering Vaud, HES-SO University of Applied Sciences and Arts Western Switzerland, Delémont, Switzerland.
    Piccirillo, Alice Maria
    Dipartimento di Scienze e Tecnologie, Università degli Studi di Napoli “Parthenope”, Napoli, Italy.
    Plaschke, Ferdinand
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Polak, Szymon
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Postberg, Frank
    Freie Universitaet Berlin, Berlin, Germany.
    Proosa, Herman
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Protopapa, Silvia
    Southwest Research Institute, Boulder, USA.
    Puccio, Walter
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Ranvier, Sylvain
    Royal Belgian Institute of Space Aeronomy, Brussels, Belgium.
    Raymond, Sean
    Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, Nouvelle-Aquitaine, France.
    Richter, Ingo
    Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany.
    Rieder, Martin
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Rigamonti, Roberto
    REDS, School of Management and Engineering Vaud, HES-SO University of Applied Sciences and Arts Western Switzerland, Delémont, Switzerland.
    Ruiz Rodriguez, Irene
    Department of Physics, Imperial College London, London, UK.
    Santolik, Ondrej
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Sasaki, Takahiro
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Schrödter, Rolf
    DLR Institute of Planetary Research, Berlin, Germany.
    Shirley, Katherine
    Department of Physics, University of Oxford, Oxford, UK.
    Slavinskis, Andris
    Tartu Observatory, University of Tartu, Tartu, Estonia.
    Sodor, Balint
    SGF Ltd., Egyed, Hungary.
    Soucek, Jan
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Stephenson, Peter
    Department of Physics, Imperial College London, London, UK.
    Stöckli, Linus
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Szewczyk, Paweł
    Space Research Centre of the Polish Academy of Sciences, Warsaw, Poland.
    Troznai, Gabor
    SGF Ltd., Egyed, Hungary.
    Uhlir, Ludek
    Institute of Atmospheric Physics of the Czech Academy of Sciences, Prague, Czech Republic.
    Usami, Naoto
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Valavanoglou, Aris
    Austrian Academy of Sciences, Space Research Institute, Graz, Austria.
    Vaverka, Jakub
    Charles University, Prague, Czech Republic.
    Wang, Wei
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Wang, Xiao-Dong
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Wattieaux, Gaëtan
    Laboratoire Plasma et Conversion d’Energie (LAPLACE), CNRS, Université de Toulouse 3, Toulouse, France.
    Wieser, Martin
    Swedish Institute of Space Physics, Uppsala/Kiruna, Sweden.
    Wolf, Sebastian
    Space Research and Planetary Sciences, Physics Institute, University of Bern, Bern, Switzerland.
    Yano, Hajime
    Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Japan.
    Yoshikawa, Ichiro
    The University of Tokyo, Tokyo, Japan.
    Zakharov, Vladimir
    LESIA, Observatoire de Paris, Université PSL, Sorbonne Université, Université Paris Cité, CNRS, Paris, France.
    Zawistowski, Tomasz
    Creotech Instruments, Piaseczno, Poland.
    Zuppella, Paola
    CNR-Institute for Photonics and Nanotechnologies, Padova, Italy.
    Rinaldi, Giovanna
    INAF, IAPS, Rome, Italy.
    Ji, Hantao
    Department of Astrophysical Sciences, Princeton University, Princeton, USA.
    The Comet Interceptor Mission2024In: Space Science Reviews, ISSN 0038-6308, E-ISSN 1572-9672, Vol. 220, no 1, article id 9Article in journal (Refereed)
    Abstract [en]

    Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA’s F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum Δ V capability of 600 ms − 1 . Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes – B1, provided by the Japanese space agency, JAXA, and B2 – that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission’s science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.

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  • 25.
    Larkin, Cormac J.K.
    et al.
    Zentrum für Astronomie der Universität Heidelberg, Astronomisches Rechen-Institut, Mönchhofstr.12-14, 69120 Heidelberg, Germany; Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany; Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany; Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, the Netherlands.
    Lundén, Ville
    Department of Electronics and Nanotechnology, School of Electrical Engineering, Aalto University, Maarintie 8, 02150 Espoo, Finland.
    Schulz, Leonard
    Institute of Geophysics and Extraterrestrial Physics, Technische Universität Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany.
    Baumgartner-Steinleitner, Markus
    Institute of Theoretical and Computational Physics, Graz University of Technology, 8010 Graz, Austria.
    Brekkum, Marianne
    University of South-Eastern Norway, Raveien 215, 3184 Borre, Norway.
    Cegla, Adam
    Institute of Geodesy and Geoinformatics, Wrocław University of Environmental and Life Sciences, Grunwaldzka 53, 50-375 Wrocław, Poland.
    Dazzi, Pietro
    Laboratoire de Physique et Chimie de l’Environnement et de l’Espace (LPC2E), CNRS, Université d’Orléans, Orléans, France; LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC, Université Paris Diderot, Sorbonne Paris Cité, Meudon, France.
    De Iuliis, Alessia
    Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy.
    Gesch, Jonas
    Institute of Optical Sensor Systems, Deutsches Zentrum für Luft- und Raumfahrt e.V., Rutherfordstr. 2, 12489 Berlin, Germany.
    Lennerstrand, Sofia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Nesbit-Östman, Sara
    Department of Physics, Umeå University, SE-901 87 Umeå, Sweden.
    Pires, Vasco D.C.
    DEMec, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias 400, 4200-465 Porto, Portugal.
    Palanca, Ines Terraza
    Facultat de Física i Química, Universitat de Barcelona, Carrer de Martí i Franquès, 1, 11, 08028 Barcelona, Spain.
    Teubenbacher, Daniel
    Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, 8042 Graz, Austria; Institute of Physics, University of Graz, Universitätsplatz 5, 8010 Graz, Austria.
    Enengl, Florine
    Department of Physics, University of Oslo, Problemveien 7, 0315 Oslo.
    Hallmann, Marcus
    German Aerospace Center (DLR), Institute of Space Systems, Robert-Hooke-Str. 7, 28359 Bremen, Germany.
    M5 — Mars Magnetospheric Multipoint Measurement Mission: A multi-spacecraft plasma physics mission to Mars2024In: Advances in Space Research, ISSN 0273-1177, E-ISSN 1879-1948, Vol. 73, no 6, p. 3235-3255Article in journal (Refereed)
    Abstract [en]

    Mars, lacking an intrinsic dynamo, is an ideal laboratory to comparatively study induced magnetospheres, which can be found in other terrestrial bodies as well as comets. Additionally, Mars is of particular interest to further exploration due to its loss of habitability by atmospheric escape and possible future human exploration. In this context, we propose the Mars Magnetospheric Multipoint Measurement Mission (M5), a multi-spacecraft mission to study the dynamics and energy transport of the Martian induced magnetosphere comprehensively. Particular focus is dedicated to the largely unexplored magnetotail region, where signatures of magnetic reconnection have been found. Furthermore, a reliable knowledge of the upstream solar wind conditions is needed to study the dynamics of the Martian magnetosphere, especially the different dayside boundary regions but also for energy transport phenomena like the current system and plasma waves. This will aid the study of atmospheric escape processes of planets with induced magnetospheres. In order to resolve the three-dimensional structures varying both in time and space, multi-point measurements are required. Thus, M5 is a five spacecraft mission, with one solar wind monitor orbiting Mars in a circular orbit at 5 Martian radii, and four smaller spacecraft in a tetrahedral configuration orbiting Mars in an elliptical orbit, spanning the far magnetotail up to 6 Mars radii with a periapsis just outside the Martian magnetosphere of 1.8 Mars radii. We not only present a detailed assessment of the scientific need for such a mission but also show the resulting mission and spacecraft design taking into account all aspects of the mission requirements and constraints such as mass, power, and link budgets. Additionally, different aspects of the mission programmatics like a possible mission timeline, cost estimates, or public outreach are shown. The common requirements for acceptance for an ESA mission are considered. The mission outlined in this paper was developed during the Alpbach Summer School 2022 on the topic of “Comparative Plasma Physics in the Universe”.

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  • 26.
    Lepage, Thea
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Development of a model for ionospheric instabilities in the equatorial region2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work is part of a bigger project on analyzing the ionospheric dynamics in the equatorial region using simulations. The main objective of this study is to determine and characterize the parameters needed to trigger instabilities and thus the formation of plasma bubbles. An ambition is to keep the calculations as complete as possible by not oversimplifying the process itself as a classic Rayleigh-Taylor instability and by introducing the more realistic Generalized Eccentric Dipole description of the magnetic field. In this way, we aspire to avoid the neglect of convoluted interactions in the ionospheric system as well as the distorted nature of the geomagnetic field. After an in-depth study of the existing literature and getting to know the data generated by IPIM, I derived the equations describing the relevant physical processes based on fundamental plasma physics. In a MATLAB environment, I proceeded to develop the necessary tools for a computation of the quantities needed in the equations to then assemble and interpret the results for a simple study case. The found growth rate values are high enough and thus the characteristic time for the occurrence of instabilities short enough for them to be the principal process in the examined time and altitude range. It has been verified that the computed growth rate is such that instabilities may occur with a higher probability in the Southern Hemisphere due to the elevated amplitudes and the time delay between the foot points. We managed to derive a complete description of the equatorial ionosphere without using unreasonable approximations and the simplicity of the chosen configuration did not hinder the successful computation of instability seeds. The preparations that I undertook during this internship are an important first step for the subsequent development of the ionospheric model.

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  • 27.
    Lidström, Viktor
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Mass Loading of Space Plasmas2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The solar wind interaction with an icy comet is studied through a model problem. A hybrid simulation is done of a box with evenly distributed water ions and protons, where initially the water ions are stationary, and protons move with the speed of the solar wind. The purpose of the thesis is to investigate the interaction between the two species through the convective electric field, and focus is on early acceleration of pick-up ions, and deflection of the solar wind. It is relevant to the cometary case, because it enables study of the physics of this interaction, without involving other mechanisms, such as bow shock, magnetic field pile-up and draping. The species are found to exchange kinetic energy similar to a damped oscillator, where the dampening is caused by kinetic energy being transferred to the magnetic field. At early times, i.e. times smaller than the gyration time for the water ions, the solar wind does not lose much speed when it is deflected. For comparable number densities, the solar wind can be deflected more than 90° at early times, and loses more speed, and water ions are picked up faster. The total kinetic energy of the system decreases when energy builds up in the magnetic field. The nature of the energy exchange is strongly dependent on the number density ratio between water ions and protons. A density instability with behaviour similar to a plasma beam instability forms as energy in the magnetic field increases, and limits the amount of time the simulation preserves total energy, for the particular hybrid solver used. There is a discussion on the structure of the density instability, and it is compared to cometary simulations.

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  • 28.
    Lindblom, Ville
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Heavy Ion Temperature Anisotropies in the Venus Plasma Environment2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In a plasma environment particles and plasma waves have complex interactions and can affect each other significantly. The velocity distribution functions (VDFs) can effectively be used to try and understand these interactions. This study uses VDFs to investigate heavy ion temperatures in the Venusian plasma environment. A Maxwellian fitting methodology previously used to obtain proton plasma parameters is used to obtain plasma parameters for heavy ions instead. Ion and magnetic-field data are gathered from the ion mass analyser IMA and the magnetometer MAG which were on board the European spacecraft Venus Express. The temperature anisotropies are analysed to see if they may affect the observed plasma waves around Venus. Spatial maps of the obtained plasma parameters are presented, and the average values are shown. The temperature ratio T/Tis calculated to look for anisotropies. Case studies were made to investigate how well the methodology worked with heavy ion data. The methodology is shown to work well in the magnetotail, where heavy ions are expected, and less well in the magnetosheath and solar wind, where heavy ions were not expected. No statistically significant anisotropies were found for the heavy ions in the Venusian plasma environment.

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  • 29.
    MacLennan, Eric
    et al.
    Department of Physics, University of Helsinki, PO Box 64, 00014, Finland.
    Marshall, Sean
    Arecibo Observatory, University of Central Florida, HC-3 Box 53995, Arecibo, PR 00612, USA.
    Granvik, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Physics, University of Helsinki, PO Box 64, 00014, Finland.
    Evidence of surface heterogeneity on active asteroid (3200) Phaethon2022In: Icarus, ISSN 0019-1035, E-ISSN 1090-2643, Vol. 388, article id 115226Article in journal (Refereed)
    Abstract [en]

    Thermal infrared emission and thermophysical modeling techniques are powerful tools in deciphering the surface properties of asteroids. The near-Earth asteroid (3200) Phaethon is an active asteroid with a very small perihelion distance and is likely the source of the Geminid meteor shower. Using a thermophysical model with a non-convex shape of Phaethon we interpret thermal infrared observations that span ten distinct sightings. The results yield an effective diameter of 5.4 ± 0.1 km and independent thermal inertia estimates for each sighting. We find that the thermal inertia varies across each of these sightings in a way that is stronger than the theoretical temperature-dependent expectation from radiative heat transfer within the regolith. Thus, we test whether the variation in thermal inertia can be explained by the presence of a regolith layer over bedrock, or by a spatially heterogeneous scenario. We find that a model in which Phaethon's hemispheres have distinctly different thermophysical properties can sufficiently explain the thermal inertias determined herein. In particular, we find that a boundary is located between latitudes -ˆ’30°ˆ˜ and +10° and a northern hemisphere that is dominated by coarse-grained regolith and/or a high coverage of porous boulders. We discuss the implications related to Phaethon'€™s activity, potential association with 2005 UD, and the upcoming DESTINY+ mission.

  • 30.
    Moultaka, J.
    et al.
    IRAP, Université de Toulouse, CNRS, CNES, UPS, Toulouse, France.
    Eckart, A.
    I Physikalisches Institut, Universität zu Köln, Köln, Germany. Max-Planck-Institut für Radioastronomie, Bonn, Germany .
    Tikare, Kiran
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Bajat, A.
    Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic .
    High-spectral resolution M-band observations of CO Rot-Vib absorption lines towards the Galactic center2019In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 626, article id A44Article in journal (Refereed)
    Abstract [en]

    Context. In the near- to mid-infrared wavelength domain, bright continuum sources in the central parsec of the Galactic center (GC) are subject to foreground absorption. These sources therefore represent ideal probes of the intervening material that is responsible for the absorption along the line of sight.

    Aims. Our aim is to shed light on the location and physics of the absorbing clouds. We try to find out which of the gaseous absorbing materials is intimately associated with the GC and which one is associated with clouds at a much larger distance.

    Methods. We used the capabilities of CRIRES spectrograph located at ESO Very Large Telescope in Chile to obtain absorption spectra of individual lines at a high spectral resolution of R = 50 000, that is, 5 km s−1. We observed the 12CO R(0), P(1), P(2), P(3), P(4), P(5), P(6), P(7) and P(9) transition lines, applied standard data reduction, and compared the results with literature data.

    Results. We present the results of CRIRES observations of 13 infrared sources located in the central parsec of the Galaxy. The data provide direct evidence for a complex structure of the interstellar medium along the line of sight and in the close environment of the central sources. In particular we find four cold foreground clouds at radial velocities vLSR of the order of −145, −85, −60, and −40 ± 15 km s−1 that show absorption in the lower transition lines from R(0) to P(2) and in all the observed spectra. We also find in all sources an absorption in velocity range of 50–60 km s−1, possibly associated with the so-called 50 km s−1 cloud and suggesting an extension of this cloud in front of the GC. Finally, we detect individual absorption lines that are probably associated with material much closer to the center and with the sources themselves, suggesting the presence of cold gas in the local region.

  • 31.
    Möslinger, Anja
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Particle Trajectory Simulations for SCIENA-N: Conversion surface design for an ENA sensor head2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis serves as a preliminary design study for the combination of a flight-proven ion optics system (SWIM) with a conversion surface to create a small energetic neutral atom (ENA) sensor. It is planned to use this sensor as ENA sensor for the DFP-SCIENA instrument on Comet Interceptor. Due to the nature of the Comet Interceptor mission (ESA F-class mission with a maximum launch mass of 1000 kg) the development time for a new sensor that meets the size and weight restrictions is limited. The proposed combination of SWIM with a conversion surface is based on a proven ion optics design and should result in a compact sensor design.

    The main goal of this thesis was to simulate different conversion surface designs and evaluate their compatibility with the SWIM instrument. During this process the different designs were optimised based on the intermediate simulation results. The simulation process was performed by using SIMION to calculate particle trajectories. 

    In the end, two different conversion surface designs yielded promising results. With both designs detailed simulations and data analysis were conducted to determine the different properties of the two designs. One of these designs was chosen to be further investigated for use on the Comet Interceptor mission.

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  • 32.
    Nicolaou, G.
    et al.
    Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Behar, Etienne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Nilsson, Hans
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Wieser, M.
    Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Yamauchi, M.
    Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Berčič, Laura
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Stenberg Wieser, G.
    Swedish Institute of Space Physics, SE-981 28 Kiruna, Sweden.
    Energy-angle dispersion of accelerated heavy ions at 67P/Churyumov-Gerasimenko: Implication in the mass-loading mechanism2017In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 469, p. S339-S345Article in journal (Refereed)
    Abstract [en]

    The Rosetta spacecraft studied the comet 67P/Churyumov-Gerasimenko for nearly two years. The Ion Composition Analyzer instrument on board Rosetta observed the positive ion distributions in the environment of the comet during the mission. A portion of the comet's neutral coma is expected to get ionized, depending on the comet's activity and position relative to the Sun, and the newly created ions are picked up and accelerated by the solar wind electric field, while the solar wind flow is deflected in the opposite direction. This interaction, known as the mass-loading mechanism, was previously studied by comparing the bulk flow direction of both the solar wind protons and the accelerated cometary ions with respect to the direction of the magnetic and the convective solar wind electric field. In this study, we show that energy-angle dispersion is occasionally observed. We report two types of dispersion: one where the observed motion is consistent with ions gyrating in the local magnetic field and another where the energy-angle dispersion is opposite to that expected from gyration in the local magnetic field. Given that the cometary ion gyro-radius in the undisturbed solar wind magnetic and electric field is expected to be too large to be detected in this way, our observations indicate that the local electric field might be significantly smaller than that of the undisturbed solar wind. We also discuss how the energy-angle dispersion, which is not consistent with gyration, may occur due to spatially inhomogeneous densities and electric fields.

  • 33.
    Patel, Akash
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Banerjee, Avijit
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Lindqvist, Björn
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Kanellakis, Christoforos
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Nikolakopoulos, George
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Design and Model Predictive Control of a Mars Coaxial Quadrotor2022In: 2022 IEEE Aerospace Conference (AERO), IEEE, 2022Conference paper (Refereed)
    Abstract [en]

    Mars has been a prime candidate for planetary explo-ration of the solar system because of the science discoveries that support chances of future habitation on this planet. The Mars exploration landers and rovers have laid the foundation of our understanding of the planet's atmosphere and terrain. However, the rovers have presented limitations in terms of their pace, travers ability, and exploration capabilities from the ground and thus, one of the main field of interest for future robotic mission to Mars is to enhance the autonomy of this exploration vehicles. Martian caves and lava tubes like terrains, which consists of uneven ground, poor visibility and confined space, makes it impossible for wheel based rovers to navigate through these areas. In order to address these limitations and advance the exploration capability in a Martian terrain, this article presents the design and control of a novel coaxial quadrotor Micro Aerial Vehicle (MAV). As it will be presented, the key contributions on the design and control architecture of the proposed Mars coaxial quadrotor, are introducing an alternative and more enhanced, from a control point of view concept, when compared in terms of autonomy to Ingenuity. Based on the presented design, the article will introduce the mathematical modelling and automatic control framework of the vehicle that will consist of a linearised model of a co-axial quadrotor and a corresponding Model Pre-dictive Controller (MPC) for the trajectory tracking. Among the many models, proposed for the aerial flight on Mars, a reliable control architecture lacks in the related state of the art. The MPC based closed loop responses of the proposed MAV will be verified in different conditions during the flight with additional disturbances, induced to replicate a real flight scenario. For the model validation purpose, the Mars coaxial quadrotor is sim-ulated inside a Martian environment with related atmospheric conditions in the Gazebo simulator, which will use the proposed MPC controller for following an a priory defined trajectory. In order to further validate the proposed control architecture and prove the efficacy of the suggested design, the introduced Mars coaxial quadrotor and the MPC scheme will be compared to a PID-type controller, similar to the Ingenuity helicopter's control architecture for the position and the heading.

  • 34.
    Raudonis, Matthias
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Characterization and fault tolerance analysis of the RISC-V ISA for space applications2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 35.
    Rönner, Johannes Samuel Erland
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Contribution to the Understanding of the Effects of Propagation through the Ionosphere of P-band SAR Data2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The BIOMASS mission from the European Space Agency (ESA) is designed to measurebiomass and carbon content in Earth’s forests. To account for phase changes caused byionospheric variations, a map-drift autofocus algorithm is developed, which utilises a phasescreen of the ionosphere to eliminate phase errors in the signal. In this development, a filteris employed to integrate and remove noise from the second-order derivative of the ionosphericphase screen. This thesis aims to analyse methods to implement this filter andcompare their efficiency.

    Two filters are constructed using two methods, a Least Mean Square (LMS) filter and aWiener filter. Further emphasis is placed on the Wiener filter, and the most optimal way tocalculate it is explored in detail. The aim is to produce a filter that can integrate, lower theimpact of noise as much as possible and be computationally efficient. An implementationwas made in Python using simulated data of an ionosphere.

    The conclusion is that the Wiener filter can yield improved results if a precise estimation ofthe autocorrelation function of the ionospheric phase screen can be determined, and thatlinear regression models might be a method to do so. There is also consideration taken tothe noise of the data, it is compensated for by utilising multiple data sources. Additionally,to enhance computational efficiency, a comparison of different solving methods for the linearsystem of equations that is the filter where made, showing a LU-decomposition method tobe efficient.

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  • 36.
    Schillings, Audrey
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics.
    How does O+ outflow vary with solar wind conditions?2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The entire solar system including Earth is enveloped in a region of space where the Sun’s magnetic field dominates, this region is called the heliosphere. Due to this position in the heliosphere, a strong coupling exists between the Sun and our planet. The Sun continuously ejects particles, the solar wind, which is composed mainly of protons, electrons as well as some helium and heavier elements. These high energetic particles then hit the Earth and are partly deflected by the Earth’s magnetosphere (the region around Earth governed by the geomagnetic field). Depending on the strength of the solar wind hitting our planet, the magnetosphere is disturbed and perturbations can be seen down to the lower atmosphere.

    The upper atmosphere is affected by short wave-length solar radiation that ionise the neutral atoms, this region is referred to as the ionosphere. In the ionosphere, some of the heavier ion populations, such as O+, are heated and accelerated through several processes and flow upward. In the polar regions (polar cap, cusp and plasma mantle) these mechanisms are particularly efficient and when the ions have enough energy to escape the Earth’s gravity, they move outward along open magnetic field lines. These outflowing ions may be lost into interplanetary space.

    Another aspect that influences O+ ions are disturbed magnetospheric conditions. They correlate with solar active periods, such as coronal holes or the development of solar active regions. From these regions, strong ejections emerge, called coronal mass ejections (CMEs). When these CMEs interact with Earth, they produce a compression of the magnetosphere as well as reconnection between the terrestrial magnetic field lines and the interplanetary magnetic field (IMF) lines, which very often leads to geomagnetic storms. The energy in the solar wind as well as the coupling to the magnetosphere increase during geomagnetic storms and therefore the energy input to the ionosphere. This in turn increases the O+ outflow. In addition, solar wind parameter variations such as the dynamic pressure or the IMF also influence the outflowing ions.

    Our observations are made with the Cluster mission, a constellation of 4 satellites flying around Earth in the key magnetospheric regions where we usually observe ion outflow. In this thesis, we estimated O+ outflow for different solar wind parameters (IMF, solar wind dynamic pressure) and extreme ultraviolet radiations (EUV) as well as for extreme geomagnetic storms. We found that O+ outflow increases exponentially with enhanced geomagnetic activity (Kp index) and about 2 orders of magnitude during extreme geomagnetic storms compared to quiet conditions. Furthermore, our investigations on solar wind parameters showed that O+ outflow increases for high dynamic pressure and southward IMF, as well as with EUV radiations. Finally, the fate of O+ ions from the plasma mantle were studied based on Cluster observations and simulations. These results confirm that ions observed in the plasma mantle have sufficient energy to be lost in the solar wind.

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  • 37.
    Schillings, Audrey
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Swedish Institute of Space Physics, Kiruna, Sweden.
    O+ outflow during geomagnetic storms observed by Cluster satellites2018Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The region of space dominated by the Sun's magnetic field is called the heliosphere. It envelops the entire solar system including Earth. Therefore, a strong coupling exists between the Sun and our planet. The Sun continuously ejects particles, the solar wind, and when these high energy particles hit Earth, the magnetosphere (the region around the Earth governed by the geomagnetic field) is affected. When the solar wind is enhanced this disturbs the magnetosphere and perturbations can be seen also in ground-based observations.

    The upper atmosphere is subjected to solar radiation that ionise the neutral atoms and molecules, this region is referred to as the ionosphere. In the ionosphere, some of the heavier ion populations, such as O+, are heated and accelerated through several processes and flow upward. In the polar regions these mechanisms are particularly efficient and when the ions have enough energy to escape the Earth's gravity, they move outward along open magnetic field lines and may be lost into interplanetary space. Ion outflow in general has already been well studied, however, ion outflow under extreme magnetospheric conditions has not been investigated in detail.

    Disturbed magnetospheric conditions correlate with solar active periods, such as coronal holes or the development of solar active regions. From these regions, strong ejections called coronal mass ejections (CMEs) emerge. When these extreme events interact with Earth, they produce a compression of the magnetosphere as well as reconnection between the terrestrial magnetic field lines and the interplanetary magnetic field (IMF) lines, which most of the time leads to geomagnetic storms. The amounts of incoming solar particles and energy increase during geomagnetic storms and we also observe an increase in the O+ outflow.

    Our observations are made with the Cluster mission, a constellation of 4 satellites flying around Earth in the key magnetospheric regions where ion outflow is usually observed. In this thesis, we estimate O+ outflow under disturbed magnetospheric conditions and for several extreme geomagnetic storms. We find that O+ outflow lost into the solar wind increases exponentially with enhanced geomagnetic activity (Kp index) and increases about 2 orders of magnitude during extreme geomagnetic storms.

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  • 38.
    Svensson, Martin
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Electron heating in collisionless shocks observed by the MMS spacecraft2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Shock waves are ubiquitous in space and astrophysics. Shocks transform directed particle flow energy into thermal energy. As the major part of space is a collisionless medium, shocks in space physics arises through wave-particle interactions with the magnetic field as the main contributor.The heating processes are scale dependent. The large scale processes governs the ion heating and is well described by magnetohydrodynamics. The small scale processes governs the electron heating lies within the field of kinetic plasma theory and is still today remained disputed. A step towards the answer for the small scale heating would be to measure the scale, in order to relate it to a known instability or other small scale processes.The multi-spacecraft NASA MMS spacecraft carries several high resolute particle and field instruments enabling almost instantaneous 3D particle measurements and accurate measurements of the magnetic field. Also the separation between the four MMS spacecraft is as small as < 8km for a certain mission phase. This allows for new approaches when determining the scale which for shocks has not been possible before when using data from previous multi-spacecraft missions with spacecraft separation much larger. The velocity of the shock is large compared to the spacecraft,thus the shock width cannot be directly measured by each spacecraft. Either a constant velocity has to be estimated or we could use gradients of a certain parameter between the spacecraft as the shock flows over them. The usage of gradients is only possible with MMS as all the spacecraft could for MMS be within the shock simultaneously. The change for a parameter within the shockis assumed to be linear between the spacecraft and measurements. It is also assumed that the gradient of the parameter maximizes in the shock normal direction. Using these assumptions two methods have been developed. They have the same working principles but are using two or four spacecraft for linear estimation at each measurement point. From the gradient and parametric data the shock ramp width could then be found. The parameter used in this thesis is the electron temperature. The methods using one, two and four spacecraft were tested using electron temperature data from different shock crossings. Two problems with the gradient methods were found from the results, giving false data for certain time spans. To avoid these problems, the scale of the electron temperature gradient was determined for roughly half the shock ramp. It was found using the two and four spacecraft methods that an assumption of constant velocity for the shock speed is an uncertain assumption. The shock speed varies over short time scales and in the shock crossings analysed the constant velocity estimations were generally overestimated. From the two and four spacecraft methods roughly half of the temperature rise in the shock ramp occurred over 10.8km or 12.4 lpe. This is almost a factor of two greater than previous scale estimates using Cluster data and a multi-spacecraft timing method for shock speed estimation.From the results it is concluded that the methods when using gradients between spacecraft has some restrictions. They can only be used for MMS data, requires quasi-perpendicular high Mach number and will give false results if the temperature is disturbed by interacting hot plasma clouds. However, even though we have these limitations for the tested gradient methods, they were found better and more reliable compared to previous methods for shock scaling.

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  • 39.
    Szabo, Peter
    et al.
    Department of Physics and Materials Science, University of Luxembourg, Luxembourg, Luxembourg.
    Góger, Szabolcs
    Research Ctr. for Natural Sciences, Institute of Materials and Environmental Chemistry, Hungarian Academy of Sciences, Budapest, Hungary.
    Gustafsson, Magnus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Formation of the BeH+ and BeD+ Molecules in Be+ + H/D Collisions Through Radiative Association2021In: Frontiers in Astronomy and Space Sciences, E-ISSN 2296-987X, Vol. 8, article id 704953Article in journal (Refereed)
    Abstract [en]

    Cross sections and rate coefficients for the formation of BeH+ and BeD+ molecules in Be+ + H/D collisions through radiative association are calculated using quantum mechanical perturbation theory and Breit-Wigner theory. The local thermodynamic equilibrium limit of the molecule formation is also studied, since the process is also relevant in environments with high-density and/or strong radiation fields. The obtained rate coefficients may facilitate the kinetic modelling of BeH+/BeD+ production in astrochemical environments as well as the corrosion chemistry of thermonuclear fusion reactors.

  • 40.
    Tsirvoulis, Georgios
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Granvik, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Physics, PO Box 64, 00014, University of Helsinki, Finland.
    Toliou, Athanasia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    SHINeS: Space and High-Irradiance Near-Sun Simulator2022In: Planetary and Space Science, ISSN 0032-0633, E-ISSN 1873-5088, Vol. 217, article id 105490Article in journal (Refereed)
    Abstract [en]

    We present SHINeS, a space simulator which can be used to replicate the thermal environment in the immediate neighborhood of the Sun down to a heliocentric distance r ∼ 0.06 au. The system consists of three main parts: the solar simulator which was designed and constructed in-house, a vacuum chamber, and the probing and recording equipment needed to monitor the experimental procedures. Our motivation for building this experimental system was to study the effect of intense solar radiation on the surfaces of asteroids when their perihelion distances become smaller than the semi-major axis of the orbit of Mercury. Comparisons between observational data and recent orbit and size-frequency models of the population of near-Earth asteroids suggest that asteroids are super-catastrophically destroyed when they approach the Sun. Whereas the current models are agnostic about the disruption mechanism, SHINeS was developed to study the mechanism or mechanisms responsible. The system can, however, be used for other applications that need to study the effects of high solar radiation on other natural or artificial objects.

  • 41.
    Vech, Dániel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology. Department of Space Physics and Space Technologies, Wigner Research Centre for Physics, Budapest, Hungary.
    Szego, K.
    Department of Space Physics and Space Technologies, Wigner Research Centre for Physics, Budapest, Hungary.
    Opitz, A.
    Department of Space Physics and Space Technologies, Wigner Research Centre for Physics, Budapest, Hungary; European Space Research and Technology Center, European Space Agency, Noordwijk, Netherlands.
    Kajdic, P.
    Instituto de Geofísica, Universidad Nacional Autõnoma de México, Mexico City, Mexico.
    Fraenz, M.
    Max-Planck-Institute for Solar System Research, Göttingen, Germany.
    Kallio, E.
    Department of Radio Science and Engineering, University of Aalto, Espoo, Finland.
    Alho, M.
    Department of Radio Science and Engineering, University of Aalto, Espoo, Finland.
    Space weather effects on the bow shock, the magnetic barrier, and the ion composition boundary at Venus2015In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 120, no 6, p. 4613-4627Article in journal (Refereed)
    Abstract [en]

    We present a statistical study on the interaction between interplanetary coronal mass ejections (ICMEs) and the induced magnetosphere of Venus when the peak magnetic field of the magnetic barrier was anomalously large (>65nT). Based on the entire available Venus Express data set from April 2006 to October 2014, we selected 42 events and analyzed the solar wind parameters, the position of the bow shock, the size and plasma properties of the magnetic barrier, and the position of the ion composition boundary (ICB). It was found that the investigated ICMEs can be characterized with interplanetary shocks and unusually large tangential magnetic fields with respect to the Venus-Sun line. In most of the cases the position of the bow shock was not affected by the ICME. In a few cases the interaction between magnetic clouds and the induced magnetosphere of Venus was observed. During these events the small magnetosonic Mach numbers inside magnetic clouds caused the bow shock to appear at anomalously large distances from the planet. The positions of the upper and lower boundaries of the magnetic barrier were not affected by the ICMEs. The position of the ICB on the nightside was found closer to the planet during ICME passages which is attributed to the increased solar wind dynamic pressure. Key Points Statistical study of the ICME-Venus interaction Analysis of solar wind and magnetic barrier conditions during ICME passages Decreased altitude of the nightside ionosphere during ICME passages

  • 42.
    Villegas Prados, David
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Analysis of Hall effect thrusters using Hybrid PIC simulations and coupling to EP plume2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the last 30 years, numerical models have been developed to properly analyze Hall eect thrusters (HET),leading to a bridge between analytical prediction/empirical intuition and experiments. For companies in thespace sector, these codes serve to much more than simply simulating the thruster, but it provides a fast, cheapand reliable tool for processes such as validation and verication procedures, as well as for technical developmentof the thruster. During the testing of the thruster, mostly measurements upstream from the thruster exhaustare obtained since the high density plasma inside the channel disturbs any measurement inside the channel. Thisresults in the company knowing about the output of the thruster performance, but having little knowledge aboutthe processes and behavior of the thruster itself. The purpose of this study is to help reduce the uncertainty,using existing software to eectively analyze and understand HETs. Because of the physical nature of theproblem, HET simulations follow a multi-scale approach where the thruster is divided into two regions: insidechannel/near-plume region and far-plume region. To study each zone dierent softwares are typically used.This thesis aims to nd a common ground between both software, coupling them and creating a line of analysisto follow when studying HETs.The present thesis will focus on the analysis of the famous SPT-100. The design of this work can be divided intotwo: an hybrid-PIC simulation with a software focusing on the inside channel and near-plume region, Hallis; andanother hybrid-PIC simulation regarding the plasma plume expansion performed with SPIS-EP. During thisproject both software were mastered. Hallis is investigated, emphasizing the empirical modelling of the electronanomalous transport inside the thruster and its consequences on the output results. A sensitivity analysis isperformed to obtain a good set of the empirical parameters that drive the overall performance of the thrusterand the plasma behavior. Once a good match persist between Hallis and nominal operating conditions, theoutput is used to construct the input injection distributions needed by the plasma expansion software (SPIS).Finally, the plasma plume is simulated and results are compared to in-house experimental data. In this way,one is able to control and understand the nal output directly from the behavior of the thruster. It is importantto mention that due to condentiality reasons, the testing data cannot be fully shown and sometimes only thetrend can be analyzed.As a results of the analysis, it is found that establishing the coupling between softwares is feasible, but Halliscode needs to include some characteristics to fully take advantage of its potential. It is determined that theion denition followed by Hallis is enough to perfectly dene the ion energy distribution as well as generalperformance parameters of the SPT-100 (thrust, ionization eciency, power...), but the poor electron modelgenerates some deviation in the results. SPIS simulations and comparison with testing data suggest that Hallisoutput is not enough to properly match the experimental measurements, especially regarding the ion angledistribution function. According to Hallis, such distribution is too narrow compared to the observed plasmaplume. This problem is found to be caused by the small simulation domain of Hallis. Hence, although couplingof the software is easy, more functionalities of Hallis would allow for a better study and more accurate results.

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  • 43.
    Viviano, Mirko
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Space Technology.
    Moon plasma environment and its implications for lunar space missions2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]
    • This study investigates the lunar plasma environment and its implications for the safety and success of future crewed missions to the Moon. The Moon’splasma environment, formed by the solar wind, galactic cosmic rays and solar flare particles, presents potential hazards to human life and property. The study focuses on simulating the lunar plasma environment at various points along the Moon’s orbit, particularly in regions behind the Earth, such as the bow shock, magnetotail, and magnetosheath, using a self-consistent 3D quasineutral hybrid model. The findings of this work reveal significant variations in plasma characteristics, such as density, temperature and velocity. This thesis identifies potential risks to human health, surface infrastructure and spacecraft systems due to these dynamic plasma conditions, especially in regions with increased plasma density and temperature. By analysing the simulation results, this research aims to enhance the understanding of the plasma environment’s effects on human resources and life, ultimately contributing to the safety and success of future crewed missions to the Moon.
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