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  • 1.
    Albers, Roland
    et al.
    Institute of Applied Physics, University of Bern, Bern, Switzerland.
    Andrews, Henrik
    Norwegian University of Science and Technology, Høgskoleringen 1, Trondheim, 7034, Norway.
    Boccacci, Gabriele
    Sapienza University of Rome, Rome, Italy.
    Pires, Vasco D.C.
    DEMec, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, Porto, 4200-465, Portugal; Chair of Designing Plastics and Composite Materials, Department of Polymer Engineering and Science, Montanuniversitaet Leoben, Otto Glöckel-Straße 2, Leoben, 8700, Austria.
    Laddha, Sunny
    Space Research Institute Graz, Austrian Academy of Sciences, Schmiedlstraße 6, Graz, 8042, Austria.
    Lundén, Ville
    Department of Electronics and Nanotechnology, School of Electrical Engineering, Aalto University, Maarintie 8, Espoo, 02150, Finland.
    Maraqten, Nadim
    University of Stuttgart, Pfaffenwaldring 29, Stuttgart, 70569, Germany.
    Matias, João
    Department of Aeronautics, Imperial College London, Exhibition Road, London, SW7 2AZ, United Kingdom.
    Krämer, Eva
    Department of Physics, Umeå University, Umeå, Sweden.
    Schulz, Leonard
    Institute of Geophysics and Extraterrestrial Physics, Technische Universität Braunschweig, Braunschweig, 38106, Germany.
    Palanca, Ines Terraza
    Faculty of Physics, University of Barcelona, Barcelona, 08028, Spain.
    Teubenbacher, Daniel
    Space Research Institute Graz, Austrian Academy of Sciences, Schmiedlstraße 6, Graz, 8042, Austria; Institute of Physics/IGAM, University of Graz, Graz, Austria.
    Baskevitch, Claire
    UMR8190 LATMOS (CNRS/Sorbonne Université), 4 place Jussieu, Paris, 75252, France; UMR8109, LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, Meudon, 92195, France.
    Covella, Francesca
    Imperial College, London, United Kingdom.
    Cressa, Luca
    Advanced Instrumentation for Nano-Analytics (AINA), Luxembourg Institute of Science and Technology, 41 Rue du Brill, Belvaux, 4422, Luxembourg.
    Moreno, Juan Garrido
    Universitat Politècnica de Catalunya - BarcelonaTech (UPC), 11 Colom St., Terrassa, 08222, Catalonia, Spain.
    Gillmayr, Jana
    University of Graz, Rechbauerstraße 12, Graz, 8010, Austria.
    Hollowood, Joshua
    Department of Earth and Environmental Sciences, The University of Manchester, Manchester, M13 9PL, United Kingdom.
    Huber, Kilian
    Faculty of Science, Technology and Medicine, University of Luxembourg, 2 Avenue de l’Université, Esch-sur-Alzette, 4365, Luxembourg; Advanced Instrumentation for Nano-Analytics (AINA), Luxembourg Institute of Science and Technology, 41 Rue du Brill, Belvaux, 4422, Luxembourg.
    Kutnohorsky, Viktoria
    Institute for Geophysics and Astrophysics, University of Graz, Graz, Austria.
    Lennerstrand, Sofia
    Luleå tekniska universitet.
    Malatinszky, Adel
    Space Research Laboratory, Centre for Energy Research, Konkoly-Thege Miklós út 29-33, Budapest, 1121, Hungary.
    Manzini, Davide
    Laboratoire de Physique des Plasmas (LPP), CNRS, École Polytechnique, Sorbonne Université, Université Paris-Saclay, Observatoire de Paris, Palaiseau, 91120, France; Dipartimento di Fisica “Enrico Fermi”, Università di Pisa, Pisa, 56127, Italy.
    Maurer, Manuel
    University of Graz, Universitätsplatz 3, Graz, 8010, Austria.
    Nidelea, Daiana Maria Alessandra
    Politehnica University of Bucharest, Bucharest, Romania.
    Rigon, Luca
    Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland.
    Sinjan, Jonas
    Max–Planck-Institut für Sonnensystemforschung, Justus-von-Liebig Weg 3, Göttingen, 37077, Germany.
    Suarez, Crisel
    Vanderbilt University, 12201 West End Ave, Nashville, 37235, TN, USA; The Center for Astrophysics, Harvard and Smithsonian, 60 Garden St, Cambridge, 02138, MA, USA.
    Viviano, Mirko
    Department of Electronics and Nanotechnology, School of Electrical Engineering, Aalto University, Maarintie 8, Espoo, 02150, Finland.
    Knutsen, Elise Wright
    LATMOS/IPSL, UVSQ Université Paris-Saclay, Sorbonne Universit, CNRS, Guyancourt, France.
    Magnetospheric Venus Space Explorers (MVSE) mission: A proposal for understanding the dynamics of induced magnetospheres2024Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 221, s. 194-205Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Induced magnetospheres form around planetary bodies with atmospheres through the interaction of the solar wind with their ionosphere. Induced magnetospheres are highly dependent on the solar wind conditions and have only been studied with single spacecraft missions in the past. Without simultaneous measurements of solar wind variations and phenomena in the magnetosphere, establishing a link between both can only be done indirectly, using statistics over a large set of measurements. This gap in knowledge could be addressed by a multi-spacecraft plasma mission, optimized for studying global spatial and temporal variations in the magnetospheric system around Venus, which hosts the most prominent example of an induced magnetosphere in our solar system. The MVSE mission comprises four satellites, of which three are identical scientific spacecraft, carrying the same suite of instruments probing different regions of the induced magnetosphere and the solar wind simultaneously. The fourth spacecraft is the transfer vehicle which acts as a relay satellite for communications at Venus. In this way, changes in the solar wind conditions and extreme solar events can be observed, and their effects can be quantified as they propagate through the Venusian induced magnetosphere. Additionally, energy transfer in the Venusian induced magnetosphere can be investigated. The scientific payload includes instrumentation to measure the magnetic field, electric field, and ion–electron velocity distributions. This study presents the scientific motivation for the mission as well as requirements and the resulting mission design. Concretely, a mission timeline along with a complete spacecraft design, including mass, power, communication, propulsion and thermal budgets are given. This mission was initially conceived at the Alpbach Summer School 2022 and refined during a week-long study at ESA's Concurrent Design Facility in Redu, Belgium.

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  • 2.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laboratory experiments with a laser-based attachment mechanism for small bodiesIngår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030Artikel i tidskrift (Refereegranskat)
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  • 3.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Laboratory experiments with a laser-based attachment mechanism for spacecraft at small bodies2021Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 189, s. 391-397Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 4.
    Anthony, Niklas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Frostevarg, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Suhonen, Heikki
    Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Wanhainen, Christina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland.
    Laser-induced spallation of minerals common on asteroids2021Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 182, s. 325-331Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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  • 5.
    Barabash, Victoria
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Milz, Mathias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Kuhn, Thomas
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Laufer, Rene
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Development of a competence ecosystem for the future space workforce: strategies, practices and recommendations from international master programs in northern Sweden2022Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 197, s. 46-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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  • 6.
    Bazzocchi, Michael C.F.
    et al.
    Institute for Aerospace Studies, University of Toronto.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Comparative analysis of redirection methods for asteroid resource exploitation2016Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 120, s. 1-19Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An in-depth analysis and systematic comparison of asteroid redirection methods is performed within a resource exploitation framework using different assessment mechanisms. Through this framework, mission objectives and constraints are specified for the redirection of an asteroid from a near-Earth orbit to a stable orbit in the Earth-Moon system. The paper provides a detailed investigation of five redirection methods, i.e., ion beam, tugboat, gravity tractor, laser sublimation, and mass ejector, with respect to their capabilities for a redirection mission. A set of mission level criteria are utilized to assess the performance of each redirection method, and the means of assigning attributes to each criterion is discussed in detail. In addition, the uncertainty in physical characteristics of the asteroid population is quantified through the use of Monte Carlo analysis. The Monte Carlo simulation provides insight into the performance robustness of the redirection methods with respect to the targeted asteroid range. Lastly, the attributes for each redirection method are aggregated using three different multicriteria assessment approaches, i.e., the analytical hierarchy process, a utility-based approach, and a fuzzy aggregation mechanism. The results of each assessment approach as well as recommendations for further studies are discussed in detail.

  • 7.
    Bazzocchi, Michael C.F.
    et al.
    Institute for Aerospace Studies, University of Toronto, Toronto, Ontario, Canada.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Stochastic optimization of asteroid three-dimensional trajectory transfer2018Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 152, s. 705-718Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work, an approach to designing near-optimal nonplanar transfer trajectories for asteroids is introduced, taking into account the uncertainty in asteroid parameters. The approach is demonstrated using a specific known Near-Earth Asteroid (NEA) as a model for the transfer scenario. The designed trajectory redirects the NEA from its current orbit about the Sun to a new orbit in the Earth-Moon system. The approach utilizes a low-thrust redirection method, namely the ion beam method, to execute the transfer; however, the work can be extrapolated to most low-thrust redirection methods. Asteroid parameters, such as absolute magnitude, albedo and density, are modelled, and a Monte Carlo analysis is employed to investigate the redirection maneuver in light of the expected variation in parameters. The trajectory transfer is modelled in three dimensions through the use of pseudo-equinoctial shaping, and is subsequently optimized. Due to the large design space created by the 21 decision variables, the optimization is parsed into two main steps; first, a global optimization that employs a genetic algorithm, followed by a local optimization that utilizes sequential quadratic programming to refine the result from the global optimization. Lastly, the results of the Monte Carlo analysis for the near-optimal trajectory transfer of the NEA are discussed.

  • 8.
    Conte, Davide
    et al.
    The Pennsylvania State University.
    Di Carlo, Marilena
    University of Strathclyde.
    Budzyń, Dorota
    ESA/EAC, Linder Höhe, Cologne.
    Burgoyne, Hayden
    Analytical Space, Inc., Boston.
    Fries, Dan
    Georgia Institute of Technology.
    Grulich, Maria
    ESA/ESTEC.
    Heizmann, Sören
    Universität Stuttgart.
    Jethani, Henna
    Blue Origin.
    Lapôtre, Mathieu
    California Institute of Technology.
    Roos, Tobias
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Castillo, Encarnación Serrano
    Università di Bologna.
    Scherrmann, Marcel
    ESA/ESTEC.
    Vieceli, Rhiannon
    New Mexico Institute of Mining and Technology.
    Wilson, Lee
    California Institute of Technology.
    Wynard, Christopher
    NASA Johnson Space Center.
    Advanced concept for a crewed mission to the martian moons2017Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 139, s. 545-563Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the conceptual design of the IMaGInE (Innovative Mars Global International Exploration) Mission. The mission's objectives are to deliver a crew of four astronauts to the surface of Deimos and perform a robotic exploration mission to Phobos. Over the course of the 343 day mission during the years 2031 and 2032, the crew will perform surface excursions, technology demonstrations, In Situ Resource Utilization (ISRU) of the Martian moons, as well as site reconnaissance for future human exploration of Mars. This mission design makes use of an innovative hybrid propulsion concept (chemical and electric) to deliver a relatively low-mass reusable crewed spacecraft (approximately 100 mt) to cis-martian space. The crew makes use of torpor which minimizes launch payload mass. Green technologies are proposed as a stepping stone towards minimum environmental impact space access. The usage of beamed energy to power a grid of decentralized science stations is introduced, allowing for large scale characterization of the Martian environment. The low-thrust outbound and inbound trajectories are computed through the use of a direct method and a multiple shooting algorithm that considers various thrust and coast sequences to arrive at the final body with zero relative velocity. It is shown that the entire mission is rooted within the current NASA technology roadmap, ongoing scientific investments and feasible with an extrapolated NASA Budget. The presented mission won the 2016 Revolutionary Aerospace Systems Concepts - Academic Linkage (RASC-AL) competition.

  • 9.
    Felicetti, Leonard
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    A multi-spacecraft formation approach to space debris surveillance2016Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 127, s. 491-504Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper proposes a new mission concept devoted to the identification and tracking of space debris through observations made by multiple spacecraft. Specifically, a formation of spacecraft has been designed taking into account the characteristics and requirements of the utilized optical sensors as well as the constraints imposed by sun illumination and visibility conditions. The debris observations are then shared among the team of spacecraft, and processed onboard of a “hosting leader” to estimate the debris motion by means of Kalman filtering techniques. The primary contribution of this paper resides on the application of a distributed coordination architecture, which provides an autonomous and robust ability to dynamically form spacecraft teams once the target has been detected, and to dynamically build a processing network for the orbit determination of space debris. The team performance, in terms of accuracy, readiness and number of the detected objects, is discussed through numerical simulations.

  • 10.
    Felicetti, Leonard
    et al.
    University of Rome La Sapienza, Italy.
    Gasbarri, Paolo
    University of Rome La Sapienza, Italy.
    Pisculli, Andrea
    University of Rome La Sapienza, Italy.
    Sabatini, Marco
    University of Rome La Sapienza, Italy.
    Palmerini, Giovanni B.
    University of Rome La Sapienza, Italy.
    Design of robotic manipulators for orbit removal of spent launchers' stages2016Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 119, s. 118-130Artikel i tidskrift (Refereegranskat)
  • 11.
    Felicetti, Leonard
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Palmerini, Giovanni B.
    Sapienza Università di Roma, Dipartimento di Ingegneria Astronautica Elettrica Ed Energetica (DIAEE), Scuola di Ingegneria Aerospaziale, Università di Roma La Sapienza.
    Analytical and numerical investigations on spacecraft formation control by using electrostatic forces2016Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 123, s. 455-469Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper investigates some analytical and numerical aspects of the formation control exploited by means of inter-spacecraft electrostatic actions. The analysis is based on the evaluation and check of the stability issues by using a sequence of purposely defined Lyapunov functions. The same Lyapunov approach can also define a specific under-actuate control strategy for controlling selected “virtual links” of the formation. Two different selection criteria for these links are then discussed, showing the implications on the control chain. An optimal charge distribution strategy, which assigns univocally the charges to all the spacecraft starting from the charge products computed by the control, is also presented and discussed. Numerical simulations prove the suitability of the proposed approach to a formation of 4 satellites.

  • 12.
    Gassot, Oriane
    et al.
    Univ. Grenoble Alpes, CNRS, IPAG, 38000, Grenoble, France.
    Panicucci, Paolo
    CNES, 18 Avenue Edouard Belin, 31400, Toulouse, France; ISAE-SUPAERO, 10 Avenue Edouard Belin, 31400, Toulouse, France; Airbus Defence & Space, 31 Rue des Cosmonautes, 31400, Toulouse, France.
    Acciarini, Giacomo
    University of Strathclyde, UK.
    Bates, Helena
    Natural History Museum, London, UK; University of Oxford, UK.
    Caballero, Manel
    Universitat Politècnica de Catalunya, Spain.
    Cambianica, Pamela
    INAF - Astronomical Observatory of Padova, Vicolo dell’Osservatorio 5, 35122, Padova, Italy.
    Dziewiecki, Maciej
    Wroclaw University of Science and Technology, Poland.
    Dionnet, Zelia
    Università degli Studi di Napoli Parthenope, Italy.
    Enengl, Florine
    KTH Royal Institute of Technology, Sweden.
    Gerig, Selina-Barbara
    Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012, Bern, Switzerland.
    Hessinger, Felix
    Luleå tekniska universitet.
    Kissick, Lucy
    University of Oxford, UK.
    Novak, Moritz
    Vienna University of Technology, Austria.
    Pellegrino, Carmine
    Techincal University of Munich, Institute for Nanoelectronics, 80333, Munich, Germany.
    Pontoni, Angèle
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Ribeiro, Tânia M.
    IFIMUP and Departamento de Física e Astronomia, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4169-007, Porto, Portugal.
    Riegler, Clemens
    JMU Würzburg, Germany.
    Berge, Nini
    Laboratoire de Physique et de Chimie de l’Environnement et de l’Espace, University of Orleans, CNRS, France.
    Huber, Nikolaus
    Uppsala University, Sweden.
    Hynek, Richard
    University of West Bohemia, Czech Republic.
    Kędziora, Bartosz
    Warsaw University of Technology, Poland.
    Kiss, Adam
    Budapest University of Technology and Economics, Hungary.
    Martin, Maurice
    University of Stuttgart, Germany.
    Navarro Montilla, Javier
    Institut National des Sciences Appliquées, France.
    Calathus: A sample-return mission to Ceres2021Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 181, s. 112-129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ceres, as revealed by NASA's Dawn spacecraft, is an ancient, crater-saturated body dominated by low-albedo clays. Yet, localised sites display a bright, carbonate mineralogy that may be as young as 2 Myr. The largest of these bright regions (faculae) are found in the 92 km Occator Crater, and would have formed by the eruption of alkaline brines from a subsurface reservoir of fluids. The internal structure and surface chemistry suggest that Ceres is an extant host for a number of the known prerequisites for terrestrial biota, and as such, represents an accessible insight into a potentially habitable “ocean world”. In this paper, the case and the means for a return mission to Ceres are outlined, presenting the Calathus mission to return to Earth a sample of the Occator Crater faculae for high-precision laboratory analyses. Calathus consists of an orbiter and a lander with an ascent module: the orbiter is equipped with a high-resolution camera, a thermal imager, and a radar; the lander contains a sampling arm, a camera, and an on-board gas chromatograph mass spectrometer; and the ascent module contains vessels for four cerean samples, collectively amounting to a maximum 40 g. Upon return to Earth, the samples would be characterised via high-precision analyses to understand the salt and organic composition of the Occator faculae, and from there to assess both the habitability and the evolution of a relict ocean world from the dawn of the Solar System.

  • 13.
    Hakima, Houman
    et al.
    University of Toronto Institute for Aerospace Studies, 4925 Dufferin Street, Toronto.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Institute for Aerospace Studies, University of Toronto.
    Assessment of active methods for removal of LEO debris2018Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 144, s. 225-243Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper investigates the applicability of five active methods for removal of large low Earth orbit debris. The removal methods, namely net, laser, electrodynamic tether, ion beam shepherd, and robotic arm, are selected based on a set of high-level space mission constraints. Mission level criteria are then utilized to assess the performance of each redirection method in light of the results obtained from a Monte Carlo simulation. The simulation provides an insight into the removal time, performance robustness, and propellant mass criteria for the targeted debris range. The remaining attributes are quantified based on the models provided in the literature, which take into account several important parameters pertaining to each removal method. The means of assigning attributes to each assessment criterion is discussed in detail. A systematic comparison is performed using two different assessment schemes: Analytical Hierarchy Process and utility-based approach. A third assessment technique, namely the potential-loss analysis, is utilized to highlight the effect of risks in each removal methods

  • 14.
    Israel Nazarious, Miracle
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Vakkada Ramachandran, Abhilash
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Zorzano, María-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Centro de Astrobiología (INTA-CSIC), Torrejon de Ardoz, Madrid, Spain.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Calibration and preliminary tests of the Brine Observation Transition To Liquid Experiment on HABIT/ExoMars 2020 for demonstration of liquid water stability on Mars2019Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 162, s. 497-510Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The search for unequivocal proofs of liquid water on present day Mars is a prominent domain of research with implications on habitability and future Mars exploration. The HABIT (Habitability: Brines, Irradiation, and Temperature) instrument that will be on-board the ExoMars 2020 Surface Platform (ESA-IKI Roscosmos) will investigate the habitability of present day Mars, monitoring temperature, winds, dust conductivity, ultraviolet radiation and liquid water formation. One of the components of HABIT is the experiment BOTTLE (Brine Observation Transition To Liquid Experiment). The purposes of BOTTLE are to: (1) quantify the formation of transient liquid brines; (2) observe their stability over time under non-equilibrium conditions; and (3) serve as an In-Situ Resource Utilization (ISRU) technology demonstrator for water moisture capture. In this manuscript, we describe the calibration procedure of BOTTLE with standard concentrations of brines, the calibration function and the coefficients needed to interpret the observations on Mars.

    BOTTLE consists of six containers: four of them are filled with different deliquescent salts that have been found on Mars (calcium-perchlorate, magnesium-perchlorate, calcium-chloride, and sodium-perchlorate); and two containers that are open to the air, to collect atmospheric dust. The salts are exposed to the Martian environment through a high efficiency particulate air (HEPA) filter (to comply with planetary protection protocols). The deliquescence process will be monitored by observing the changes in electrical conductivity (EC) in each container: dehydrated salts show low EC, hydrated salts show medium EC and, liquid brines show high EC values. We report and interpret the preliminary test results using the BOTTLE engineering model in representative conditions; and we discuss how this concept can be adapted to other exploration missions.

    Our laboratory observations show that 1.2 g of anhydrous calcium-chloride captures about 3.7 g of liquid water as brine passing through various possible hydrate forms. This ISRU technology could potentially be the first attempt to understand the formation of transient liquid water on Mars and to develop self-sustaining in-situ water harvesting on Mars for future human and robotic missions.

  • 15.
    Lehner, B.A.E.
    et al.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands.
    Schlechten, J.
    Department of Computer Science, University of Geneva, Carouge, Switzerland.
    Filosa, A.
    Department of Aerospace Science and Technology (DAST), Politecnico di Milano, Milano, Italy.
    Canals Pou, A.
    Department of Materials Science and Metallurgy (CMEM), ETSEIB, Universitat Politècnica de Catalunya (UPC), Barcelona, Spain.
    Mazzotta, D.G.
    Department of Mechanical and Aerospace Engineering (DIMEAS), Politecnico di Torino, Torino, Italy.
    Spina, Francesco
    Luleå tekniska universitet.
    Teeney, L.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands. Department of Computer Science, University of Geneva, Carouge, Switzerland.
    Snyder, J.
    USRA / NASA Ames Research Center, Moffett Field, USA.
    Tjon, S.Y.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands.
    Meyer, A.S.
    Department of Biology, University of Rochester, Rochester, USA.
    Brouns, S.J.J.
    Department of Bionanoscience, TU Delft, , HZ Delft, the Netherlands.
    Cowley, A.
    European Astronaut Centre (EAC), European Space Agency (ESA), Cologne, Germany.
    Rothschild, L.J.
    NASA Ames Research Center, Moffett Field, USA.
    End-to-end mission design for microbial ISRU activities as preparation for a moon village2019Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 162, s. 216-226Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In situ resource utilization (ISRU) increasingly features as an element of human long-term exploration and settlement missions to the lunar surface. In this study, all requirements to test a novel, biological approach for ISRU are validated, and an end-to-end mission architecture is proposed. The general mission consists of a lander with a fully autonomous bioreactor able to process lunar regolith and extract elemental iron. The elemental iron could either be stored or directly utilized to generate iron wires or construction material. To maximize the success rate of this mission, potential landing sites for future missions are studied, and technical details (thermal radiation, shielding, power-supply) are analyzed. The final section will assess the potential mission architecture (orbit, rocket, lander, timeframe). This design might not only be one step further towards an international “Moon Village”, but may also enable similar missions to ultimately colonize Mars and further explore our solar system.

  • 16.
    Lehtinen, Tuomas
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Granvik, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland.
    Bellome, Andrea
    Space Research Group, Cranfield University, Cranfield, United Kingdom.
    Sánchez, Joan-Pau
    Space Research Group, Cranfield University, Cranfield, United Kingdom.
    Icarus: In-situ monitoring of the surface degradation on a near-Sun asteroid2021Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 186, s. 98-108Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Icarus is a mission concept designed to record the activity of an asteroid during a close encounter with the Sun. The primary science goal of the mission is to unravel the nontrivial mechanism(s) that destroy asteroids on orbits with small perihelion distances. Understanding the destruction mechanism(s) allows us to constrain the bulk composition and interior structure of asteroids in general. The Icarus mission does not only aim to achieve its science goals but also functions as a technical demonstration of what a low-cost space mission can do. The proposed space segment will include a single spacecraft capable of surviving and operating in the harsh environment near the Sun. The spacecraft design relies on the heritage of missions such as Rosetta, MESSENGER, Parker Solar Probe, BepiColombo, and Solar Orbiter. The spacecraft will rendezvous with an asteroid during its perihelion passage and records the changes taking place on the asteroid’s surface. The primary scientific payload has to be capable of imaging the asteroid’s surface in high resolution using visual and near-infrared channels as well as collecting and analyzing particles that are ejected from the asteroid. The payload bay also allows for additional payloads relating to, for example, solar research. The Icarus spacecraft and the planned payloads have high technology readiness levels and the mission is aimed to fit the programmatic and cost constraints of the F1 mission (Comet Interceptor) by the European Space Agency. Considering the challenging nature of the Icarus trajectory and the fact that the next F-class mission opportunity (F2) is yet to be announced, we conclude that Icarus is feasible as an F-class mission when certain constraints such as a suitable launch configuration are met. A larger mission class, such as the M class by the European Space Agency, would be feasible in all circumstances.

  • 17.
    Matelli, José Alexandre
    et al.
    São Paulo State University (UNESP), School of Engineering, Department of Energy, Av. Ariberto Pereira da Cunha, Guaratinguetá, SP, Brazil.
    Goebel, Kai
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik. NASA Ames Research Center, Intelligent Systems Division, Discovery and Systems Health, Moffett Field, CA.
    Resilience evaluation of the environmental control and life support system of a spacecraft for deep space travel2018Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 152, s. 360-369Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In deep space manned travels, the crew life will be totally dependent on the environment control and life support system of the spacecraft. A life-support system for manned missions is a set of technologies to regenerate the basic life-support elements, such as oxygen and water, which makes resilience a paramount feature of this system. The resilience of a complex engineered system is the ability of the system to withstand failures, continue operating and recover from those failures with minimum disruption. Resilient design is a new design framework on which the main goal is to quantify system resilience upfront in order to guide the design team during the conceptual design stage. In this article, we present a tool that combines a rule-based approach with a Monte Carlo-based approach to evaluate the resilience of a proposed environment control and life support system designed for deep space travel. Based on the results found, we explore a few design alternatives in order to increase system resilience.

  • 18.
    Mathanlal, Thasshwin
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Israel Nazarious, Miracle
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Vakkada Ramachandran, Abhilash
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Zorzano, Maria-Paz
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Centro de Astrobiología (CSIC-INTA), Torrejon de Ardoz, 28850, Madrid, Spain.
    Martin-Torres, Javier
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), 18100, Granada, Spain.
    Rettberg, Petra
    German Aerospace Center, Institute of Aerospace Medicine, Radiation Biology, Linder Höhe, 51147, Köln, Germany.
    Implementing bioburden reduction and control on the deliquescent hydrogel of the HABIT/ExoMars 2020 instrument2020Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 173, s. 232-239Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The HabitAbility: Brines, Irradiation and Temperature (HABIT) instrument will be part of the ExoMars 2020 mission (ESA/Roscosmos) and will be the first European In-situ Resource Utilization (ISRU) instrument capable of producing liquid water on Mars. HABIT is composed by two modules: Environmental Package (EnvPack) and Brine Observation Transition To Liquid Experiment (BOTTLE). EnvPack will help to study the current habitability conditions on Mars investigating the air and surface thermal ranges and Ultraviolet (UV) irradiance; and BOTTLE is a container with four independent vessels housing deliquescent salts, which are known to be present on Mars, where the liquid water will be produced after deliquescence. In order to prevent capillarity of deliquescent or hydrated salts, a mixture of deliquescent salts with Super Absorbent Polymer (SAP) based on polyacrylamide is utilized. This mixture has deliquescent and hydrogel properties and can be reused by applying a thermal cycle, complying thus with the purpose of the instrument. A High Efficiency Particulate Air (HEPA) grade filter made of polytetrafluroethylene (PTFE) porous membrane sandwiched between spunbounded non-woven fabric stands as a physical barrier allowing interaction between the gaseous molecules of the Martian atmosphere and the salt mixtures, and at the same time preventing the passage of any potential biological contamination from the cells to the outside or vice-versa. In addition to the physical barrier, a strict bioburden reduction and analysis procedure is applied to the hardware and the contained salt mixtures adhering to the European Cooperation for Space Standardization protocol of microbial examination of flight hardware (ECSS-Q-ST-70-55C). The deliquescent salts and the SAP products need to be properly treated independently to adhere to the planetary protection protocols. In this manuscript, we describe the bioburden reduction process utilized to sterilize the salt mixtures in BOTTLE and the assays adopted to validate the sterilization. We also describe the construction of a low-cost, portable ISO 7 cleanroom tent, exclusively designed for planetary protection tests. The sterilization process involves Dry Heat Microbial Reduction (DHMR) of the deliquescent salts and the SAP mixtures. The performance of SAP after DHMR is validated to ensure its working efficiency after sterilization. A slightly modified version of the standard swab assay is used in the validation process and a comparison is made between samples exposed to a thermal shock treatment and those without thermal shock, to determine the best assay to be applied for future space hardware utilizing such salt mixtures for planetary investigation and In-Situ Resource Utilization (ISRU). The demonstration of the compatibility of these products with the processes commonly required for space applications has implications for the future exploration of Mars.

  • 19.
    Muralidharan, Vijay
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Concurrent rendezvous control of underactuated spacecraft2017Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 138, s. 28-42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The concurrent control of spacecraft equipped with one-axis unilateral thruster and three-axis attitude actuator is considered in this paper. The proposed control law utilizes attitude control channels along with the single thrust force concurrently, for three-dimensional trajectory tracking and rendezvous with a target object. The concurrent controller also achieves orbital transfer to low Earth orbits with long range separation. To demonstrate the orbit transfer capabilities of the concurrent controller, a smooth elliptical orbit transfer trajectory for co-planar circular orbits is designed. The velocity change and energy consumption of the designed orbit transfer trajectory is observed to be equivalent to that of Hohmann transfer.

  • 20.
    Satpute, Sumeet
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Emami, Reza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik. University of Toronto, Toronto, Canada.
    Concurrent co-location maneuver planning for geostationary satellites2019Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 163, nr Part B, s. 211-224Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper details the development of a planning algorithm for multiple co-located geostationary satellites to perform station keeping and momentum unloading maneuvers concurrently. The objective is to minimize the overall fuel consumption while guaranteeing a safe separation distance between the satellites within a specific geostationary slot, as well as managing their stored angular momentum to maintain their nadir pointing orientation. The algorithm adopts the leader-follower architecture to define relative orbital elements of the satellites equipped with four gimbaled on-off electric thrusters, and solves a convex optimization problem with inequality constraints, including momentum unloading requirements, to determine the optimal maneuvers. The proposed algorithm is verified, in terms of fuel consumption, constraints enforcement and satellites performance, using numerical simulations that take into account dominant perturbations in the geostationary environment.

  • 21.
    Schmidt, Jens
    et al.
    Center for Astrophysics, Space Physics and Engineering Research (CASPER), Baylor University, 100 Research Pkwy, Waco, TX, USA. Institute of Space Systems, University of Stuttgart, Pfaffenwaldring 29, 70569 Stuttgart, Germany.
    Laufer, René
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Hyde, Truell
    Center for Astrophysics, Space Physics and Engineering Research (CASPER), Baylor University, 100 Research Pkwy, Waco, TX, USA.
    Herdrich, Georg
    Institute of Space Systems, University of Stuttgart, Pfaffenwaldring 29, 70569 Stuttgart, Germany.
    The IPG6-B as a research facility to support future development of electric propulsion2022Ingår i: Acta Astronautica, ISSN 0094-5765, E-ISSN 1879-2030, Vol. 196, s. 432-441Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The inductively-heated plasma generator IPG6-B at Baylor University has been established and characterized in previous years for use as a flexible experimental research facility across multiple applications. The system uses a similar plasma generator design to its twin-facilities at the University of Stuttgart (IPG6-S) and the University of Kentucky (IPG6-UKY). The similarity between these three devices offers the advantage to reproduce results and provides comparability to achieve cross-referencing and verification. Sub- and supersonic flow conditions for Mach numbers between Ma = 0.3 — 1.4 have been characterized for air, argon, helium and nitrogen using a pitot probe. Overall power coupling efficiency as well as specific bulk enthalpy of the flow have been determined by calorimeter measurements to be between η = 0.05 — 0.45 and hs = 5 — 35 MJ kg-1 respectively depending on gas type and pressure. Electron temperatures of Te = 1 — 2 eV and densities ne = 1018 — 1020 m-3 have been measured using an electrostatic probe system. At Baylor University, laboratory experiments in the areas of astrophysics, geophysics as well as fundamental research on complex (dusty) plasmas are planned. The study of fundamental processes in low-temperature plasmas connects directly to electric propulsion systems. Most recent experiments include the study of dusty plasmas and astrophysical phenomena and the interaction of charged dust with electric and magnetic fields. In this case, dust can be used as a diagnostic for such fields and can reveal essential information of the magneto-hydrodynamics in low-temperature plasmas. Although some of these goals require further advancement of the facility, it is proposed that several phenomena relevant to electric propulsion as well as to other fields of plasma physics can be studied using the existing facility.

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