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This dissertation covers the development and calibration of the Jovian plasma Dynamics and Composition analyzer (JDC). JDC is together with five other sensors a part of the Particle Environment Package (PEP), one of the payloads of the European Space Agency's JUpiter ICy moons Explorer (JUICE) mission. The JUICE mission is designed to broaden our understanding of the Jovian system including Jupiter, the four Galilean moons (Io, Europa, Ganymede and Callisto) and Jupiter's vast magnetosphere. JUICE is planned to launch in 2023. The PEP payload will study the plasma environment around Jupiter and its moons in great detail. As one of the sensors of PEP, JDC will measure the energy distribution of positive and negative ions as well as electrons in an energy range from a few eV/q up to 35keV/q. The field of view covered by JDC spans over a full hemisphere. JDC also determines the mass of particles using the time-of-flight principle. Alternatively, there is the possibility to determine the distribution of particle arrival times to study their distribution in the time domain. In this thesis, ion-optical, mechanical, electrical, thermal, radiation shielding and instrument operation related design solutions are presented and discussed. Special attention was paid to the performance of the channel electron multipliers used as time-of-flight start detectors. To verify their performance throughout the whole mission, a full lifetime test for these detectors was successfully performed. As a result of this test a qualitative performance model for channel electron multipliers was developed. Another experiment included in this work is the determination of the residual gas pressure evolution inside of JDC. A sufficiently low residual gas pressure is required for safe operation of JDC's high voltage systems. Finally, the performance of the JDC linear electric field reflectron was verified using a dedicated prototype. The last part of this work describes the methods used for instrument calibration and first results of the calibration of the flight spare model of JDC, the unit that will fly to Jupiter, are presented. Den här avhandlingen behandlar utvecklingen och kalibreringen av instrumentetJovian plasma Dynamics and Composition analyzer (JDC). JDC utgör tillsammans med fem andra sensorer Particle Environment Package (PEP), som är ett av experimenten på European Space Agency:s rymdsond Jupiter Icy moons Explorer (JUICE). JUICE uppdrag är att bredda och fördjupa vår kunskap om Jupiter-systemet. Rymdsonden ska skjutas upp 2023 och studera Jupiter, Jupiters magnetosfär och de fyra Galileiska månarna (Io, Europa, Ganymedes och Callisto). Instrumentpaketet PEP är konstruerat för att undersöka plasmamiljön kring Jupiter och dess månar i detalj. Sensorn JDC har som sin specifika uppgift att observera energifördelningen hos positiva och negativa joner samt elektroner i ett energiområde från några få eV/q (elektronvolt per laddningsenhet) upp till 35 keV/q. JDC:s synfält är en hel hemisfär och instrumentet använder flygtidsprincipen för att bestämma massorna hos de partiklar som observeras. Det finns också en möjlighet att istället registrera partiklarnas ankomsttider för att titta på fördelningen i tidsdomänen. I avhandlingen presenteras jonoptiska, mekaniska, elektriska och termiska konstruktionslösningar för JDC. Aspekter relaterade till strålningsskärmning och drift av instrumentet diskuteras också. Vi tittar särskilt på prestandan hos de kanalelektronmultiplikatorer som används som startdetektorer i flygtidssystemet. För att undersöka hur de kommer att fungera under den långa expeditionen har ett livstidstest utförts. Utgående från resultaten har en kvalitativ prestandamodell tagits fram. Ett annat experiment som avhandlingen behandlar är undersökningen av hur residualgastrycket utvecklas inuti JDC. För att de högspänningssystem som finns inuti instrumentet ska fungera utan risk för överslag måste trycket vara tillräckligt lågt. Slutligen diskuteras användningen av en särskild prototyp för att verfiera funktionaliteten hos den så kallade ’reflektronen’, en av JDC:s centrala delar. Sista delen av avhandlingen beskriver metoder som använts för kalibrering av instrumentet och de första resultaten från kaliberingen av det exemplar (den modell) av JDC som faktiskt kommer att flyga till Jupiter. Various Pagination.

The JUpiter Icy moons Explorer (JUICE) will investigate Ganymede's and Callisto's surfaces and subsurfaces from orbit to explore the geologic processes that have shaped and altered their surfaces by impact, tectonics, possible cryovolcanism, space weathering due to micrometeorites, radiation and charged particles as well as explore the structure and properties of the icy crust and liquid shell (Grasset et al., 2013). The best possible synergy of the JUICE instruments is required to answer the major science objective of this mission and to fully exploit the potential of the JUICE mission. Therefore, the JUICE team is aiming to define high priority targets on both Ganymede's and Callisto's surfaces to support the coordination of the planning activities by the individual instrument teams. Based on the science objectives of the JUICE mission and the most recent knowledge of Ganymede's and Callisto's geologic evolution we propose a collection of Regions of Interest (RoIs), which characterize surface features and terrain types representing important traces of geologic processes, from past and/or present cryovolcanic and tectonic activity to space weathering processes, which are crucial to understand the geologic evolution of Ganymede and Callisto. The proposed evaluation of RoIs is based on their scientific importance as well as on the opportunities and conditions to observe them during the currently discussed mission profile.

The JUpiter Icy moons Explorer (JUICE) will investigate Ganymede's and Callisto's surfaces and subsurfaces from orbit to explore the geologic processes that have shaped and altered their surfaces by impact, tectonics, possible cryovolcanism, space weathering due to micrometeorites, radiation and charged particles as well as explore the structure and properties of the icy crust and liquid shell (Grasset et al., 2013). The best possible synergy of the JUICE instruments is required to answer the major science objective of this mission and to fully exploit the potential of the JUICE mission. Therefore, the JUICE team is aiming to define high priority targets on both Ganymede's and Callisto's surfaces to support the coordination of the planning activities by the individual instrument teams. Based on the science objectives of the JUICE mission and the most recent knowledge of Ganymede's and Callisto's geologic evolution we propose a collection of Regions of Interest (RoIs), which characterize surface features and terrain types representing important traces of geologic processes, from past and/or present cryovolcanic and tectonic activity to space weathering processes, which are crucial to understand the geologic evolution of Ganymede and Callisto. The proposed evaluation of RoIs is based on their scientific importance as well as on the opportunities and conditions to observe them during the currently discussed mission profile.

The JUpiter Icy moons Explorer (JUICE) will investigate Ganymede's and Callisto's surfaces and subsurfaces from orbit to explore the geologic processes that have shaped and altered their surfaces by impact, tectonics, possible cryovolcanism, space weathering due to micrometeorites, radiation and charged particles as well as explore the structure and properties of the icy crust and liquid shell (Grasset et al., 2013). The best possible synergy of the JUICE instruments is required to answer the major science objective of this mission and to fully exploit the potential of the JUICE mission. Therefore, the JUICE team is aiming to define high priority targets on both Ganymede's and Callisto's surfaces to support the coordination of the planning activities by the individual instrument teams. Based on the science objectives of the JUICE mission and the most recent knowledge of Ganymede's and Callisto's geologic evolution we propose a collection of Regions of Interest (RoIs), which characterize surface features and terrain types representing important traces of geologic processes, from past and/or present cryovolcanic and tectonic activity to space weathering processes, which are crucial to understand the geologic evolution of Ganymede and Callisto. The proposed evaluation of RoIs is based on their scientific importance as well as on the opportunities and conditions to observe them during the currently discussed mission profile.

The Ganymede Laser Altimeter (GALA) is one of the ten scientific instruments selected for the Jupiter Icy Moons Explorer (JUICE) mission currently implemented under responsibility of the European Space Agency (ESA). JUICE is scheduled for launch in mid 2022; arrival at Jupiter will be by end of 2029 with the nominal science mission—including close flybys at Ganymede, Europa, and Callisto and a Ganymede orbit phase—ending by mid 2033. GALA’s main objective is to obtain topographic data of the icy satellites of Jupiter: Europa, Ganymede, and Callisto. By measuring the diurnal tidal deformation of Ganymede, which crucially depends on the decoupling of the surface ice layer from the deep interior by a liquid water ocean, GALA will obtain evidence for (or against) a subsurface ocean in a 500 km orbit around the satellite and will provide constraints on Ganymede’s ice shell thickness. In combination with other instruments, it will characterize the morphology of surface units on Ganymede, Europa, and Callisto providing not only topography but also surface roughness and albedo (at 1064 nm) measurements. GALA is a single-beam laser altimeter operating with up to 50 Hz (nominal 30 Hz) shot frequency at a wavelength of 1064 nm and pulse lengths of 5.5 ± 2.5 ns using a Nd:YAG laser. The return pulse is detected by an Avalanche Photo Diode (APD) with 100 MHz bandwidth and is digitized at a sampling rate of 200 MHz providing range measurements with a subsample resolution of 0.1 m and surface roughness measurements from pulse-shape analysis on the scale of the footprint size of about 50 m at 500 km altitude. The instrument is developed in collaboration of institutes and industry from Germany, Japan, Switzerland, and Spain. © 2019, CEAS., Financial support was provided under grant 50 QJ 1401 on behalf of the DLR Space Administration by the German Bundesministerium fur Wirtschaft und Energie. This research has been supported by the Spanish Ministerio de Economia y Competitividad under Contract ESP 2016-76076-R.

We designed a tool allowing irradiation of large samples over a surface of A5 size dimension by means of a 2.5 MeV Pelletron electron accelerator. in situ electrical measurements (I-V, conductivity, etc.) can also be performed, in the dark or under illumination, to study radiation effects in materials. Irradiations and electrical measurements are achievable over a temperature range from 100 K to 300 K. The setup was initially developed to test real-size triple junction solar cells at low temperature within the framework of the ESA’s JUICE mission. It will be made available to users at the beginning of 2017. After a brief description of the SIRIUS irradiation facility hosted at Laboratoire des Solides Irradiés (LSI), this paper gives detailed information about the Large Surface Irradiated-Cell (LSIC) device. Preliminary results obtained during the ongoing qualification phase of the setup are also discussed.

The JUpiter ICy moons Explorer mission of the European Space Agency, that will be launched in the year 2022, will study the geodesy and physical characteristics of Jupiter and its icy moons Europa, Callisto and Ganymede. The final phase of this mission, planned for the year 2032, is still under investigation and foresees phases in circular orbit around Ganymede. In this paper two types of science orbits around Ganymede, that optimize the observational performances and the probe life-time, are proposed. While the first type allows, at “zero cost”, the obtaining of repeated observations of a given point of the surface, the second type, with a limited cost, adds to the periodicity of observation, the condition of synchronism with the Sun. This synchronism permits both the achievement of a condition of permanent sunlight for the probe, thus leading to an extension of the mission duration, and a minimization of the variations of spectral signature due to the Sun's position.

The JUpiter Icy moons Explorer (JUICE) will investigate Ganymede's and Callisto's surfaces and subsurfaces from orbit to explore the geologic processes that have shaped and altered their surfaces by impact, tectonics, possible cryovolcanism, space weathering due to micrometeorites, radiation and charged particles as well as explore the structure and properties of the icy crust and liquid shell (Grasset et al., 2013). The best possible synergy of the JUICE instruments is required to answer the major science objective of this mission and to fully exploit the potential of the JUICE mission. Therefore, the JUICE team is aiming to define high priority targets on both Ganymede's and Callisto's surfaces to support the coordination of the planning activities by the individual instrument teams. Based on the science objectives of the JUICE mission and the most recent knowledge of Ganymede's and Callisto's geologic evolution we propose a collection of Regions of Interest (RoIs), which characterize surface features and terrain types representing important traces of geologic processes, from past and/or present cryovolcanic and tectonic activity to space weathering processes, which are crucial to understand the geologic evolution of Ganymede and Callisto. The proposed evaluation of RoIs is based on their scientific importance as well as on the opportunities and conditions to observe them during the currently discussed mission profile.