This session aims to inform the geoscientists and engineers regarding new and/or improved instrumentation and methods for space and planetary exploration, as well as about their novel or established applications.
The session is open to all branches of planetary and space measurement tools and techniques, including, but not limited to: optical, electromagnetic, seismic, acoustic, particles, and gravity.
Please, kindly take contact with the conveners if you have a topic that may be suitable for a review talk.
This session is also intended as an open forum, where discussion between representatives of different fields within planetary, space and geosciences will be strongly encouraged, looking for a fruitful mutual exchange and cross fertilization between scientific areas.

Co-organized by PS6
Convener: Santo PronteraECSECS | Co-conveners: Bernard Foing, Håkan Svedhem
| Attendance Mon, 04 May, 14:00–15:45 (CEST)

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Chat time: Monday, 4 May 2020, 14:00–15:45

D809 |
Sylvain Ranvier, Michel Anciaux, Jean-Pierre Lebreton, and Johan De Keyser

The Sweeping Langmuir Probe (SLP) instrument, that uses a novel measurement technique to take into account spacecraft charging effects, has been developed at the Royal Belgian Institute for Space Aeronomy. SLP will fly on board the ESA scientific in-orbit demonstrator PICASSO together with the hyper-spectral imager VISION. PICASSO, a triple unit CubeSat, will be launched in March 2020. The goal of the mission is to prove the feasibility of performing true science (with limited extent) with a nano-satellite and demonstrate the very low cost / science ratio with respect to big missions. SLP will allow a global monitoring of the ionosphere with a maximum spatial resolution of the order of 150 m.  The main goals are to study the ionosphere-plasmasphere coupling, the subauroral ionosphere and corresponding magnetospheric features together with auroral structures and polar caps, by combining SLP data with other complementary data sources (space- or ground-based instruments). SLP can measure plasma density from 1e8/m³ up to 1e13/m³ and electron temperature up to 15 000 K.

We will present the main results from the validation tests performed in the plasma chamber at ESTEC together with comparisons with particle-in-cell (PIC) simulations performed with SPIS (Spacecraft Plasma Interaction System).

How to cite: Ranvier, S., Anciaux, M., Lebreton, J.-P., and De Keyser, J.: Validation and characterisation of the Sweeping Langmuir Probe (SLP) instrument for the PICASSO mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14126, https://doi.org/10.5194/egusphere-egu2020-14126, 2020.

D810 |
Johan De Keyser, Marius Echim, Sylvain Ranvier, Thomas Chambon, Björn Ordoubadian, and Norbert Lemke

Spacecraft that aim to study the atmosphere of a planetary object through in situ sampling face the problem of strong atmospheric drag. In order not to compromise mission lifetime, the orbit can be designed so that repeated deep dives into the upper atmosphere are performed to sample atmospheric density, pressure, and composition down to relatively low altitudes. During such deep dives, ram-facing instruments, such as ion and neutral wind instruments, in particular are exposed to a severe heating flux.

The present contribution focuses on the particular case of the neutral Cross-Wind Sensor (CWS) under study for the Daedalus Earth Explorer 10 mission led by ESA, which will sample the Earth’s upper atmosphere during its perigee passes at an altitude currently planned to be in the 110 to 140 km range. Thermal simulations are presented that show the transient heat loads on the CWS instrument. It is shown that, with an appropriate materials choice, these heat loads can be dealt with in a satisfactory manner.

How to cite: De Keyser, J., Echim, M., Ranvier, S., Chambon, T., Ordoubadian, B., and Lemke, N.: Thermal behaviour of ram-facing instruments during deep dives into a planetary atmosphere: The case of Daedalus/CWS, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4409, https://doi.org/10.5194/egusphere-egu2020-4409, 2020.

D811 |
Martina Föhn, Marek Tulej, André Galli, Audrey Helena Vorburger, Davide Lasi, Peter Wurz, Pontus Brandt, and Stas Barabash

Investigation of habitable environments is one of the main objectives in upcoming space missions. The JUICE mission will investigate Jupiter’s environment in the solar system and its icy moons Ganymede, Callisto and Europa as examples for potentially habitable worlds around a gas giant. The Particle Environment Package (PEP) on the JUICE satellite will investigate Jupiter’s icy moons and their environment. As part of PEP, the Neutral gas and Ion Mass spectrometer (NIM) will measure the chemical composition of the exospheres of the icy moons. These measurements give information about the surface composition of the moons and will set constraints on their formation processes.

NIM is a Time of Flight mass spectrometer with two entrances for neutral particles and ions. The gas enters the instrument from spacecraft ram direction. With the open source neutral particles and ions enter the ionisation region directly. With the closed source neutral particles get thermalized using an antechamber before entering the ion source. Particles entering with higher velocity are therefore easier to detect through the antechamber.

Initial performance tests with the NIM Protoflight Model (PFM) were done. The storage capability of the ion source was tested, the functionality of the antechamber was verified and we measured masses up to 642 u to demonstrate the high-mass performance of NIM. Furthermore, different subunits of the NIM instrument were successfully tested, such as the redesigned ion source and flight electronics connected with the NIM sensor head.

How to cite: Föhn, M., Tulej, M., Galli, A., Vorburger, A. H., Lasi, D., Wurz, P., Brandt, P., and Barabash, S.: Development of the NIM Mass spectrometer for Exploration of Jupiter’s Icy Moons Exospheres, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2955, https://doi.org/10.5194/egusphere-egu2020-2955, 2020.

D812 |
Frank Maiwald, Jurij Simcic, Dragan Nikolic, Anton Belousov, and Stojan Madzunkov

The JPL Mass Spectrometer Team develops components and instruments based on a Paul quadrupole ion trap mass spectrometer (QIT-MS) for Earth and space applications. Over the past 20 years, the team has miniaturized the QIT-MS and verified its performance successfully for the International Space Station. The technology was demonstrated with the recent delivery of the first Spacecraft Atmosphere Monitor (S.A.M.) to the International Space Station (ISS).

The next step is to build a QIT-MS intendent to investigate the lunar exosphere via a funded ROSES 2019, DALI/NASA proposal over the next three years.

The QIT-MS will be the first in-situ lunar mass spectrometer capable of identifying and quantifying exosphere species (ex. H, H2, 3He, 4He, Ne, N2, O2, Ar, CH4, CO, CO2, Kr, Xe, OH, H2O) with abundance greater than 10 molecules/cm3 [1]. The combination of low mass (7.5 kg), low power (max. 30W with heater bulb on), high sensitivity (0.003 counts/cm3/sec), and ultrahigh precision (1.7 x 10-10 Torr, Kr measured continuously for 7 hours yielded a 0.6 ‰ precision on the 86Kr/84Kr ratio) will provide an unpreceded inside of the scientific processes in the lunar exosphere.

Other implementation approaches will be discussed, which entail the development of different frontends to expand applications for dense atmospheres (ex. Venus) or liquids (ex. ocean worlds). Most of these developments can be used to determine contaminants in the air, water, or volatile in solids.

[1] G. Avice, A. Belousov, K. A. Farley, S. M. Madzunkov, J. Simcic, D. Nikolic, M. R. Darrach and C. Sotin, “High-precision measurements of krypton and xenon isotopes with a new static-mode quadrupole ion trap mass spectrometer,” JAAS, Vol 34, January 2019


Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109


How to cite: Maiwald, F., Simcic, J., Nikolic, D., Belousov, A., and Madzunkov, S.: Compact High Resolution QIT-Mass Spectrometers for Lunar and Planetary Applications, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3177, https://doi.org/10.5194/egusphere-egu2020-3177, 2020.

D813 |
| Highlight
Maxim Mokrousov, Igor Mitrofanov, Alexander Kozyrev, Maxim Litvak, Alexey Malakhov, Anton Sanin, Vladislav Tretyakov, Dmitry Golovin, and Artem Anikin

The method of remote neutron and gamma spectrometry of bodies in the solar system (the Moon, Mars, and Mercury) has been used for several decades to estimate the nuclear composition of these objects and the hydrogen abundance in their subsurface layers. It is known that many solid planets of Solar system with thin atmospheres, its moons, small bodies and even comets due to bombardment by heavy nucleus of Galactic Cosmic Rays (GRS) produce neutron albedo and characteristic gamma lines. Detection of escaping gammas and neutrons (remote sensing from an orbit or in situ) bringing an information about elemental composition of the subsurface and hydrogen-containing elements (as deep as tens of centimeters). Currently we can classify all nuclear planetology instruments by the field of view (uncollimated and collimated) and by type of soil irradiation (passive – using GRS, and active – using pulsing neutron generator onboard), each of those methods has pros and cons and all of them will be presented. Also, future nuclear planetology instruments and method in design will be presented.

How to cite: Mokrousov, M., Mitrofanov, I., Kozyrev, A., Litvak, M., Malakhov, A., Sanin, A., Tretyakov, V., Golovin, D., and Anikin, A.: Instrumentation for Nuclear Planetology: Present and Future, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8870, https://doi.org/10.5194/egusphere-egu2020-8870, 2020.

D814 |
Iannis Dandouras, Pierre Devoto, Johan De Keyser, Yoshifumi Futaana, Ruth Bamford, Graziella Branduardi-Raymont, Dragos Constantinescu, Jean-Yves Chaufray, Jonathan Eastwood, Marius Echim, Benjamin Grison, David Hercik, Anna Milillo, Rumi Nakamura, Lubomír Přech, Elias Roussos, Štěpán Štverák, André Laurens, Josef Winter, and Matt G. G. T. Taylor and the SP4GATEWAY Team

The Deep Space Gateway is a crewed platform that will be assembled and operated in the vicinity of the Moon by ESA and its international partners in the early 2020s and will offer new opportunities for fundamental and applied scientific research. The Moon is a unique location to study the deep space plasma environment, due to the absence of a substantial intrinsic magnetic field and the direct exposure to the solar wind, galactic cosmic rays (GCRs) and solar energetic particles (SEPs). However, 5-6 days each orbit, the Moon crosses the tail of the terrestrial magnetosphere facilitating the in-situ study of the terrestrial magnetotail plasma environment as well as atmospheric escape from the ionosphere. When back outside of the magnetosphere, a variety of these and other phenomena, e.g. those driving solar-terrestrial relationships, can be investigated through remote sensing using a variety of imaging techniques. Most importantly, the lunar environment offers a unique opportunity to study the interaction of the solar wind and the magnetosphere with the lunar surface and the lunar surface-bounded exosphere. In preparation of the scientific payload of the Deep Space Gateway, we have undertaken a conceptual design study for a Space Plasma Physics Payload Package onboard the Gateway (SP4GATEWAY). The main goal is first to provide a science rationale for hosting space plasma physics instrumentation on the Gateway and to translate that into a set of technical requirements. A conceptual payload design, that identifies a strawman payload and is compatible with the technical requirements, is then put forward. The final outcome of this project, which is undertaken following an ESA AO, is an implementation plan for this space plasma physics payload package.

How to cite: Dandouras, I., Devoto, P., De Keyser, J., Futaana, Y., Bamford, R., Branduardi-Raymont, G., Constantinescu, D., Chaufray, J.-Y., Eastwood, J., Echim, M., Grison, B., Hercik, D., Milillo, A., Nakamura, R., Přech, L., Roussos, E., Štverák, Š., Laurens, A., Winter, J., and Taylor, M. G. G. T. and the SP4GATEWAY Team: SP4GATEWAY: a Space Plasma Physics Payload Package conceptual design for the Deep Space Gateway Lunar Orbital Platform, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10565, https://doi.org/10.5194/egusphere-egu2020-10565, 2020.

D815 |
| Highlight
James Burke

Food production will of course be critical for lunar living. The leaders will be growing plants first in small quantities for research to see how they perform in the lunar environment (radiation, partial gravity), then to supplement key nutrients the existing lunar diet might lack over time (likely with pick and eat type crops such as leafy vegetables, fruiting plants like peppers and micro greens) and finally to replace calories and associated up-mass at some future time based on the expansion of human presence and activity (staple crops such as potatoes, wheat etc.). Here we discuss a start-up proof-of-concept farm where tests can be carried out to validate plans for a later, full-scale farm. The concept will take advantage of previous work on Earth and in low earth orbit including experiments aboard the International Space Station, and will be designed for variation of all relevant parameters. Examples of variables will be the fractional duration and intensity of sunlight or artificial light sent to trays of growing crops from a primary mirror tracking the Sun around the horizon and the organization of planting, fertilizing and harvesting of products. It’s expected that LED lighting will provide the light source in a majority of concept applications. LED’s allow us to tailor specific light recipies optimal for the plant types we select. This is how things are done today in Controlled Environment Agriculture (CEA) on Earth. The organization and sequencing of planting operations is important as is water and nutrient delivery, harvesting and waste product recycling. The role automation, robotics and food safety are very important since we are likely not going to be sending farmers anytime soon and crew time for lunar exploration will be the priority. Ultimately we must plan to include the farm as part of a bioregenerative life support. The crops will be partly spread out on the surface and partly arranged in a sloping list, covered by a transparent cover equipped with provisions for cleaning. Among the concepts to be tested will be the delivery of water from a source in a lunar mine.






How to cite: Burke, J.: First Farm for Lunar Polar Base, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22255, https://doi.org/10.5194/egusphere-egu2020-22255, 2020.

D816 |
Xiaowen Hu, Kai Liu, Xin Li, Zonghao Pan, Yiren Li, Xinjun Hao, and Tielong Zhang

As one of the objectives for China’s First Mars Exploration Mission (CMM-1), the magnetic field in Mars’ near space will be measured by the Magnetometer onboard of the Orbiter (MAG-O), which consists of two fluxgate sensors and one electronic box. We conducted pre-flight calibration test to determine the temperature dependent offset and the correction matrix, which composed of sensitivities and non-orthogonality parameters. Two sets of ground validation experiments were also executed under limited condition to confirm the consistency and mutual interference of the two sensors, respectively. The results show that MAG-O meets the requirements of CMM-1 mission. This paper will introduce the procedure and results of pre-flight calibration and validation test.

How to cite: Hu, X., Liu, K., Li, X., Pan, Z., Li, Y., Hao, X., and Zhang, T.: Pre-flight Calibration and validation test of CMM-1 Fluxgate Magnetometer MAG-O, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2090, https://doi.org/10.5194/egusphere-egu2020-2090, 2020.

D817 |
Yiren Li, Bin Miao, Xinjun Hao, Tielong Zhang, and Yuming Wang

For the calibration of space plasma analyzers, in particular low-energy ion mass spectrometers, a low energy ion beam system was developed. The positive ion beam is produced by a hot-cathode penning source and modified by a series of electrostatic lenses. And a 75 mm diameter 2-D imaging system and a Faraday cup mounted on movable arms are used for ion beam diagnostics. With protons as primary species, the system provides an ion beam in the energy range of 1 eV - 1000 eV with a large area ( ~ 50 cm2), highly parallel ( ± 0.5°), and spatially uniform ( ± 5%).

How to cite: Li, Y., Miao, B., Hao, X., Zhang, T., and Wang, Y.: A 1 eV - 1000 eV ion beam system designed for the calibration of low-energy ion mass spectrometers, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6461, https://doi.org/10.5194/egusphere-egu2020-6461, 2020.

D818 |
Zonghao Pan, Guoqiang Wang, LiFei Meng, and Tielong Zhang

The zero offset of the fluxgate magnetometer in satellite orbit will be changed due to several factors. For this reason, the Davis-Smith method is proposed to calculate the zero compensation of the magnetometer based on the feature that the shear Alfvén waves do not change the total magnetic field strength. In fact, there is no pure Alfvén waves in the interplanetary space. In this paper, numerical simulation is used to analyze the influence of the amplitude, period and phase of the Alfvén waves and the time length of the data window on the zero offset of the magnetometer calculated by the Davis-Smith method in the presence of weak compressional waves. We find that Alfvén waves can produce a non-negligible error in the calculation of zero compensation only when its period is the same as the period of the compressional wave. The greater the amplitude of Alfvén waves, the smaller the error of the zero offset. The error of the zero offset is also affected by the initial phase of the Alfvén wave. In addition, the error of the zero offset tends to decrease to its true value for the longer the data window length.

How to cite: Pan, Z., Wang, G., Meng, L., and Zhang, T.: Influence of Alfvénic characteristics on calibration of satellite magnetometer, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-7866, https://doi.org/10.5194/egusphere-egu2020-7866, 2020.

D819 |
Henriette Trollvik, Ingrid Mann, Ove Havnes, Sveinung Olsen, and Yngve Eilertsen

Meteors ablation is a source of dust particles in the upper atmosphere. The remnants of meteor ablation that prevail in the mesosphere condense to nm-sized particles, denoted as Meteoric Smoke Particles (MSPs). Theory suggest that MSPs act as condensation nuclei for ice particles in the summer mesosphere, which form during summer months around the mesopause at high and mid latitudes. They are related to mesospheric phenomena such as the Noctilucent Clouds, Polar Mesospheric Summer and Winter Echoes (PMSE/PMWE). However, due to their altitude location, the only means of in situ measurement is with rocket experiments. There have been several attempts to collect these MSP particles with probes on rockets over the years, but no conclusive results have been reported so far.

UiT have proposed a new sample collector, the MEteoric Smoke Sampler (MESS). We report on the progress of the work that has focused on the design of the detector and simulation of the entry and impact of dust onto the detector. The focus of the planned measurements is on collecting ice particles, since the airflow affect them less than smaller MSPs. Estimations of the collection surface properties and impact energy are presented. An estimate of the expected mass in the traversed volume of one collecting plate, diameter of 3 mm diameter over 1 km, suggest that the volume contains ~1e8 particles. This corresponds to a mass of 7e16 amu. These estimates are made assuming spherical particles with average density 2.8 g per m3 and radius 1 nm, and an MSP density of 1e10 per m3. 

How to cite: Trollvik, H., Mann, I., Havnes, O., Olsen, S., and Eilertsen, Y.: Design considerations for a dust collector on mesospheric rocket, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9298, https://doi.org/10.5194/egusphere-egu2020-9298, 2020.

D820 |
Philipp Wittmann, Martin Wieser, Florian Trost, and Stas Barabash

The Jovian plasma Dynamics and Composition analyzer (JDC), which is part of the Particle Environment Package (PEP) on board of the JUICE spacecraft, uses high voltages up to 5kV, during operations. These high voltages are used in the ion-optical part of the instrument, where the strongest electrical fields are encountered. Preventing internal high voltage discharges in this region is a key design driver. For this reason, a design rule of keeping the field strength <3kV/mm is applied. However, the dielectric strength of a vacuum gap has a pronounced minimum much below the 3kV/mm design rule at the Paschen minimum at about 10-2 to 1 mbar. To successfully operate using the <3kV/mm design rule, the sensor needs proper venting of its inner volume to get the internal pressure significantly below the Paschen minimum pressure.

Below the Paschen minimum pressure the gas flow in the instrument is a non-collisional molecular flow. The time spent to further reduce pressure inside of the instrument when the instrument is exposed to vacuum (e.g. in space or in a test facility) depends on the internal outgassing source strength, the temperature and the geometric shape of the outgassing path.

We determine the time constants of the pressure reduction in molecular flow regime by placing micro pirani pressure sensors inside critical volumes of real instruments.

We compare the outgassing performance of the Miniature Ion Precipitation Analyzer (MIPA) on Bepi Colombo with the JDC sensor. Measurements showed too long outgassing time constants for JDC in order to be able to operate the instrument during the very time constraint on-ground test campaign where only approximately 3 days are available to reach a save vacuum of <10-5 mbar inside of the instrument. We present the implemented solution to improve outgassing performance of JDC and show it is sufficient for the on-ground test campaign.

How to cite: Wittmann, P., Wieser, M., Trost, F., and Barabash, S.: Pressure evolution inside the high voltage modules of plasma instrumentation when exposed to vacuum during ground test campaigns or after launch to space, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19066, https://doi.org/10.5194/egusphere-egu2020-19066, 2020.

D821 |
Kai Liu, Yiren Li, and Xin Li

Detections for space environment are crucial for monitoring the safety of satellites, while the parameters of space plasma are fundamental. Thus, we developed a spectrometer onboard of geostationary satellites, and it can measure the low energy ion's 3-D energy spectrum with a single sensor. To ensure the performance of the instrument, environmental tests, such as impulse test, vibration test and thermal test, were proceeded. Furthermore, a fully calibration test has been carried out to obtain all the scaling parameters. In this paper, the facilities and processes of the calibration test will be illustrated in detail, and the test's results indicate that our spectrometer will function well in the geostationary orbit.

How to cite: Liu, K., Li, Y., and Li, X.: Calibration Test for Low Energy Ion Spectrometer onboard of Geostationary Satellites, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19282, https://doi.org/10.5194/egusphere-egu2020-19282, 2020.

D822 |
Alessandro Retinò and the JUICE SCM Team

The JUpiter ICy moons Explorer (JUICE) mission is the first large-class (L1) mission in ESA Cosmic Vision. JUICE is planned for launch in 2022 with arrival at Jupiter in 2029 and will spend at least four years making detailed observations of Jupiter’s magnetosphere and of three of its largest moons (Ganymede, Callisto and Europa). The Radio and Plasma Wave Investigation (RPWI) consortium will carry the most advanced set of electric and magnetic fields sensors ever flown in Jupiter’s magnetosphere, which will allow to characterize the radio emission and plasma wave environment of Jupiter and its icy moons. Here we present the scientific objectives and the technical features of the Search Coil Magnetometer (SCM) of RPWI. SCM will provide for the first time high-quality three-dimensional measurements of magnetic field fluctuations’ vector in the frequency range 0.1 Hz – 20 kHz within Jupiter’s magnetosphere. High sensitivity (~ 4 fT / √Hz  at 4 kHz) will be assured by combining an optimized (20 cm long) magnetic transducer with a low-noise (4 nV / √Hz  ) ASICs pre-amplifier for the front-end electronics. Perturbations by the spacecraft are strongly reduced by accommodating SCM more at ~ 10 m away from the spacecraft on the JUICE magnetometer boom. The combination of high sensitivity and high cleanliness of SCM measurements will allow unpreceded studies of waves and turbulence down to kinetic scales, in particular in key regions such as the magnetopause, the auroral region and the magnetotail current sheet of Ganymede’s magnetosphere. This will lead to important advances in understanding wave-particle interaction and particle energization mechanisms in Jupiter’s magnetosphere.

How to cite: Retinò, A. and the JUICE SCM Team: The Search-Coil Magnetometer onboard the ESA JUICE mission, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21172, https://doi.org/10.5194/egusphere-egu2020-21172, 2020.

D823 |
Andrey Fedorov, Rituparna Baruah, and Jean Rubiella Romeo

Both Solar Orbiter and Jupiter Icy moon Explorer (JUICE) are long-life ESA missions, which should work in extremely difficult space environment. A very high thermal load up to 13 Solar constants will affect Solar Orbiter, and JUICE will experience a high penetration radiation influence in the Jupiter magnetosphere. The plasma packages of these missions, dedicated mostly for detection of low energy (between 1eV and 50 keV) ions and electrons shall accept a very high dynamic range of the incident charged particle flow. All these circumstances motivate us to use the Channel Electron
Multiplier (CEM) as detectors in both missions. CEMs are a conventional low energy charged particle and X-ray detectors that have been used fore many early space missions. Later, they were forced out by Micro-Channel Plates (MCP), which
allow to provide an image of the particle distribution. But for such challenge missions as Solar Orbiter and JUICE we have to come back to CEMs because they 1) less sensible to the penetrating radiation 2) have much wide dynamical
range, 3) have much longer lifetime than MCPs. 
The detector lifetime is, actually, the maximum particles number accumulated by detector until its efficiency becomes too low. And this detector feature is critical for Solar Orbiter and JUICE missions.
To check the lifetime of CEMs, for different thermal conditions also, we have made a dedicated experimental setup. We irradiated several CEM samples by a strong electron flux, continuously measuring the CEM gain and keeping 80°C on
the sample. The final total number of events, detected by each CEM was equivalent to two Solar Orbiter nominal mission duration.
The detailed analysis of the experimental data show that the visible degradation of CEMs gain is a function of the vacuum level in the vicinity of the CEM and its outgassing efficiency. If we normalize the CEM gain to the vacuum, expected in the flight, we will see that the pure, completely outgassed CEM can accumulate ten Coulombs of charge without any gain degradation. But in the beginning of the flight, we have to expect very fast gain degradation because of the CEM self-cleaning.

How to cite: Fedorov, A., Baruah, R., and Rubiella Romeo, J.: Lifetime of Channel Electron Multipliers dedicated to Plasma Instruments for Solar Orbiter and JUICE ESA missions, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10788, https://doi.org/10.5194/egusphere-egu2020-10788, 2020.

D824 |
Supriya Chakrabarti, Sunip Mukherjee, Timothy Cook, and Jeffrey Baumgardner

Ground based observations have indicated that at times the lunar Sodium atmosphere extends beyond the Earth. However, to date no experiment has been conducted to perform an extended duration, in-situ observation of the lunar atmosphere.  We have designed a small (10 × 10 × 10 cmand a mass of 1.3 Kg), multi-band imager that operates in the CCD-band (approximately, 450 – 900 nm). The instrument is easily tailored to meet a specific application by selecting the appropriate combination of interference filters. If such an instrument is placed on a lunar orbiting platform, it will generate a long-term database to study the morphology of the lunar atmosphere or surface features observable in this band.

The instrument has an angular resolution of 0.1and a field of view of 35× 25. This large field of view is shared by a mosaic of interference filters chosen for a specific application. The instrument uses a custom-designed computer program for automatic exposure control and communicates using standard serial and ethernet protocols.

This design has been validated using commercial off-the-shelf components for sodium and potassium resonance emissions at 589 nm and 770 nm, respectively.

How to cite: Chakrabarti, S., Mukherjee, S., Cook, T., and Baumgardner, J.: A customizable wide field-of-view multiband imager for lunar atmospheric Studies, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20425, https://doi.org/10.5194/egusphere-egu2020-20425, 2020.

D825 |
Alexander Grigoriev, Andrei Fedorov, and Nicolas André

An important technique of modern space plasma diagnostics is a detection and imaging of low energy (below 10 keV) energetic neutral atoms (ENA). Any space mission devoted to study of the planetary plasma environments, planetary magnetospheres and heliosphere boundaries, needs a low energy ENA imaging sensor in its payload list. A common approach to the ENA detection/imaging is to make energetic neutral atoms glance a high quality conductive surface and either produce a secondary electron, or produce a positive or negative reflection ion. In the first case we can collect and detect the yielded secondary electron and generate a start signal. The reflected neutral atom can be directed to another surface with a high secondary electron yield. Thus we can measure a time-of-flight of the reflected particle to get its velocity. In the second case we can analyze the reflected ion in an electrostatic analyzer to get the particle energy.

Many types of conversion surfaces have been investigated over last decades in order to optimize an ENA sensor properties. We investigated properties of a thin layer of graphene applied to a silicon wafer surface. The experimental setup consisted of a secondary electron detector, neutral/ions separator and a high resolution particle imager. We used an incident He beam with energy of 200 eV - 3000 eV. We obtained a secondary electron emission, particle reflection efficiency, scattering properties, and a positive ion production rate as a function of the incident beam energy and the grazing angle. The experiment results show that 1) Graphene is a good source of secondary electrons even for low energy incident particles; 2) ENA scatter from the graphene surface similar to other surface types; 3) Graphene does not convert incident ENA to positive ions, especially for high grazing angles.

How to cite: Grigoriev, A., Fedorov, A., and André, N.: Can we use graphene as a conversion surface for a neutral particle detector?, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9593, https://doi.org/10.5194/egusphere-egu2020-9593, 2020.