22-EPN3-054: Searching for Biosignatures in Extreme Environments – High-Altitude Andean lakes as Mars analogues

Visit by Fernando J. Gomez of CICTERRA (Argentina) to TA2 Facility 29 – Nano Secondary Ion Mass Spectrometer (South Korea) and TA2 Facility 34 – Atomic Level Electronic Structure STEM (South Korea).
Dates of visit: 04-15 September 2023

Report Summary: Microbial activity leaves fingerprints in the sedimentary record. Through its metabolism microbes catalyse reactions, thus recycling minerals, dissolved chemical species and gases. This produces changes in the isotopic and trace elements ratios and changes in crystal mineral fabrics, that can be preserved in the sedimentary record. This signals of biological activity, when differentiated from abiotically controlled processes, are known as biosignatures., and are a part of the toolbox of geobiological and astrobiological research. The main question here is how can textural and chemical biogenic signatures be clearly differentiated from abiotically mediated processes? The study of ancient deposits is problematic, in that primary signatures have likely been modified through changes in the chemical environment during diagenetic processes. In contrast, the investigation of modern analogues, where processes can be studied in situ and where secondary alteration is incipient to absent, can help to differentiate between biotically and abiotically controlled signatures in the sedimentary record.

In this study we explored the chemical isotope signature within microbially-related sedimentary carbonates, including: stromatolites, oncoids/pisoids and thrombolites. We focused on carbon isotopes in different microtextures to recognise isotope signatures at the micro-nano-scale with the aim of recognising chemically versus biologically precipitated minerals and organic components.

22-EPN3-015: Trace Element Partitioning Between (Mg,Ca)S and Highly Reduced Magmas – Implications for the Volatile Budget and Thermal Evolution of Mercury

Visit by Laurie Llado and Yishen Zhang of the University of Liege (Belgium) to TA2 Facility 21 – OU NanoSIMS 50L (UK).
Dates of visit: 31 July – 18 August 2022

Report Summary: Mercury’s magma ocean is thought to have contained abundant dissolved sulfur, which would have formed sulfides once the magma ocean reached sulfide saturation. Due to the low concentrations of Fe²⁺ in the silicate portion of Mercury and S speciation at low fO₂, it is likely that crystallisation of the magma ocean produced minerals of the MgS-CaS solid solution. In this study, we aim at calculating the U, Th, and K trace element partitioning between (Mg,Ca)S sulfides and their equilibrium silicate melt to better understand the thermal evolution of Mercury.

To this end, the U, Th, and K trace element compositions of ultra-small (Mg,Ca)S crystals (3-15 μm) produced in experiments performed under highly reduced conditions were measured using the Open University NanoSIMS (UK). Preliminary results shows that U and Th partition coefficients of MgCaS crystals are lower than U and Th partition coefficients in CaS and FeS. Further investigation is required to confirm these preliminary results and to determine more accurately the U, Th and K partition coefficients. Nevertheless, the acquired U/Mg and Th/Mg ratios and theirs related partition coefficients will be used to provide comprehensive knowledge about the thermal evolution of Mercury.

20-EPN2-114: Microbial Adaptation in the Hypersaline Environment of Sua Pan Evaporator Ponds in Botswana and Implications for Search for Life on Mars (Part 2 – Microbial Characterisation)

Visit by Claudia Pacelli of the Italian Space Agency (ASI) to TA2.19 Center for Microbial Life Detection, Medical University Graz (Austria).
Dates of visit: 06-10 November 2023

Report Summary: The search for life on other planets, first of all Mars, is necessary informed by terrestrial biology. Studies of microorganisms on Earth expanded the limits of life to such an extent that many environments on Earth, previously thought to be uninhabitable, were found to harbor life. Some of these environments overlap with extraterrestrial planetary environments in some physical and chemical conditions. Because they contain life on Earth, similar environments can sustain life elsewhere in the Universe.

On Earth, the distribution of hypersaline environment is largely reported and mainly in arid environments like deserts. Among them, the Makgadikgadi salt pans (which include the Nxai, Ntwetwe and Sua pans), located in north central Botswana are considered one of the largest in the world, where the salts concentration is up to 21% of NaCl. These conditions may be compared with those detected on Mars.

This Europlanet project will provide valuable information about the limit of life on Earth, identifying the habitable environment for microorganisms in Makgadikgadi Salt Pans similar to the evaporitic basins or playa described in different areas of the Martian surface, such as Arabia Terrae and Meridiani Planum. In addition, metagenomics results allow us to investigate the genomic traits involved in microbial adaptation to extreme conditions on Earth, which have implications for the prospect of life on other planets since it is possible that life as behaves as it happened in the Salt Pans on Earth. These data will expand our knowledge about the habitability of Mars and will support future robotic and Mars sample return missions.

22-EPN3-036: Investigating Titanium and Chromium Isotopes in Unusual Achondrite NWA 8564

Visit by Julia Cartwright of University of Alabama (USA) to TA2.14 ETH Zurich Geo- and Cosmochemistry Isotope Facility (Switzerland).
Dates of visit: 10-22 July 2023

Report Summary: We pursued high-precision chromium (Cr) and titanium (Ti) isotopic analysis to better refine the parent body of little-studied unusual achondrite Northwest Africa (NWA) 8564. While originally classified as a cumulate eucrite, NWA 8564 displayed unusual lead (Pb) data, suggestive of contributions from an exotic component, thus calling into question its assumed parent body, asteroid 4-Vesta. In this work, we sampled, prepared, and dissolved materials from NWA 8564, eucrites Juvinas and Tirhert, alongside diogenite NWA 7831 and a terrestrial standard to determine the parentage of NWA 8564.

Samples were selected, sampled and sent to ETHZ to be crushed and taken through dissolution and column chemistry. As Cr and Ti isotope analysis require different schedules, the chemistry and analysis stages were staggered for efficiency (e.g., three Ti columns and the first stages of Cr column cleaning were performed prior to Ti arrival). During the visit, the Cr separation procedure was carried out and preliminary analyses were performed after the visit. Eluted Ti aliquots were assessed for content and subsequently diluted for MC-ICP-MS analysis in week 1. Following data assessment/reduction, further aliquots were prepared through week 2, resulting in ~4 sessions of Ti data. The preliminary results show Ti and Cr isotope values for NWA 8564 within the range of eucrites. This suggests that NWA 8564 originates from Vesta, and must have experienced a significant event on Vesta that affected the Pb isotope data. This may include remelting associated with a large impact, potentially linked to the large, ancient basins at Vesta’s south pole.

22-EPN3-059: Electron Impact Induced Emission of Formamide – Excitation Processes Study

Visit by Frantisek Krcma, Brno University of Technology (Czechia), to TA2 Facility 13 – Electron Induced Fluorescence Laboratory (Slovakia).
Dates of visit: 06-15 November 2023

Report summary: The main goals of the 2023 visit were to study the electron impact emission cross sections, spectral features, and dissociation thresholds of formamide (CH₃NO) vapour. The expected products of CH₃NO – atomic hydrogen, CO, CN, CH, NH. The present experiments are part of a campaign to understand diagnostic electron-impact driven emission and ionisation of molecules present in astrophysical environments.

During the visit we first determined the experimental conditions especially the suitable range of molecular beam pressures low enough to ensure binary collisions with electrons but high enough to ensure reasonable signal-to-noise ratio. Then we performed spectral measurements at various wavelength regions and identified the basic spectral features. It was unusually difficult to determine
suitable experimental conditions due to unstable formamide vapour pressure in the system. During the visit we had to slightly modify the gas inlet system of the apparatus. Therefore, further experimental measurements will be performed later in cooperation with the Comenius University group.

22-EPN3-035: Survival of chondrites in humid climate (Germany & Europe)

Visit by Silke Merchel of University of Vienna (Austria) to TA2 Facility 16 – Carbon-14 Dating AMS Laboratory (Hungary).
Dates of visit: 03-09 June 2023.

Report Summary: The extraction of carbon from stony and iron meteorites for ¹⁴C/¹²C accelerator mass spectrometry was tested using a commercial LECO inductive furnace apparatus.

Extraction conditions and chemicals such as gases, fluxes (iron, titanium) were investigated for their influence on blank levels, cross-contamination and quantitative extraction. Further systematic investigations are still needed to find the ideal extraction conditions. Additionally, off-line, CO₂ cleaning from SOx seems to be mandatory for reliable results. Test measurements with the gas ion source of the 50 kV LEA system, are promising to overcome “dead” carbon addition to carbon released from 50-100 mg meteorite.

22-EPN3-027: Dust-Carbon-Climate Feedbacks Tested Through Detailed Independent Dating of Arctic Wind-Blown Dust Sequences on Greenland (Part 2 – Laboratory Analyses)

Visit by Thomas Stevens of Uppsala University (Sweden) to TA2 Facility 16 – Carbon-14 Dating AMS Laboratory (Hungary).
Dates of visit: 04 – 13 March 2023.

Report Summary: Over a 10 day visit to the TA facility a total of 67 (45 macrofossils and 22 bulk sediment samples) radiocarbon ages were obtained from loess samples taken around Kangerlussuaq in western Greenland. This represents the largest dataset on such sediments in Greenland, and complements our existing luminescence and radiocarbon analyses on similar or duplicate samples. The aim of the work is to develop reliable independent age models for loess accumulation in Greenland, and thereby allow analysis of past climate, permafrost and dust over the last c. 6-7 thousand years. In particular, our aim was to test the cause of the offsets between luminescence and radiocarbon dating uncovered in our previous work, which represents a significant obstacle to developing age models for Greenlandic loess.

The new data represent a significant step towards resolving this. A first outcome is that macrofossil dating in these sediments seems extremely problematic, with most yielding post bomb ages indicating significant modern carbon contamination. A second outcome is that the high and low temperature bulk carbon dating shows more promise, and reveals extremely young ages (last 150 yrs to post bomb) for the upper c. 15-20 cm of sediment in the profiles. This is reinforced by the luminescence data, and suggest extremely rapid recent accumulation and high dust storm activity in the region. Finally, we will use the new ages to derive robust age models for past climate reconstructions in west Greenland, an area currently undergoing rapid climate change.

20-EPN2-031: Determination of the Timing of the Final Deglaciation and the Depth of Subglacial Erosion Using In-Situ Produced Cosmogenic ¹⁴C in Combination with Existing Cosmogenic ¹⁰Be Data

Visit by Régis Braucher of Cerege CNRS-Aix-Marseille University (France) to TA2 Facility 16 – Carbon-14 Dating AMS Laboratory (Hungary).
Dates of visit: 12 – 16 December 2022.

Report Summary: Glacial landforms formed during the last deglaciation in several valleys of the Retezat Mts (Southern Carpathians) have been dated by in situ produced cosmogenic ¹⁰Be. A bias towards old exposure ages has hindered the age determination of the last deglaciation phases (Ruszkiczay-Rüdiger et al., 2021, Geomorphology, 107719).

The measurement of the concentrations of the short-lived in situ produced ¹⁴C concentrations in the framework of the TA visit enables us to estimate the true age of these landforms and also allows the quantification of the amount of inherited ¹⁰Be. This inherited nuclide inventory is used to estimate the depth of subglacial erosion during the last glacial phase, a parameter that was not yet quantified in the region yet. Sixteen quartz samples (mass: 4-5 g) were analysed in the framework of this project in the Isotoptech AMS Laboratory (Debrecen, HU). All samples gave a reliable C yield (between 40-10 ug/sample). A special Gas ion source interface (GIS) and accelerator mass spectrometer (AMS) coupling technique enabled us to quantify the ¹⁴C/¹²C ratio in the small sized CO₂ samples. AMS ¹⁴C sample preparation and analyses was controlled by reference material preparations and parallel analyses. The resulted ¹⁴C data (fractionModern) now can be used for a more realistic exposure age determination and estimation of the depth of subglacial erosion in the Retezat Mts. This is the first application of the ¹⁰Be-¹⁴C nuclide pair in Eastern Central Europe.

22-EPN3-110: Clumped Isotope Thermometry of Travertines in the Tauern Window (European Alps) – Significance for Past Seismicity and Risk Assessment of the Brenner Base Tunnel

Visit by Diethard Sanders of the University of Innsbruck (Austria), to TA2 Facility 17 – Isotoptech Stable/Clumped Isotopes Laboratory (Hungary).
Dates of visit: 06-10 November 2023.

Report summary: In the European Eastern Alps, travertines precipitated from springs with superambient temperature are very rare. Travertines show fabrics distinct from ambient-temperature
spring limestones. We had identified three fossil travertine deposits in the Navis Valley, a valley between 1005 m a.s.l. (debouch) and a watershed at ~2300–2600 m a.s.l. The travertines are located at different altitudes (1816 m, 1706 m, 1228 m), and consist of stacked laminae 1.5–4 mm thick of radial-fibrous calcite. In active travertines, such fabrics characterise crystallisation at ~15-25°C. The Navis fossil travertines post-date the Last Glacial Maximum, as shown by four U/Th ages between 10.95 ± 0.08 to 9.94 ± 0.09 ka BP 1950 AD.

Clumped isotope thermometry (Δ47-thermometry) indicates that the travertine of each location precipitated at superambient temperatures well-above the mean annual air temperature in the recharge area. The travertine-depositing waters probably rose along a steep-dipping fault system in the rock substrate, whereby the activation of these faults may have been related to seismic activity. In the subsurface of the study area, faults associated with highly mineralised warm waters were encountered also in excavation of the Brenner Base Tunnel. Our results provide the first quantitative approach with respect to formation temperature and numerical age to the rare travertine deposits of the Eastern Alps, and may alert geologists to identify this specific type of deposit as a ‘warning hint’ for potential episodes of active faulting. This is relevant to seismic hazard assessment of buildings such as the Brenner Base Tunnel.

Read the full scientific report, with kind permission from Simone Silvestro.

20-EPN2-095: Carbon Isotopic Fractionation and Quantification in Perennial Cave Ice

Visit by Artur Ionescu of the Babes-Bolyai University (Romania), to TA2 Facility 17 – Isotoptech Stable/Clumped Isotopes Laboratory (Hungary).
Dates of visit: 27 November – 08 December 2023.

Report Summary: The aim of this project is to investigate the carbon isotopic variation in perennial cave ice in different phases, for the determination of fractionation processes and estimation of the carbon source (organic or inorganic). To do so, we aim of using two types of samples, the first from
extracted ice from perennial cave glacier and ice created in laboratory conditions. We measured δ¹³C in gases trapped as “bubbles” in the ice mainly CO₂, in dissolved carbon in the ice as HCO₃ and CO₃, and in the cryogenic cave carbonates.

Our hypothesis presumes that isotopic fractionation of carbon could shift an inorganic
signature towards a more organic one, thus making it difficult to assess the origin of carbon,
hence misinterpreting the origin.

In total 36 measurements have been performed on carbon-13. Our preliminary data on the
fractionation of carbon-13 show that during freezing the bubbles “concentrate” the light
isotopic ratios while the most enriched values were found in the cave carbonates. Thus
confirming our hypothesis. This is the first study that described isotopic values of carbon-13
in the different phases of the cave ice, however more laboratory experiments are needed to
better constrain the isotopic fractionation process.

22-EPN3-098: VNIR Analyses on Mars Analogues Volcanic Products at Low Temperature – Investigating the Influence of Granulometry and Crystallinity

Visit by Maximiliano Fastelli and Marco Baroni of the University of Perugia (Italy) to TA2.8 CSS (Cold Surfaces Spectroscopy) at IPAG (France).
Dates of visit: 22 April – 03 May 2024

Report Summary: During this project funded through the Europlanet 2024 RI 3rd call, reflectance VIS-NIR spectra were collected at the CSS laboratory in Grenoble, France. Different temperatures were chosen to collect reflectance spectral data of 2 synthetic martian rocks analogues which were collected in the 1 – 4.8 μm range considering 3 different crystal-to-glass ratios and 3 different grain
sizes.

We synthesised two magmatic melts having chemical compositions relatable to Gusev and Gale crater, on Mars. For each composition, one glass and two samples with different crystallisation degrees were analysed. Moreover, the spectra of three different grain size ranges (30-75 μm; 75-106 μm;106-150 μm) for each composition were collected.

The different degrees of crystallisation affect first the type of identified absorption feature and secondly the slope of reflectance spectra with important and interesting changes. Increasing crystallinity causes slopes of spectra to gradually shift from positive for glasses towards flat-negative for crystalline material. On the other hand, grain size influences reflectance intensity and slope, as increasing grain size results in lower reflectance values and flatter slopes. No loss of characteristic spectral is observed with changing grain size.

These results provide further information on the spectral response of synthesised rock samples, especially for what concerns glass-bearing materials, that can be used for modelling of spectral information coming from rocky bodies in the Solar system, especially for Mars. The relationships that will be observed could be used by the European and international scientific community, to interpret spectra obtained by remote sensing and field investigations of volcanic terrains on rocky bodies in terms of i) rock composition, ii) magmatic evolution, iii) rheological properties/cooling rates of magmas and iv) possible geodynamic source.

22-EPN3-080: Chronology, Evolution of CAIs in Ordinary Chondrites

Visit by Francois Holtz of Leibniz University of Hanover (Germany) to TA2.9 Ion Probe Facility (IPF), CRPG (France)
Dates of visit: 02-09 February 2024

Report Summary: This study investigates naturally quenched and experimentally homogenised olivine-hosted melt inclusions (OLHMIs) from different geodynamic settings. Using SIMS analysis at CRPG, Nancy, we measured H₂O and CO₂ contents of OLHMIs from Loihi Seamount, Etna, and Klyuchevskoy volcanoes. Values were adjusted using natural and synthetic glass references to account for compositional effects. OLHMIs from Loihi seamount pillow lavas showed H₂O contents comparable to published data. Experimental heating led to significant H₂O loss over time, with near-complete loss after 5 hours. Additionally, we analysed OLHMIs from Etna volcano for Br contents, adjusting with calibration from low-Br Macquarie MORB glasses and high-Br synthetic basaltic glasses. Br analysis exhibited a linear calibration with high accuracy. OLHMIs from etnean FS tephra had relatively low Br contents, with a slightly elevated Br/Cl ratio compared to mantle values. These findings contribute to our understanding of volatile behaviour in magmatic systems and offer insights into volcanic processes.

22-EPN2-036: Chronology, Evolution of CAIs in Ordinary Chondrites

Visit by Ritesh Kumar Mishra of the Veer Kunwar Singh University, Ara, Bihar (India) to TA2.9 Ion Probe Facility (IPF), CRPG (France)
Dates of visit: 13-17 November 2023

Report Summary: The first forming Solar System solids are the refractory oxides and silicates of calcium, aluminium, titanium and magnesium which give them their eponymous name Calcium, Aluminium-rich Inclusions (CAIs). Only a few (~50), mostly very small (~20-50 microns) have been found in Ordinary chondrites. Our extensive search for large CAIs in ordinary chondrites resulted in finding about 10 CAIs in Semarkona (LL3.00), ALHA81251 (LL3.3), Chainpur (LL3.4). Three Oxygen isotopic (Δ¹⁷O) studies along with ²⁶Al-²⁶Mg short-lived now extinct chronology were carried in 4 CAIs and 2 Al-rich chondrules to decipher their genesis and provenance and make comparative analysis with the vast amount of previous data from the carbonaceous chondrites.

22-EPN3-047: Vein networks in the Variscan foreland basins in western Europe

Visit by Jeroen van der Lubbe of the Vrije Universiteit (Netherlands) to TA2.9 Ion Probe Facility (IPF), CRPG (France)
Dates of visit: 13-17 November 2023

Report Summary: The primary objective of the proposed research is to investigate the mechanisms of fluid and trace metal transportation from the deeper orogen to the mid-upper crustal levels. These levels are particularly significant as they are known to host mineralisation, including metals that play a crucial role in facilitating the energy transition. In this research, an examination is conducted on samples of quartz veins originating from the High Ardennes Slate Belt in the Rursee region of Germany, as well as its equivalent in Almograve, Portugal. The objective is to establish limitations on the movement of fluids and elements within upper crustal settings. The presence of veins in our research among allochthonous terranes with a peri-Gondwanan affinity provides support for the hypothesis that these veins may have originated from the same sources during the Variscan orogeny.

This research is a component of the ITN FluidNET initiative, which seeks to comprehend the fluid mobility and elemental transport across various levels of the Earth’s crust, including the lower, middle, and upper sections. The current investigation is done on context of the doctoral study of Akbar Huseynov, who focusses on the fluid migration and vein formation in the upper crust. The FluidNET project aims to validate its overarching hypotheses by employing various isotopic techniques involving radiogenic and stable isotopes, examining trace element distributions within fluid inclusions, and conducting geochronological analysis of fluid inclusions. These methods enable the project to trace the migration of fluids across a range of scales, from nano- to kilometres. The primary objective of this study is to enhance our understanding about the transport fluxes of metals that are crucial to current energy transition. To do this, the research aims to integrate fluid transport across temporal and spatial dimensions via the use of analytical and numerical methodologies.

20-EPN2-068: Primitive Space Materials (PriSMa)

Visit by Chrysa Avdellidou of the Observatoire de la Cote d’Azur (France) to TA2.7 Light Gas Gun Laboratory, University of Kent (UK)
Dates of visit: 17-21 April 2023

Report summary: Simulants of surface materials for various small bodies were sourced, characterised and formed into blocks. These blocks were sent to the University of Kent and used as targets in their two-stage light gas gun. An extensive programme of 20 shots was carried out at speeds from 0.39 to 4.9 km/s. This covers a range from low speed impacts up to the mean speed of impacts in the asteroid belt (5 km/s). All targets were weighed and imaged before each shot. Post-shot, the resulting impact craters were all been imaged, and crater size and shape have been measured. Crater ejecta was also collected. More detailed analysis is underway. With the results so far, it is now possible to predict crater shape in the strength regime over a wide speed range for such bodies and estimate the volume of ejected material. This experimental campaign included novel impact experiments to study the contamination of primitive bodies surfaces by foreign material.

This programme was successful and is being used to interpret remote sensing data from previous and upcoming space missions, such as OSIRIS-REx and MMX.

22-EPN3-043: Investigating Reflectance and Emissivity Spectra of Minerals and Analogs under Vacuum to Support Analyses of Lunar Spectra

Visit by Janice Bishop of the SETI Institute (USA) and Kierra Wilk of Brown University (USA) to TA2 Facility 5 – DLR Planetary Spectroscopy Laboratory (Germany).
Dates of visit: 12-21 November 2023

Report Summary: Laboratory experiments were conducted to investigate H₂O and OH species in minerals under different environmental conditions in order to improve our understanding of hydrated
species (H₂O/OH) identified on the Moon through both the H₂O stretching bands near 3 μm and the H₂O bending vibrations near 6 μm.

We were able to run reflectance and emission spectra under vacuum and different temperatures at the DLR Planetary Spectroscopy Laboratory (PSL) for several lunar analogues, plus a couple of sulfate analogues for Mars and an ammonia clay analog for Ceres. Measuring both the 3 μm and 6 μm spectral features with the same instrument under the same conditions was very helpful for our lunar project because these have been characterised using different instruments under different conditions at the Moon.

The hydration features near 2.7-3 μm are observed in the Moon Mineralogy Mapper (M3) hyperspectral imaging data on board the Chandrayaan-1 orbiter and exhibit variations near 2.7 and 2.9 μm that could be consistent with changes in hydroxyl (OH) and molecular H2O species in the lunar regolith. The band observed near 6 μm in telescopic spectra of the Moon are only due to H₂O species and not to OH. We observed changes with increasing vacuum level and increasing temperature for both features at 3 and 6 μm for our lunar samples. We also observed changes in the Mars and Ceres analogs under vacuum and after heating. Obtaining these spectral measurements at the DLR-PSL provided essential data for our planetary science projects.

20-EPN2-021: Construction of lunar mineral maps using NIR hyperspectral data in combination with GRS and/or LIBS data

Visit by Kyeong Ja Kim of the Korea Institute of Geoscience and Mineral Resources (Korea) to TA2 Facility 5 – DLR Planetary Spectroscopy Laboratory (Germany).
Dates of visit: 16-27 October 2023

Report Summary: There were three objectives of the project:

1. Development of a Bayesian method for spectral unmixing of NIR hyperspectral image data acquired by the Moon Mineralogy Mapper (M³) instrument with Gamma Ray Spectrometer (GRS) and Laser Induced Breakdown Spectroscopy (LIBS) data
2. Construction of global and regional maps of the main minerals of the Moon which are constrained by the elemental abundances measured by GRS and/or LIBS
3. Ingestion of the obtained map product into a mobile Geographic Information System (GIS).

Objective (1) was investigated with spectral analysis of various terrestrial analog samples along with lunar simulants to characterise image data that respond to mineralogical features which are directly connected to the mineralogical features of the moon investigated by remote sensing spectral data, especially M³ by Chandrayaan-1. The data obtained at DLR will be characterised with M³ data to understand mineralogical features as well as data obtained from KPLO GRS (KGRS). This approach will
guide in understanding regional mineralogical identification and elemental information that guides in investigation of lunar geology and resource prospecting. Objective (2) has been investigated using global elemental maps derived from M3 and Lunar Prospector GRS data.

The mineral maps constructed so far can be updated once KGRS data become available. Objective (3) will be addressed shortly by importing the constructed mineral maps into the K-Mapper software running on mobile devices. This will be invaluable for future human missions and the lunar resources prospecting international campaign as part of the Artemis 3+ activities.

22-EPN3-118: Irradiation of Enceladus Ice Analogues by Simulating Saturn’s Plasma Environment

Visit by Grace Richards of the Open University (UK) to to TA2.12 Atomki-Queen’s University Ice Laboratory for Astrochemistry (Hungary).
Dates of visit: 19-24 April 2023

Report Summary: Enceladus orbits within Saturn’s magnetosphere, which contains cold plasma composed of water group ions such as O⁺, OH⁺, and H₂O⁺. Irradiation of Enceladus’ surface by this plasma can change the volatile composition of the ice.

This program of experiments aimed to characterise the extent to which the Enceladus surface material is weathered by Saturn’s radiation environment, by exposing ice analogues to the ECR ion source in the AQUILA ice chamber. Ices, composed of H₂O, CO₂, NH₃, and CH₄, and with a temperature of 70K, were irradiated using relevant water group ions of energies between 10 – 45 keV. They were monitored throughout the irradiation process using FTIR spectroscopy and Quadrupole Mass Spectrometry (QMS). Temperature Programmed Desorption (TPD) studies were also carried out to investigate the radiation products in the ices.

20-EPN3-012: Probing Microscopic Mechanisms Behind Ice Processing by Cosmic Rays

Visit by Alexei Ivlev of Max Planck Institute for Extraterrestrial Physics (MPE) (Germany) to TA2.11 Atomki Ice Chamber for Astrophysics / Astrochemistry (ICA) (Hungary).
Dates of visit: 03-08 April 2024

Report Summary: The principal aim of the proposal was to conduct experimental studies of microscopic mechanisms controlling processing of astrophysical ices due to their bombardment by CRs. Specifically, based on indications obtained during our previous TA visit, we performed dedicated experiments on CO ices bombarded by protons with energies near and higher the electronic stopping power peak. The aim
was to investigate the scaling dependencies of the first radiolysis products with the stopping power,
and to compare those with the dependencies expected from existing radiolysis theories. We focused on studying accumulation of the first radiolysis products, such as C₂O, CO₂, C₃O, and C₃O₂, at low proton fluences, where they show a linear growth.

The measured results exhibit an excellent scaling with the stopping power, which unambiguously indicates that the previously assumed radiolysis mechanisms, assuming transport of radiolysis products in ice, cannot operate in our case. Instead, our results suggest that reactions in ice occur in situ, and are caused by a combination of secondary ionization and excitation processes triggered in ice by the ejected electrons. Ab initio studies of chemical reactions between CO and ionized or electronically excited C₃O₂ molecules will be carried out in order to identify possible routes of in situ C₃O formation.