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We present the analysis of a 2.06 Ga apatite crystal obtained from an ultramafic phoscorite rock from the Phalaborwa Complex (Limpopo Province, South Africa) [1]. A space-prototype laser ablation ionisation mass spectrometer (LIMS) [2,3] was used to study the chemical composition of the sample. Mass spectra were recorded from a sample area of 0.6x0.6 mm2, with a spatial resolution of 30 μm and sub-micrometre depth resolution.Apatite is a calcium phosphate mineral expressed by the chemical stoichiometric formula [Ca5(PO4)3(F, Cl, OH)]. The halogen site, occupied by F, Cl, and OH, corresponds to an isomorpous series with fluor-, chlor- and hydroxyl-apatite end members, respectively. Apatite, being an accessory mineral in igneous and other rocks, commonly contains a range of other elements that do not fit well into the major rock forming minerals, such as rare earth elements (REE). These are suitable targets for investigating physical and chemical conditions in igneous rocks and the volatile evolution of magmas.The analysis of the spectra recorded with our LIMS system for the abundances of the elements of interest at each location were performed in two steps. First, the abundances of each element across the sampled area were compiled in element maps. And second, an unsupervised machine learning algorithm based on clustering and network analysis was applied to the data set of analysed mass spectra to separate it into groups of distinct chemical composition. Subsequently, a more detailed analysis was conducted on each of the recovered groups to assign the corresponding mineral. In addition to the group of spectra belonging to apatite, which was assigned to fluorapatite, other minerals were identified, amongst others olivine. This method yields an unsupervised approach to identify different mineralogical entities present within a sample. This network analysis method was previously applied to a 1.88 Ga Gunflint sample (Ontario, Canada) to separate spectra recorded from the host (chert) from spectra containing signatures of organic matter from fossilized microbes [4].Given that the data were recorded using a miniature mass spectrometer designed for space flight, this analysis demonstrates the analytical capabilities of our LIMS system that could be achieved in-situ on other planetary bodies in our Solar System, for example on the Moon or on Mars. The current performance of this miniature LIMS instrument to study the chemical composition of apatite is sufficiently high to measure volatiles (H, F, Cl) and nearly all relevant mineral and partially trace elements (Na, C, Mg, Si, S, K, Mn, Fe, Sr, Ba), including REE (La, Ce, Pr, Sm) which allows for a systematic quantitative analysis of their distribution.[1] Tulej, M. et al., 2022, https://doi.org/10.3390/universe8080410.[2] Riedo, A. et al., 2012, https://doi.org/10.1002/jms.3104.[3] Tulej, M. et al., 2021, https://doi.org/10.3390/app11062562.[4] Lukmanov, R.A. et al., 2022, https://doi.org/10.3389/frspt.2022.718943

The search for evidence of extant and extinct life on Mars is of big interest for future robotic and human exploration missions. The properties and characteristics of evaporites such as gypsum make them an easily accessible target in the search for biosignatures of extraterrestrial life. On Earth, a diverse microbial community inhabits gypsum in modern brines. These microbes are easily entombed within gypsum due to its fast precipitation. Studies of primary lower gypsum deposits, accumulated in the Mediterranean Basin during the Messinian salinity crisis (5.97 – 5.33 Ma), revealed a well-preserved and prominent archive of diverse microbial life. Similar archives might exist on Mars considering the desiccation of large bodies of water there, representing a promising target for exploring the possibility of life on Mars. The recent imaging mapping and analysis done by orbiters and rovers on the surface of Mars led to the discovery of abundant gypsum and evaporite minerals suggesting the evaporation of large lakes and lacustrine systems and as the surface of Mars dried out, hypersaline lakes would have filled the ancient lake system. A similar scenario happened on Earth when thick layers of gypsum were deposited during the Messinian salinity crisis when the Mediterranean was turned into the youngest salt giant in Earth’s history.Previous chemical and molecular laser mass spectrometry analyses done on microfossils preserved in different rock records showed these instruments’ ability to detect biosignatures related to ancient life. In this study, we successfully investigated the chemical composition of fossil filaments interpreted to be benthic microbial assemblages dominated by chemotrophic sulfide-oxidizing bacteria, sulfate-reducing bacteria, and planktonic cyanobacteria. This study demonstrated the efficiency of a miniaturized next-generation Laser based Mass Spectrometer (LMS) designed for future space explorations in the detection of microbial chemical biosignatures trapped in Messinian gypsum, shading light to the potential application to the search for life on Mars. Literature Natalicchio, M., Birgel, D., Dela Pierre, F., Ziegenbalg, S., Hoffmann-Sell, L., Gier, S., & Peckmann, J. (2022). Messinian bottom-grown selenitic gypsum: An archive of microbial life. Geobiology, 20, 3– 21. https://doi.org/10.1111/gbi.12464.Bayles, M., Belasco, B.C., Breda, A.J., Cahill, C.B., Da Silva, A.Z., Regan, M.J., Jr., Schlamp, N.K., Slagle, M.P. and Baxter, B.K. (2020). The Haloarchaea of Great Salt Lake as Models for Potential Extant Life on Mars. In Extremophiles as Astrobiological Models (eds J. Seckbach and H. Stan-Lotter). https://doi.org/10.1002/9781119593096.ch4.Lukmanov, RA., Tulej, M., Ligterink, NFW., et al. ( 2021). Chemical identification of microfossils from the 1.88-Ga Gunflint chert: Towards empirical biosignatures using laser ablation ionization mass spectrometer. Journal of Chemometrics, 35 ( 10):e3370. doi:10.1002/cem.3370.

Direct analysis of micrometer-scale features embedded in solid samples of a wide chemical variety is an integral part of many fields in geo-, geobio-, and planetary sciences. Examples range from microscopic mineral inclusions in meteoritic material, (e.g., zircons, CAIs, chondrules, etc.) to biological inclusions in a variety of mineralogical host materials, e.g., (putative) fossils of microbial species. In many of these use-cases, the determination of the element and/or isotope composition, specifically those of minor or trace abundance, is of prime interest, meaning mass spectrometry is typically the preferred analysis technique.As a result, a growing group of instruments has been (and are being) developed specifically with the purpose of element and/or isotope analysis of microscale features in solid hosts, each with its specific advantages and limitations. Perhaps the most well-known technique is (nano)SIMS, which boasts analysis spot sizes down to the nanometer level as well as ppm to ppb detection limits, but struggles with quantitativeness and capital and operating expenses. In the field of laser-based solid sampling mass spectrometric techniques, LA-ICP-MS has become a well-established technique, mainly due to its reproducibility and ease of operation. However, due to necessity to transport particles from the ablation plume to the ICP, this technique is inherently limited through fractionation effects and isobaric interferences with the plasma and carrier gas. Furthermore, sample dilution in the plasma and the subsequent loss of sample at the ICP-MS interface result in diminished limits of detection.Another member of the laser-based solid sampling techniques is Laser Ablation Ionization Mass Spectrometry (LIMS), in which the ions present in the ablation plume are directly introduced into the mass spectrometer. This direct sampling of the ablation plume results in both a significant advantage over LA-ICP-MS (high sensitivity) and a challenge (mass resolution). The limited mass resolution of typical LIMS instruments often makes (quantitative) analysis challenging due to isobaric interferences, especially when applied to more complex materials. To solve this issue, the Laser Mass Spectrometer – Gran Turismo (LMS-GT) was developed at the University of Bern with the aim of achieving mass resolutions sufficient to resolve the most common isobaric interferences (M/ΔM = 10.000).Over the last years, commissioning and continuous improvement of the instrument has been ongoing, which has led to a set of analytical performance characteristics which highlight the potential complementary value of LMS-GT. In this talk, we will discuss the latest technological developments1, latest analytical performance metrics (mass resolution, mass accuracy, limits of detection, etc.), and element and isotope ratio accuracies2,3. We will also discuss a case-study in which LMS-GT was used to study fossilized microbial inclusions in Gunflint chert4, highlighting both the potential strength and challenges for LMS-GT in a geo- and geobiosciences context.1. Gruchola, S. et al., Int. J. Mass Spectrom. 474, 116803 (2022).2. Wiesendanger, R. et al., J. Anal. At. Spectrom. 34, 2061–2073 (2019).3. de Koning, C. P. et al., Int. J. Mass Spectrom. 470, 116662 (2021).4. Lukmanov, R. A. et al., Front. Space Technol. 3, (2022).

Venus is the closest and most similar planet to Earth in the whole solar system, yet, basic measurements are missing. The atmospheric composition has been studied to some extent with the Pioneer Venus Orbiter mission and the more recent Venus Express, however, the concentration of many species and their isotopic ratios are not yet known with satisfying accuracy. Especially when it comes to the heavy noble gases as Kr and Xe, there is little to no collected data in this field. These elements form a key link to the reconstruction of the atmospheric evolution, which would deliver crucial information on the formation of Earth-like bodies. Knowing the abundances of the noble gases may allow us to answer the question why Venus did not evolve to a potentially habitable planet like its neighbour Earth. This paper presents a meta-study of existing observations of Venus' upper atmosphere and exosphere and an exospheric model of the thermal and hot atmosphere of Venus above the homopause. Mass spectra for possible future Venus missions are predicted, as for example the EnVision mission of ESA. The main focus are the heavy noble gases and requirements for the trajectories are proposed. In addition, mass spectra and recommended integration times for the Venus flyby of ESA's JUICE mission are derived.