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1. Astrobiological Potential of Rocks Acquired by the Perseverance Rover at a Sedimentary Fan Front in Jezero Crater, Mars

Author

T. Bosak, D. L. Shuster, E. L. Scheller, S. Siljeström, M. J. Zawaski, L. Mandon, J. I. Simon, B. P. Weiss, K. M. Stack, E. N. Mansbach, A. H. Treiman, K. C. Benison, A. J. Brown, A. D. Czaja, K. A. Farley, E. M. Hausrath, K. Hickman‐Lewis, C. D. K. Herd, J. R. Johnson, L. E. Mayhew, M. E. Minitti, K. H. Williford, B. V. Wogsland, M.‐P. Zorzano, A. C. Allwood, H. E. F. Amundsen, J. F. Bell III, K. Benzerara, S. Bernard, O. Beyssac, D. K. Buckner, M. Cable, F. Calef III, G. Caravaca, D. C. Catling, E. Clavé, E. Cloutis, B. A. Cohen, A. Cousin, E. Dehouck, A. G. Fairén, D. T. Flannery, T. Fornaro, O. Forni, T. Fouchet, E. Gibbons, F. Gomez Gomez, S. Gupta, K. P. Hand, J. A. Hurowitz, H. Kalucha, D. A. K. Pedersen, G. Lopes‐Reyes, J. N. Maki, S. Maurice, J. I. Nuñez, N. Randazzo, J. W. Rice Jr., C. Royer, M. A. Sephton, S. Sharma, A. Steele, C. D. Tate, K. Uckert, A. Udry, R. C. Wiens, and A. Williams

Subjects
Mars, sedimentary geochemistry, planetary geochemistry, origin of life, hydrothermal systems and weathering on other planets, hydrology and fluvial processes, Geology, QE1-996.5, Geophysics. Cosmic physics, QC801-809
Abstract

Abstract The Perseverance rover has collected seven oriented samples of sedimentary rocks, all likely older than the oldest signs of widespread life on Earth, at the exposed base of the western fan in Jezero crater, Mars. The samples include a sulfate‐ and clay‐bearing mudstone and sandstone, a fluvial sandstone from a stratigraphically low position at the fan front, and a carbonate‐bearing sandstone deposited above the sulfate‐bearing strata. All samples contain aqueously precipitated materials and most or all were aqueously deposited. Although the rover instruments have not confidently detected organic matter in the rocks from the fan front, the much more sensitive terrestrial instruments will still be able to search for remnants of prebiotic chemistries and past life, and study Mars's past habitability in the samples returned to Earth. The hydrated, sulfate‐bearing mudstone has the highest potential to preserve organic matter and biosignatures, whereas the carbonate‐bearing sandstones can be used to constrain when and for how long Jezero crater contained liquid water. Returned sample science analyses of sulfate, carbonate, clay, phosphate and igneous minerals as well as trace metals and volatiles that are present in the samples acquired at the fan front would provide transformative insights into past habitable environments on Mars, the evolution of its magnetic field, atmosphere and climate and the past and present cycling of atmospheric and crustal water, sulfur and carbon.

Published
2024
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3. An olivine cumulate outcrop on the floor of Jezero crater, Mars

Author

Y. Liu, M. M. Tice, M. E. Schmidt, A. H. Treiman, T. V. Kizovski, J. A. Hurowitz, A. C. Allwood, J. Henneke, D. A. K. Pedersen, S. J. VanBommel, Michael W. M. Jones, A L Knight, B. J. Orenstein, B. C. Clark, W. T. Elam, C. M. Heirwegh, T. Barber, L. W. Beegle, K. Benzerara, S Bernard, O. Beyssac, Tanya Bosak, A. J. Brown, E. L. Cardarelli, D. C. Catling, J. R. Christian, E. A. Cloutis, B. A. Cohen, S. Davidoff, A. G. Fairén, K. A. Farley, D. T. Flannery, A. Galvin, J. P. Grotzinger, S. Gupta, James Hall, C. D. K. Herd, K. Hickman-lewis, R. P. Hodyss, B. H. N. Horgan, J. R. Johnson, John Leif Jørgensen, L. C. Kah, J. N. Maki, L. Mandon, N. Mangold, F. M. McCubbin, S. M. McLennan, K. Moore, M. Nachon, P. Nemere, L. D. Nothdurft, J. I. Núñez, Lauren O'Neil, C. M. Quantin-Nataf, V. Sautter, D. L Shuster, K. L. Siebach, J. I. Simon, K. P. Sinclair, K. M. Stack, A. Steele, J. D. Tarnas, N. J. Tosca, K. Uckert, A. Udry, L. A. Wade, B. P. Weiss, R. C. Wiens, K. H. Williford, and M.-P. Zorzano

Subjects
Lunar And Planetary Science And Exploration
Abstract

The geological units on the floor of Jezero crater, Mars, are part of a wider regional stratigraphy of olivine-rich rocks, which extends well beyond the crater. We investigate the petrology of olivine and carbonate-bearing rocks of the Séítah formation in the floor of Jezero. Using multispectral images and x-ray fluorescence data, acquired by the Perseverance rover, we performed a petrographic analysis of the Bastide and Brac outcrops within this unit. We find that these outcrops are composed of igneous rock, moderately altered by aqueous fluid. The igneous rocks are mainly made of coarse-grained olivine, similar to some Martian meteorites. We interpret them as an olivine cumulate, formed by settling and enrichment of olivine through multi-stage cooling of a thick magma body.

Published
2022
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4. A Komatiite Succession as an analog for the Olivine Bearing Rocks at Jezero

Author

A., Brown, R.C., Wiens, S., Maurice, K., Uckert, M., Tice, D. Flannery R.G., Deen, A.H., Treiman, K. L., Siebach, L.W., Beegle, W.J., Abbey, J.F., Bell, L.E., Mayhew, J.I., Simon, O., Beyssac, P.A., Willis, R., Bhartia, R.J., Smith, T., Fouchet, C., Quantin-Nataf., Pinet, P.C., L., Mandon, S. Le, Mouélic, A., Udry, B., Horgan, F., Calef, E., Cloutis, N., Turenne, C., Royer, M.-P., Zorzano, E., Ravanis, S., Fagents, A., Fairen, S., Gupta, V., Sautter, Y., Liu, M., Schmidt, K., Hickman-Lewis, Tennessee State University, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Jackson School of Geosciences (JSG), University of Texas at Austin [Austin], Rice University [Houston], NASA Johnson Space Center (JSC), NASA, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Cornell University [New York], Imperial College London, Brock University [Canada], The Natural History Museum [London] (NHM), and pinet, patrick

Subjects
[SDU] Sciences of the Universe [physics], [SDU]Sciences of the Universe [physics], [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, planetary surface, mars, mineralogy, petrology
Abstract

International audience

Published
2022

5. WEBT multiwavelength monitoring and XMM-Newton observations of BL Lacertae in 2007-2008. Unveiling different emission components

Author

C. M. Raiteri, M. Villata, A. Capetti, M. F. Aller, U. Bach, P. Calcidese, M. A. Gurwell, V. M. Larionov, J. Ohlert, K. Nilsson, A. Strigachev, I. Agudo, H. D. Aller, R. Bachev, E. Benítez, A. Berdyugin, M. Böttcher, C. S. Buemi, S. Buttiglione, D. Carosati, P. Charlot, W. P. Chen, D. Dultzin, E. Forné, L. Fuhrmann, J. L. Gómez, A. C. Gupta, J. Heidt, D. Hiriart, W.-S. Hsiao, M. Jelínek, S. G. Jorstad, G. N. Kimeridze, T. S. Konstantinova, E. N. Kopatskaya, A. Kostov, O. M. Kurtanidze, A. Lähteenmäki, L. Lanteri, L. V. Larionova, P. Leto, G. Latev, J.-F. Le Campion, C.-U. Lee, R. Ligustri, E. Lindfors, A. P. Marscher, B. Mihov, M. G. Nikolashvili, Y. Nikolov, E. Ovcharov, D. Principe, T. Pursimo, B. Ragozzine, R. M. Robb, J. A. Ros, A. C. Sadun, R. Sagar, E. Semkov, L. A. Sigua, R. L. Smart, M. Sorcia, L. O. Takalo, M. Tornikoski, C. Trigilio, K. Uckert, G. Umana, A. Valcheva, A. Volvach, INAF - Osservatorio Astrofisico di Torino (OATo), Istituto Nazionale di Astrofisica (INAF), Instituto de Neurociencias de Alicante, Universidad Miguel Hernández [Elche] (UMH), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), and Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Brightness, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Power law, Spectral line, Luminosity, law.invention, Telescope, law, 0103 physical sciences, Blazar, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Line-of-sight, 010308 nuclear & particles physics, Molecular cloud, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astronomy and Astrophysics, Space and Planetary Science, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

In 2007-2008 we carried out a new multiwavelength campaign of the Whole Earth Blazar Telescope (WEBT) on BL Lacertae, involving three pointings by the XMM-Newton satellite, to study its emission properties. The source was monitored in the optical-to-radio bands by 37 telescopes. The brightness level was relatively low. Some episodes of very fast variability were detected in the optical bands. The X-ray spectra are well fitted by a power law with photon index of about 2 and photoelectric absorption exceeding the Galactic value. However, when taking into account the presence of a molecular cloud on the line of sight, the data are best fitted by a double power law, implying a concave X-ray spectrum. The spectral energy distributions (SEDs) built with simultaneous radio-to-X-ray data at the epochs of the XMM-Newton observations suggest that the peak of the synchrotron emission lies in the near-IR band, and show a prominent UV excess, besides a slight soft-X-ray excess. A comparison with the SEDs corresponding to previous observations with X-ray satellites shows that the X-ray spectrum is extremely variable. We ascribe the UV excess to thermal emission from the accretion disc, and the other broad-band spectral features to the presence of two synchrotron components, with their related SSC emission. We fit the thermal emission with a black body law and the non-thermal components by means of a helical jet model. The fit indicates a disc temperature greater than 20000 K and a luminosity greater than 6 x 10^44 erg/s., 11 pages, 7 figures, accepted for publication in A&A

Published
2009

6. Multifrequency monitoring of the blazar 0716+714 during the GASP-WEBT-AGILE campaign of 2007

Author

M. Villata, C. M. Raiteri, V. M. Larionov, O. M. Kurtanidze, K. Nilsson, M. F. Aller, M. Tornikoski, A. Volvach, H. D. Aller, A. A. Arkharov, U. Bach, P. Beltrame, G. Bhatta, C. S. Buemi, M. Böttcher, P. Calcidese, D. Carosati, A. J. Castro-Tirado, D. Da Rio, A. Di Paola, M. Dolci, E. Forné, A. Frasca, V. A. Hagen-Thorn, J. Heidt, D. Hiriart, M. Jelínek, G. N. Kimeridze, T. S. Konstantinova, E. N. Kopatskaya, L. Lanteri, P. Leto, R. Ligustri, E. Lindfors, A. Lähteenmäki, E. Marilli, E. Nieppola, M. G. Nikolashvili, M. Pasanen, B. Ragozzine, J. A. Ros, L. A. Sigua, R. L. Smart, M. Sorcia, L. O. Takalo, M. Tavani, C. Trigilio, R. Turchetti, K. Uckert, G. Umana, S. Vercellone, and J. R. Webb

Subjects
Physics, Swift, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Light curve, law.invention, Telescope, Space and Planetary Science, law, Monitoring data, Blazar, business, computer, computer.programming_language, Agile software development
Abstract

Since the CGRO operation in 1991-2000, one of the primary unresolved questions about the blazar gamma-ray emission has been its possible correlation with the low-energy (in particular optical) emission. To help answer this problem, the Whole Earth Blazar Telescope (WEBT) consortium has organized the GLAST-AGILE Support Program (GASP) to provide the optical-to-radio monitoring data to be compared with the gamma-ray detections by the AGILE and GLAST satellites. This new WEBT project started in early September 2007, just before a strong gamma-ray detection of 0716+714 by AGILE. We present the GASP-WEBT optical and radio light curves of this blazar obtained in July-November 2007, about various AGILE pointings at the source. We construct NIR-to-UV spectral energy distributions (SEDs), by assembling GASP-WEBT data together with UV data from the Swift ToO observations of late October. We observe a contemporaneous optical-radio outburst, which is a rare and interesting phenomenon in blazars. The shape of the SEDs during the outburst appears peculiarly wavy because of an optical excess and a UV drop-and-rise. The optical light curve is well sampled during the AGILE pointings, showing prominent and sharp flares. A future cross-correlation analysis of the optical and AGILE data will shed light on the expected relationship between these flares and the gamma-ray events., 5 pages, 5 figures, to be published in A&A (Letters); revised to match the final version (changes in Fig. 5 and related text)

Published
2008

7. The high activity of 3C 454.3 in autumn 2007. Monitoring by the WEBT during the AGILE detection

Author

C. M. Raiteri, M. Villata, W. P. Chen, W.-S. Hsiao, O. M. Kurtanidze, K. Nilsson, V. M. Larionov, M. A. Gurwell, I. Agudo, H. D. Aller, M. F. Aller, E. Angelakis, A. A. Arkharov, U. Bach, M. Böttcher, C. S. Buemi, P. Calcidese, P. Charlot, F. D'Ammando, I. Donnarumma, E. Forné, A. Frasca, L. Fuhrmann, J. L. Gómez, V. A. Hagen-Thorn, S. G. Jorstad, G. N. Kimeridze, T. P. Krichbaum, A. Lähteenmäki, L. Lanteri, G. Latev, J.-F. Le Campion, C.-U. Lee, P. Leto, H.-C. Lin, N. Marchili, E. Marilli, A. P. Marscher, R. Nesci, E. Nieppola, M. G. Nikolashvili, J. Ohlert, E. Ovcharov, D. Principe, T. Pursimo, B. Ragozzine, A. C. Sadun, L. A. Sigua, R. L. Smart, A. Strigachev, L. O. Takalo, M. Tavani, C. Thum, M. Tornikoski, C. Trigilio, K. Uckert, G. Umana, A. Valcheva, S. Vercellone, A. Volvach, H. Wiesemeyer, INAF - Osservatorio Astrofisico di Torino (OATo), Istituto Nazionale di Astrofisica (INAF), Laboratoire de Physico-Chimie de l'Atmosphère (LPCA), Centre National de la Recherche Scientifique (CNRS)-Université du Littoral Côte d'Opale, Laboratoire de chimie bactérienne (LCB), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Fujian Institute of Research on the Structure of Matter, National Engineering Research Center for Optoelectronic Crystalline Materials, Chinese Academy of Sciences, Insitute of Geology China Earthquake Administration Beijing 100029, China (X.X., G.C., W.C.) (INSITUTE OF GEOLOGY), Insitute of Geology, ECE Dept., University of Wisconsin-Madison, Harbin Institute of Technology (HIT), Department of Information Science and Media Studies [Bergen], University of Bergen (UIB), Institute of Geology, Chinese Academy of Sciences [Changchun Branch] (CAS), Linköping University (LIU), Department of Mechanical Engineering, National Chung-Hsing University, Research Center for Environmental Changes, Institute of Earthquake Prediction Research, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université du Littoral Côte d'Opale (ULCO)-Centre National de la Recherche Scientifique (CNRS), Department of Information Science and Media Studies [Bergen] (UiB), University of Bergen (UiB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Raiteri CM, Villata M, Chen WP, Hsiao WS, Kurtanidze OM, Nilsson K, Larionov VM, Gurwell MA, Agudo I, Aller HD, Aller MF, Angelakis E, Arkharov AA, Bach U, Bottcher M, Buemi CS, Calcidese P, Charlot P, DAmmando F, Donnarumma I, Forne E, Frasca A, Fuhrmann L, Gomez JL, Hagen-Thorn VA, Jorstad SG, Kimeridze GN, Krichbaum TP, Lahteenmaki A, Lanteri L, Latev G, Le Campion JF, Lee CU, Leto P, Lin HC, Marchili N, Marilli E, Marscher AP, Nesci R, Nieppola E, Nikolashvili MG, Ohlert J, Ovcharov E, Principe D, Pursimo T, Ragozzine B, Sadun AC, Sigua LA, Smart RL, Strigachev A, Takalo LO, Tavani M, Thum C, Tornikoski M, Trigilio C, Uckert K, Umana G, Valcheva A, Vercellone S, Volvach A, and Wiesemeyer H

Subjects
Brightness, Swift Gamma-Ray Burst Mission, 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, Extinction (astronomy), galaxies: active, FOS: Physical sciences, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, galaxies: active -- galaxies: quasars: general -- galaxies: quasars: individual: 3C 454.3, 01 natural sciences, law.invention, Telescope, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], law, 0103 physical sciences, galaxies: quasars: individual: 3C 454.3, Blazar, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics (astro-ph), Astronomy and Astrophysics, Light curve, galaxies: quasars: general, Space and Planetary Science, Satellite
Abstract

The quasar-type blazar 3C 454.3 underwent a phase of high activity in summer and autumn 2007, which was intensively monitored in the radio-to-optical bands by the Whole Earth Blazar Telescope (WEBT). The gamma-ray satellite AGILE detected this source first in late July, and then in November-December 2007. In this letter we present the multifrequency data collected by the WEBT and collaborators during the second AGILE observing period, complemented by a few contemporaneous data from UVOT onboard the Swift satellite. The aim is to trace in detail the behaviour of the synchrotron emission from the blazar jet, and to investigate the contribution from the thermal emission component. Optical data from about twenty telescopes have been homogeneously calibrated and carefully assembled to construct an R-band light curve containing about 1340 data points in 42 days. This extremely well-sampled optical light curve allows us to follow the dramatic flux variability of the source in detail. In addition, we show radio-to-UV spectral energy distributions (SEDs) at different epochs, which represent different brightness levels. In the considered period, the source varied by 2.6 mag in a couple of weeks in the R band. Many episodes of fast (i.e. intranight) variability were observed, most notably on December 12, when a flux increase of about 1.1 mag in 1.5 hours was detected, followed by a steep decrease of about 1.2 mag in 1 hour. The contribution by the thermal component is difficult to assess, due to the uncertainties in the Galactic, and possibly also intrinsic, extinction in the UV band. However, polynomial fitting of radio-to-UV SEDs reveals an increasing spectral bending going towards fainter states, suggesting a UV excess likely due to the thermal emission from the accretion disc., 5 pages, 4 figures, accepted for publication in Astronomy & Astrophysics Letters

Published
2008
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8. Inorganic interpretation of luminescent materials encountered by the Perseverance rover on Mars.

Author

Scheller EL, Bosak T, McCubbin FM, Williford K, Siljeström S, Jakubek RS, Eckley SA, Morris RV, Bykov SV, Kizovski T, Asher S, Berger E, Bower DM, Cardarelli EL, Ehlmann BL, Fornaro T, Fox A, Haney N, Hand K, Roppel R, Sharma S, Steele A, Uckert K, Yanchilina AG, Beyssac O, Farley KA, Henneke J, Heirwegh C, Pedersen DAK, Liu Y, Schmidt ME, Sephton M, Shuster D, and Weiss BP

Abstract

A major objective of the Mars 2020 mission is to sample rocks in Jezero crater that may preserve organic matter for later return to Earth. Using an ultraviolet Raman and luminescence spectrometer, the Perseverance rover detected luminescence signals with maximal intensities at 330 to 350 nanometers and 270 to 290 nanometers that were initially reported as consistent with organics. Here, we test the alternative hypothesis that the 330- to 350-nanometer and 270- to 290-nanometer luminescence signals trace Ce 3+ in phosphate and silicate defects, respectively. By comparing the distributions of luminescence signals with the rover detections of x-ray fluorescence from P 2 O 5 and Si-bearing materials, we show that, while an organic origin is not excluded, the observed luminescence can be explained by purely inorganic materials. These findings highlight the importance of eventual laboratory analyses to detect and characterize organic compounds in the returned samples.

Published
2024
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9. Diverse organic-mineral associations in Jezero crater, Mars.

Author

Sharma S, Roppel RD, Murphy AE, Beegle LW, Bhartia R, Steele A, Hollis JR, Siljeström S, McCubbin FM, Asher SA, Abbey WJ, Allwood AC, Berger EL, Bleefeld BL, Burton AS, Bykov SV, Cardarelli EL, Conrad PG, Corpolongo A, Czaja AD, DeFlores LP, Edgett K, Farley KA, Fornaro T, Fox AC, Fries MD, Harker D, Hickman-Lewis K, Huggett J, Imbeah S, Jakubek RS, Kah LC, Lee C, Liu Y, Magee A, Minitti M, Moore KR, Pascuzzo A, Rodriguez Sanchez-Vahamonde C, Scheller EL, Shkolyar S, Stack KM, Steadman K, Tuite M, Uckert K, Werynski A, Wiens RC, Williams AJ, Winchell K, Kennedy MR, and Yanchilina A

Abstract

The presence and distribution of preserved organic matter on the surface of Mars can provide key information about the Martian carbon cycle and the potential of the planet to host life throughout its history. Several types of organic molecules have been previously detected in Martian meteorites 1 and at Gale crater, Mars 2-4 . Evaluating the diversity and detectability of organic matter elsewhere on Mars is important for understanding the extent and diversity of Martian surface processes and the potential availability of carbon sources 1,5,6 . Here we report the detection of Raman and fluorescence spectra consistent with several species of aromatic organic molecules in the Máaz and Séítah formations within the Crater Floor sequences of Jezero crater, Mars. We report specific fluorescence-mineral associations consistent with many classes of organic molecules occurring in different spatial patterns within these compositionally distinct formations, potentially indicating different fates of carbon across environments. Our findings suggest there may be a diversity of aromatic molecules prevalent on the Martian surface, and these materials persist despite exposure to surface conditions. These potential organic molecules are largely found within minerals linked to aqueous processes, indicating that these processes may have had a key role in organic synthesis, transport or preservation., (© 2023. The Author(s).)

Published
2023
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10. The Development and Demonstration of the Portable Acousto-Optic Spectrometer for Astrobiology in Cave Environments.

Author

Chanover NJ, Uckert K, Voelz DG, and Boston P

Abstract

Planetary caves are desirable environments for the search for biosignatures corresponding to extant or extinct extraterrestrial life due to the protection they offer from surface-level solar radiation and ionizing particles. Near-infrared (NIR) reflectance spectroscopy is one of a multitude of techniques that, when taken together, can provide a comprehensive understanding of the geomicrobiology in planetary subsurface regions. To that end, we developed two portable NIR spectrometers that employ acousto-optic tunable filters and demonstrated them in three geochemically distinct cave environments. The instruments were deployed both as stand-alone spectrometers positioned against the targets manually and as a component of an instrument payload mounted on a quadruped robot capable of vertical excursions of several meters. In situ measurements of calcium carbonates, sulfates, metal oxides, and microbial colonies and mats revealed spectral signatures that enable a distinction between the targets of interest and the underlying substrates. The ruggedness and portability of the instruments, and their low size, weight, and power, spectral agility, and active illumination make AOTF-based spectrometers ideally suited for studies of planetary caves., (© 2023 The Authors. Earth and Space Science published by Wiley Periodicals LLC on behalf of American Geophysical Union.)

Published
2023
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