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Bocková J, Jones NC, Hoffmann SV, Meinert C. The astrochemical evolutionary traits of phospholipid membrane homochirality. Nat Rev Chem 2024; 8:652-664. [PMID: 39025922 DOI: 10.1038/s41570-024-00627-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2024] [Indexed: 07/20/2024]
Abstract
Compartmentalization is crucial for the evolution of life. Present-day phospholipid membranes exhibit a high level of complexity and species-dependent homochirality, the so-called lipid divide. It is possible that less stable, yet more dynamic systems, promoting out-of-equilibrium environments, facilitated the evolution of life at its early stages. The composition of the preceding primitive membranes and the evolutionary route towards complexity and homochirality remain unexplained. Organics-rich carbonaceous chondrites are evidence of the ample diversity of interstellar chemistry, which may have enriched the prebiotic milieu on early Earth. This Review evaluates the detections of simple amphiphiles - likely ancestors of membrane phospholipids - in extraterrestrial samples and analogues, along with potential pathways to form primitive compartments on primeval Earth. The chiroptical properties of the chiral backbones of phospholipids provide a guide for future investigations into the origins of phospholipid membrane homochirality. We highlight a plausible common pathway towards homochirality of lipids, amino acids, and sugars starting from enantioenriched monomers. Finally, given their high recalcitrance and resistance to degradation, lipids are among the best candidate biomarkers in exobiology.
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Affiliation(s)
- Jana Bocková
- Institut de Chimie de Nice, CNRS UMR 7272, Université Côte d'Azur, Nice, France
| | - Nykola C Jones
- ISA, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark
| | - Søren V Hoffmann
- ISA, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark
| | - Cornelia Meinert
- Institut de Chimie de Nice, CNRS UMR 7272, Université Côte d'Azur, Nice, France.
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2
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Khawaja N, Hortal Sánchez L, O'Sullivan TR, Bloema J, Napoleoni M, Klenner F, Beinlich A, Hillier J, John T, Postberg F. Laboratory characterization of hydrothermally processed oligopeptides in ice grains emitted by Enceladus and Europa. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2024; 382:20230201. [PMID: 38736335 DOI: 10.1098/rsta.2023.0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Accepted: 01/30/2024] [Indexed: 05/14/2024]
Abstract
The Cassini mission provided evidence for a global subsurface ocean and ongoing hydrothermal activity on Enceladus, based on results from Cassini's mass spectrometers. Laboratory simulations of hydrothermal conditions on icy moons are needed to further constrain the composition of ejected ice grains containing hydrothermally altered organic material. Here, we present results from our newly established facility to simulate the processing of ocean material within the temperature range 80-150°C and the pressure range 80-130 bar, representing conditions suggested for the water-rock interface on Enceladus. With this new facility, we investigate the hydrothermal processing of triglycine (GGG) peptide and, for the first time, analyse the extracted samples using laser-induced liquid beam ion desorption (LILBID) mass spectrometry, a laboratory analogue for impact ionization mass spectrometry of ice grains in space. We outline an approach to elucidate hydrothermally processed GGG in ice grains ejected from icy moons based on characteristic differences between GGG anion and cation mass spectra. These differences are linked to hydrothermal processing and thus provide a fingerprint of hydrothermal activity on extraterrestrial bodies. These results will serve as important guidelines for biosignatures potentially obtained by a future Enceladus mission and the SUrface Dust Analyzer (SUDA) instrument onboard Europa Clipper. This article is part of the theme issue 'Dust in the Solar System and beyond'.
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Affiliation(s)
- Nozair Khawaja
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
- Institute of Space Systems, University of Stuttgart , Stuttgart 70569, Germany
| | - Lucía Hortal Sánchez
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Thomas R O'Sullivan
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Judith Bloema
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Maryse Napoleoni
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Fabian Klenner
- Department of Earth and Space Sciences, University of Washington , Seattle, WA 98195, USA
| | - Andreas Beinlich
- Department of Mineralogy and Petrology, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Jon Hillier
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Timm John
- Department of Mineralogy and Petrology, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
| | - Frank Postberg
- Department of Planetary Sciences and Remote Sensing, Institut für Geologische Wissenschaften, Freie Universität Berlin , Malteserstraße, Berlin 12249, Germany
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3
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Klenner F, Bönigk J, Napoleoni M, Hillier J, Khawaja N, Olsson-Francis K, Cable ML, Malaska MJ, Kempf S, Abel B, Postberg F. How to identify cell material in a single ice grain emitted from Enceladus or Europa. SCIENCE ADVANCES 2024; 10:eadl0849. [PMID: 38517965 PMCID: PMC10959401 DOI: 10.1126/sciadv.adl0849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 02/20/2024] [Indexed: 03/24/2024]
Abstract
Icy moons like Enceladus, and perhaps Europa, emit material sourced from their subsurface oceans into space via plumes of ice grains and gas. Both moons are prime targets for astrobiology investigations. Cassini measurements revealed a large compositional diversity of emitted ice grains with only 1 to 4% of Enceladus's plume ice grains containing organic material in high concentrations. Here, we report experiments simulating mass spectra of ice grains containing one bacterial cell, or fractions thereof, as encountered by advanced instruments on board future space missions to Enceladus or Europa, such as the SUrface Dust Analyzer onboard NASA's upcoming Europa Clipper mission at flyby speeds of 4 to 6 kilometers per second. Mass spectral signals characteristic of the bacteria are shown to be clearly identifiable by future missions, even if an ice grain contains much less than one cell. Our results demonstrate the advantage of analyses of individual ice grains compared to a diluted bulk sample in a heterogeneous plume.
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Affiliation(s)
- Fabian Klenner
- Department of Earth and Space Sciences, University of Washington, Seattle, WA, USA
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Janine Bönigk
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Maryse Napoleoni
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Jon Hillier
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Nozair Khawaja
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Karen Olsson-Francis
- Faculty of Science, Technology, Engineering and Mathematics, The Open University, Milton Keynes, UK
| | - Morgan L. Cable
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Michael J. Malaska
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Sascha Kempf
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA
| | - Bernd Abel
- Institute of Chemical Technology, University of Leipzig, Leipzig, Germany
- Leibniz-Institute of Surface Engineering (IOM), Leipzig, Germany
| | - Frank Postberg
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
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4
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Barge LM, Fournier GP. Considerations for Detecting Organic Indicators of Metabolism on Enceladus. ASTROBIOLOGY 2024; 24:328-338. [PMID: 38507694 DOI: 10.1089/ast.2023.0074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
Enceladus is of interest to astrobiology and the search for life since it is thought to host active hydrothermal activity and habitable conditions. It is also possible that the organics detected on Enceladus may indicate an active prebiotic or biotic system; in particular, the conditions on Enceladus may favor mineral-driven protometabolic reactions. When including metabolism-related biosignatures in Enceladus mission concepts, it is necessary to base these in a clearer understanding of how these signatures could also be produced prebiotically. In addition, postulating which biological metabolisms to look for on Enceladus requires a non-Earth-centric approach since the details of biological metabolic pathways are heavily shaped by adaptation to geochemical conditions over the planet's history. Creating metabolism-related organic detection objectives for Enceladus missions, therefore, requires consideration of how metabolic systems may operate differently on another world, while basing these speculations on observed Earth-specific microbial processes. In addition, advances in origin-of-life research can play a critical role in distinguishing between interpretations of any future organic detections on Enceladus, and the discovery of an extant prebiotic system would be a transformative astrobiological event in its own right.
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Affiliation(s)
- Laura M Barge
- Planetary Science Section, NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Gregory P Fournier
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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5
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Burke SE, Auvil ZA, Hanold KA, Continetti RE. Detection of intact amino acids with a hypervelocity ice grain impact mass spectrometer. Proc Natl Acad Sci U S A 2023; 120:e2313447120. [PMID: 38048472 PMCID: PMC10723046 DOI: 10.1073/pnas.2313447120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 10/23/2023] [Indexed: 12/06/2023] Open
Abstract
Astrobiology studies are a top priority in answering one of the most fundamental questions in planetary science: Is there life beyond Earth? Saturn's icy moon Enceladus is a prime target in the search for life in our solar system, identified by NASA as the second-highest priority site for a flagship mission in the next decade. The orbital sampling technique of impact ionization mass spectrometry indicated the presence of complex organics in the small icy plume particles ejected by Enceladus encountered previously by Cassini. However, high interaction velocities caused ambiguity as to the origin and identity of the organics. Laboratory validation of this technique is needed to show that biosignature molecules can survive an impact at hypervelocity speeds for detection. Here, we present results on the hypervelocity impact of organic-laden submicron ice grains for in situ mass spectrometric characterization with the first technique to accurately replicate this plume sampling scenario: the Hypervelocity Ice Grain Impact Mass Spectrometer. Our results show good agreement with Cassini data at comparable compositions. We show that amino acids entrained in ice grains can be detected intact after impact at speeds up to 4.2 km/s and that salt reduces their detectability, validating the predictions from other model systems. Our results provide a benchmark for this orbital sampling method to successfully detect signs of life and for the interpretation of past and future data. This work has implications not only for a potential Enceladus mission but also for the forthcoming Europa Clipper mission.
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Affiliation(s)
- Sally E. Burke
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
| | - Zachary A. Auvil
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
| | - Karl A. Hanold
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
| | - Robert E. Continetti
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA92093-0340
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6
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Vance SD, Craft KL, Shock E, Schmidt BE, Lunine J, Hand KP, McKinnon WB, Spiers EM, Chivers C, Lawrence JD, Wolfenbarger N, Leonard EJ, Robinson KJ, Styczinski MJ, Persaud DM, Steinbrügge G, Zolotov MY, Quick LC, Scully JEC, Becker TM, Howell SM, Clark RN, Dombard AJ, Glein CR, Mousis O, Sephton MA, Castillo-Rogez J, Nimmo F, McEwen AS, Gudipati MS, Jun I, Jia X, Postberg F, Soderlund KM, Elder CM. Investigating Europa's Habitability with the Europa Clipper. SPACE SCIENCE REVIEWS 2023; 219:81. [PMID: 38046182 PMCID: PMC10687213 DOI: 10.1007/s11214-023-01025-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 11/03/2023] [Indexed: 12/05/2023]
Abstract
The habitability of Europa is a property within a system, which is driven by a multitude of physical and chemical processes and is defined by many interdependent parameters, so that its full characterization requires collaborative investigation. To explore Europa as an integrated system to yield a complete picture of its habitability, the Europa Clipper mission has three primary science objectives: (1) characterize the ice shell and ocean including their heterogeneity, properties, and the nature of surface-ice-ocean exchange; (2) characterize Europa's composition including any non-ice materials on the surface and in the atmosphere, and any carbon-containing compounds; and (3) characterize Europa's geology including surface features and localities of high science interest. The mission will also address several cross-cutting science topics including the search for any current or recent activity in the form of thermal anomalies and plumes, performing geodetic and radiation measurements, and assessing high-resolution, co-located observations at select sites to provide reconnaissance for a potential future landed mission. Synthesizing the mission's science measurements, as well as incorporating remote observations by Earth-based observatories, the James Webb Space Telescope, and other space-based resources, to constrain Europa's habitability, is a complex task and is guided by the mission's Habitability Assessment Board (HAB).
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Affiliation(s)
- Steven D. Vance
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Kathleen L. Craft
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD USA
| | - Everett Shock
- School of Earth & Space Exploration and School of Molecular Sciences, Arizona State University, Tempe, AZ USA
| | - Britney E. Schmidt
- Department of Astronomy and Department of Earth & Atmospheric Sciences, Cornell University, Ithaca, NY USA
| | - Jonathan Lunine
- Department of Astronomy and Department of Earth & Atmospheric Sciences, Cornell University, Ithaca, NY USA
| | - Kevin P. Hand
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - William B. McKinnon
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University in St. Louis, Saint Louis, MO USA
| | - Elizabeth M. Spiers
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
| | - Chase Chivers
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
- Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA USA
| | - Justin D. Lawrence
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
- Honeybee Robotics, Altadena, CA USA
| | - Natalie Wolfenbarger
- Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, TX USA
| | - Erin J. Leonard
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | | | | | - Divya M. Persaud
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Gregor Steinbrügge
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Mikhail Y. Zolotov
- School of Earth & Space Exploration and School of Molecular Sciences, Arizona State University, Tempe, AZ USA
| | | | | | | | - Samuel M. Howell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | | | - Andrew J. Dombard
- Dept. of Earth and Environmental Sciences, University of Illinois Chicago, Chicago, USA
| | | | - Olivier Mousis
- Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
| | - Mark A. Sephton
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, United Kingdom
| | | | - Francis Nimmo
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA USA
| | - Alfred S. McEwen
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ USA
| | - Murthy S. Gudipati
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Insoo Jun
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Xianzhe Jia
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI USA
| | - Frank Postberg
- Institut für Geologische Wissenschaften, Freie Universität Berlin, Berlin, Germany
| | - Krista M. Soderlund
- Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, TX USA
| | - Catherine M. Elder
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
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7
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Malaterre C, Ten Kate IL, Baqué M, Debaille V, Grenfell JL, Javaux EJ, Khawaja N, Klenner F, Lara YJ, McMahon S, Moore K, Noack L, Patty CHL, Postberg F. Is There Such a Thing as a Biosignature? ASTROBIOLOGY 2023; 23:1213-1227. [PMID: 37962841 DOI: 10.1089/ast.2023.0042] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The concept of a biosignature is widely used in astrobiology to suggest a link between some observation and a biological cause, given some context. The term itself has been defined and used in several ways in different parts of the scientific community involved in the search for past or present life on Earth and beyond. With the ongoing acceleration in the search for life in distant time and/or deep space, there is a need for clarity and accuracy in the formulation and reporting of claims. Here, we critically review the biosignature concept(s) and the associated nomenclature in light of several problems and ambiguities emphasized by recent works. One worry is that these terms and concepts may imply greater certainty than is usually justified by a rational interpretation of the data. A related worry is that terms such as "biosignature" may be inherently misleading, for example, because the divide between life and non-life-and their observable effects-is fuzzy. Another worry is that different parts of the multidisciplinary community may use non-equivalent or conflicting definitions and conceptions, leading to avoidable confusion. This review leads us to identify a number of pitfalls and to suggest how they can be circumvented. In general, we conclude that astrobiologists should exercise particular caution in deciding whether and how to use the concept of biosignature when thinking and communicating about habitability or life. Concepts and terms should be selected carefully and defined explicitly where appropriate. This would improve clarity and accuracy in the formulation of claims and subsequent technical and public communication about some of the most profound and important questions in science and society. With this objective in mind, we provide a checklist of questions that scientists and other interested parties should ask when assessing any reported detection of a "biosignature" to better understand exactly what is being claimed.
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Affiliation(s)
- Christophe Malaterre
- Département de philosophie, Chaire de recherche du Canada en philosophie des sciences de la vie, Université du Québec à Montréal (UQAM), Montréal, Québec, Canada
- Centre interuniversitaire de recherche sur la science et la technologie (CIRST), Université du Québec à Montréal (UQAM), Montréal, Québec, Canada
| | - Inge Loes Ten Kate
- Department of Earth Sciences, Utrecht University, Utrecht, the Netherlands
| | - Mickael Baqué
- Planetary Laboratories Department, Institute of Planetary Research, German Aerospace Center (DLR), Berlin, Germany
| | - Vinciane Debaille
- Laboratoire G-Time, Université libre de Bruxelles, Brussels, Belgium
| | - John Lee Grenfell
- Department of Extrasolar Planets and Atmospheres, Institute of Planetary Research, German Aerospace Center (DLR), Berlin, Germany
| | - Emmanuelle J Javaux
- Early Life Traces & Evolution-Astrobiology, UR Astrobiology, University of Liège, Liège, Belgium
| | - Nozair Khawaja
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Fabian Klenner
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
- Department of Earth and Space Sciences, University of Washington, Seattle, Washington, USA
| | - Yannick J Lara
- Early Life Traces & Evolution-Astrobiology, UR Astrobiology, University of Liège, Liège, Belgium
| | - Sean McMahon
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
- School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Keavin Moore
- Department of Earth & Planetary Sciences, McGill University, Montreal, Québec, Canada
- Trottier Space Institute, McGill University, Montreal, Québec, Canada
| | - Lena Noack
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - C H Lucas Patty
- Physikalisches Institut, Universität Bern, Bern, Switzerland
- Center for Space and Habitability, Universität Bern, Bern, Switzerland
| | - Frank Postberg
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
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8
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Weber JM, Marlin TC, Prakash M, Teece BL, Dzurilla K, Barge LM. A Review on Hypothesized Metabolic Pathways on Europa and Enceladus: Space-Flight Detection Considerations. Life (Basel) 2023; 13:1726. [PMID: 37629583 PMCID: PMC10456045 DOI: 10.3390/life13081726] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/01/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Enceladus and Europa, icy moons of Saturn and Jupiter, respectively, are believed to be habitable with liquid water oceans and therefore are of interest for future life detection missions and mission concepts. With the limited data from missions to these moons, many studies have sought to better constrain these conditions. With these constraints, researchers have, based on modeling and experimental studies, hypothesized a number of possible metabolisms that could exist on Europa and Enceladus if these worlds host life. The most often hypothesized metabolisms are methanogenesis for Enceladus and methane oxidation/sulfate reduction on Europa. Here, we outline, review, and compare the best estimated conditions of each moon's ocean. We then discuss the hypothetical metabolisms that have been suggested to be present on these moons, based on laboratory studies and Earth analogs. We also detail different detection methods that could be used to detect these hypothetical metabolic reactions and make recommendations for future research and considerations for future missions.
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Affiliation(s)
- Jessica M. Weber
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA (B.L.T.); (K.D.); (L.M.B.)
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9
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Spesyvyi A, Žabka J, Polášek M, Charvat A, Schmidt J, Postberg F, Abel B. Charged Ice Particle Beams with Selected Narrow Mass and Kinetic Energy Distributions. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:878-892. [PMID: 37018538 DOI: 10.1021/jasms.2c00357] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Small ice particles play an important role in atmospheric and extraterrestrial chemistry. Circumplanetary ice particles that are encountered by space probes at hypervelocities play a critical role in the determination of surface and subsurface properties of their source bodies. Here we present an apparatus for the generation of low-intensity beams of single mass-selected charged ice particles under vacuum. They are produced via electrospray ionization of water at atmospheric pressure and undergo evaporative cooling when transferred to vacuum through an atmospheric vacuum interface. m/z selection is achieved through two subsequent quadrupole mass filters operated in the variable-frequency mode within a range of m/z values between 8 × 104 and 3 × 107. Velocity and charge of the selected particles are measured using a nondestructive single-pass image charge detector. From the known electrostatic acceleration potentials and settings of the quadrupoles the particle masses could be obtained and be accurately controlled. It has been shown that the droplets are frozen within the transit time of the apparatus such that ice particles are present after the quadrupole stages and finally detected. The demonstrated correspondence between particle mass and specific quadrupole potentials in this device allows preparation of beams of single particles with a repetition rate between 0.1 and 1 Hz with various diameter distributions from 50 to 1000 nm at 30-250 eV of kinetic energy per charge. This corresponds to velocities and particle masses quickly available between 600 m/s (80 nm) and 50 m/s (900 nm) and particle charge numbers (positive) between 103 and 104[e], depending upon size.
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Affiliation(s)
- Anatolii Spesyvyi
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 2155/3, 18223 Prague 8, Czech Republic
| | - Ján Žabka
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 2155/3, 18223 Prague 8, Czech Republic
| | - Miroslav Polášek
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova 2155/3, 18223 Prague 8, Czech Republic
| | - Ales Charvat
- Institute of Chemical Technology and Wilhelm-Ostwald-Institute of Physical and Theoretical Chemistry, Linnestrasse 3, D-04103 Leipzig, Germany
- Leibniz Institute of Surface Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany
| | - Jürgen Schmidt
- Institute of Geological Sciences, Freie Universität Berlin, Malteserstraße 74-100, D-12249 Berlin, Germany
| | - Frank Postberg
- Institute of Geological Sciences, Freie Universität Berlin, Malteserstraße 74-100, D-12249 Berlin, Germany
| | - Bernd Abel
- Institute of Chemical Technology and Wilhelm-Ostwald-Institute of Physical and Theoretical Chemistry, Linnestrasse 3, D-04103 Leipzig, Germany
- Leibniz Institute of Surface Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany
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10
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Dannenmann M, Klenner F, Bönigk J, Pavlista M, Napoleoni M, Hillier J, Khawaja N, Olsson-Francis K, Cable ML, Malaska MJ, Abel B, Postberg F. Toward Detecting Biosignatures of DNA, Lipids, and Metabolic Intermediates from Bacteria in Ice Grains Emitted by Enceladus and Europa. ASTROBIOLOGY 2023; 23:60-75. [PMID: 36454287 DOI: 10.1089/ast.2022.0063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The reliable identification of biosignatures is key to the search for life elsewhere. On ocean worlds like Enceladus or Europa, this can be achieved by impact ionization mass spectrometers, such as the SUrface Dust Analyzer (SUDA) on board NASA's upcoming Europa Clipper mission. During spacecraft flybys, these instruments can sample ice grains formed from subsurface water and emitted by these moons. Previous laboratory analog experiments have demonstrated that SUDA-type instruments could identify amino acids, fatty acids, and peptides in ice grains and discriminate between their abiotic and biotic origins. Here, we report experiments simulating impact ionization mass spectra of ice grains containing DNA, lipids, and metabolic intermediates extracted from two bacterial cultures: Escherichia coli and Sphingopyxis alaskensis. Salty Enceladan or Europan ocean waters were simulated using matrices with different NaCl concentrations. Characteristic mass spectral signals, such as DNA nucleobases, are clearly identifiable at part-per-million-level concentrations. Mass spectra of all substances exhibit unambiguous biogenic patterns, which in some cases show significant differences between the two bacterial species. Sensitivity to the biosignatures decreases with increasing matrix salinity. The experimental parameters indicate that future impact ionization mass spectrometers will be most sensitive to the investigated biosignatures for ice grain encounter speeds of 4-6 km/s.
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Affiliation(s)
- Marie Dannenmann
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Fabian Klenner
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Janine Bönigk
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Miriam Pavlista
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Maryse Napoleoni
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Jon Hillier
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Nozair Khawaja
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
| | - Karen Olsson-Francis
- AstrobiologyOU, Faculty of Science, Technology, Engineering & Mathematics, The Open University, Milton Keynes, United Kingdom
| | - Morgan L Cable
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Michael J Malaska
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Bernd Abel
- Leibniz-Institute of Surface Engineering (IOM), Leipzig, Germany
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, Leipzig University, Leipzig, Germany
| | - Frank Postberg
- Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany
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11
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Madzunkova S, Nikolić D. Method for Accurate Detection of Amino Acids and Mycotoxins in Planetary Atmospheres. Life (Basel) 2022; 12:2122. [PMID: 36556487 PMCID: PMC9784085 DOI: 10.3390/life12122122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/28/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
We present a systematic analysis of a large number of mass spectra accumulated as the number of ion fragments recorded in unit mass-to-charge detector channels. The method retrieves the abundances of detected species using an efficient deconvolution algorithm, which relies on fragment pattern recognition, mass calibration, and background correction. The abundance analysis identifies target species, amino acids, and mycotoxins through their characteristic fragmentation patterns in the presence of an increasing number of interfering species. The method offered robust and efficient retrieval of abundances of metabolic molecules in complex mixtures obscured by a wide range of toxic compounds.
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Affiliation(s)
- Sigrid Madzunkova
- La Cañada High School, 4463 Oak Grove Dr, La Cañada Flintridge, CA 91011, USA
| | - Dragan Nikolić
- California Institute of Technology, Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA
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12
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Špaček J, Benner SA. Agnostic Life Finder (ALF) for Large-Scale Screening of Martian Life During In Situ Refueling. ASTROBIOLOGY 2022; 22:1255-1263. [PMID: 35796703 DOI: 10.1089/ast.2021.0070] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Before the first humans depart for Mars in the next decade, hundreds of tons of martian water-ice must be harvested to produce propellant for the return vehicle, a process known as in situ resource utilization (ISRU). We describe here an instrument, the Agnostic Life Finder (ALF), that is an inexpensive life-detection add-on to ISRU. ALF exploits a well-supported view that informational genetic biopolymers in life in water must have two structural features: (1) Informational biopolymers must carry a repeating charge; they must be polyelectrolytes. (2) Their building blocks must fit into an aperiodic crystal structure; the building blocks must be size-shape regular. ALF exploits the first structural feature to extract polyelectrolytes from ∼10 cubic meters of mined martian water by applying a voltage gradient perpendicularly to the water's flow. This gradient diverts polyelectrolytes from the flow toward their respective electrodes (polyanions to the anode, polycations to the cathode), where they are captured in cartridges before they encounter the electrodes. There, they can later be released to analyze their building blocks, for example, by mass spectrometry or nanopore. Upstream, martian cells holding martian informational polyelectrolytes are disrupted by ultrasound. To manage the (unknown) conductivity of the water due to the presence of salts, the mined water is preconditioned by electrodialysis using porous membranes. ALF uses only resources and technology that must already be available for ISRU. Thus, life detection is easily and inexpensively integrated into SpaceX or NASA ISRU missions.
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Affiliation(s)
- Jan Špaček
- Firebird Biomolecular Sciences, LLC, Alachua, Florida, USA
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13
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Mora MF, Kok MGM, Noell A, Willis PA. Detection of Biosignatures by Capillary Electrophoresis Mass Spectrometry in the Presence of Salts Relevant to Ocean Worlds Missions. ASTROBIOLOGY 2022; 22:914-925. [PMID: 35913998 DOI: 10.1089/ast.2021.0091] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Capillary electrophoresis (CE) is a promising liquid-based technique for in situ chemical analysis on ocean worlds that allows the detection of a wide range of organic molecules relevant to the search for life. CE coupled with mass spectrometry (MS) is particularly valuable as it also enables the discovery of unknown compounds. Here we demonstrate that CE coupled to MS via electrospray ionization (ESI) can readily analyze samples containing up to half the saturation levels of salts relevant to ocean worlds when using 5 M acetic acid as the separation media. A mixture containing amino acids, peptides, nucleobases, and nucleosides was analyzed in the presence of two salts, NaCl and MgSO4, based on their relevance to Europa and Enceladus. We demonstrate here CE-MS limits of detection for these organics ranging from 0.05 to 1 μM (8 to 89 ppb) in the absence of salts. More importantly, we demonstrate here for the first time that organics in the low micromolar range (1-50 μM) are detected by CE-MS in the presence of 3 M NaCl without desalting, preconcentration, or derivatization. This demonstration highlights how CE-MS is uniquely suited for organic analysis on future missions to ocean worlds.
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Affiliation(s)
- Maria F Mora
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Miranda G M Kok
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Aaron Noell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Peter A Willis
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
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14
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Barge LM, Rodriguez LE, Weber JM, Theiling BP. Determining the "Biosignature Threshold" for Life Detection on Biotic, Abiotic, or Prebiotic Worlds. ASTROBIOLOGY 2022; 22:481-493. [PMID: 34898272 DOI: 10.1089/ast.2021.0079] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The field of prebiotic chemistry has demonstrated that complex organic chemical systems that exhibit various life-like properties can be produced abiotically in the laboratory. Understanding these chemical systems is important for astrobiology and life detection since we do not know the extent to which prebiotic chemistry might exist or have existed on other worlds. Nor do we know what signatures are diagnostic of an extant or "failed" prebiotic system. On Earth, biology has suppressed most abiotic organic chemistry and overprints geologic records of prebiotic chemistry; therefore, it is difficult to validate whether chemical signatures from future planetary missions are remnant or extant prebiotic systems. The "biosignature threshold" between whether a chemical signature is more likely to be produced by abiotic versus biotic chemistry on a given world could vary significantly, depending on the particular environment, and could change over time, especially if life were to emerge and diversify on that world. To interpret organic signatures detected during a planetary mission, we advocate for (1) gaining a more complete understanding of prebiotic/abiotic chemical possibilities in diverse planetary environments and (2) involving experimental prebiotic samples as analogues when generating comparison libraries for "life-detection" mission instruments.
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Affiliation(s)
- Laura M Barge
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Laura E Rodriguez
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Jessica M Weber
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
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15
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Chirality in Organic and Mineral Systems: A Review of Reactivity and Alteration Processes Relevant to Prebiotic Chemistry and Life Detection Missions. Symmetry (Basel) 2022. [DOI: 10.3390/sym14030460] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Chirality is a central feature in the evolution of biological systems, but the reason for biology’s strong preference for specific chiralities of amino acids, sugars, and other molecules remains a controversial and unanswered question in origins of life research. Biological polymers tend toward homochiral systems, which favor the incorporation of a single enantiomer (molecules with a specific chiral configuration) over the other. There have been numerous investigations into the processes that preferentially enrich one enantiomer to understand the evolution of an early, racemic, prebiotic organic world. Chirality can also be a property of minerals; their interaction with chiral organics is important for assessing how post-depositional alteration processes could affect the stereochemical configuration of simple and complex organic molecules. In this paper, we review the properties of organic compounds and minerals as well as the physical, chemical, and geological processes that affect organic and mineral chirality during the preservation and detection of organic compounds. We provide perspectives and discussions on the reactions and analytical techniques that can be performed in the laboratory, and comment on the state of knowledge of flight-capable technologies in current and future planetary missions, with a focus on organics analysis and life detection.
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16
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Salter TL, Magee BA, Waite JH, Sephton MA. Mass Spectrometric Fingerprints of Bacteria and Archaea for Life Detection on Icy Moons. ASTROBIOLOGY 2022; 22:143-157. [PMID: 35021862 DOI: 10.1089/ast.2020.2394] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The icy moons of the outer Solar System display evidence of subsurface liquid water and, therefore, potential habitability for life. Flybys of Saturn's moon Enceladus by the Cassini spacecraft have provided measurements of material from plumes that suggest hydrothermal activity and the presence of organic matter. Jupiter's moon Europa may have similar plumes and is the target for the forthcoming Europa Clipper mission that carries a high mass resolution and high sensitivity mass spectrometer, called the MAss Spectrometer for Planetary EXploration (MASPEX), with the capability for providing detailed characterization of any organic materials encountered. We have performed a series of experiments using pyrolysis-gas chromatography-mass spectrometry to characterize the mass spectrometric fingerprints of microbial life. A range of extremophile Archaea and Bacteria have been analyzed and the laboratory data converted to MASPEX-type signals. Molecular characteristics of protein, carbohydrate, and lipid structures were detected, and the characteristic fragmentation patterns corresponding to these different biological structures were identified. Protein pyrolysis fragments included phenols, nitrogen heterocycles, and cyclic dipeptides. Oxygen heterocycles, such as furans, were detected from carbohydrates. Our data reveal how mass spectrometry on Europa Clipper can aid in the identification of the presence of life, by looking for characteristic bacterial fingerprints that are similar to those from simple Earthly organisms.
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Affiliation(s)
- Tara L Salter
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, United Kingdom
| | - Brian A Magee
- Space Science and Engineering Division, Southwest Research Institute, Boulder, Colorado, USA
| | - J Hunter Waite
- Space Science and Engineering Division, Southwest Research Institute, San Antonio, Texas, USA
| | - Mark A Sephton
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, United Kingdom
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17
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Seaton KM, Cable ML, Stockton AM. Analytical Chemistry in Astrobiology. Anal Chem 2021; 93:5981-5997. [PMID: 33835785 DOI: 10.1021/acs.analchem.0c04271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This Feature introduces and discusses the findings of key analytical techniques used to study planetary bodies in our solar system in the search for life beyond Earth, future missions planned for high-priority astrobiology targets in our solar system, and the challenges we face in performing these investigations.
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Affiliation(s)
- Kenneth Marshall Seaton
- School of Chemistry & Biochemistry, Georgia Institute of Technology, North Avenue NW, Atlanta, Georgia 30332, United States
| | - Morgan Leigh Cable
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Amanda Michelle Stockton
- School of Chemistry & Biochemistry, Georgia Institute of Technology, North Avenue NW, Atlanta, Georgia 30332, United States
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18
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Belousov A, Miller M, Continetti R, Madzunkov S, Simcic J, Nikolic D, Maiwald F, Waller S, Malaska M, Cable M. Sampling Accelerated Micron Scale Ice Particles with a Quadrupole Ion Trap Mass Spectrometer. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1162-1168. [PMID: 33792296 DOI: 10.1021/jasms.0c00442] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The Enceladus plume is a target of astrobiological interest in planetary science since it may carry signs of extraterrestrial life entrapped in ice grains formed from the subsurface ocean of this moon of Saturn. Fly-by mission concepts have been proposed to perform close investigations of the plume, including detailed in situ measurements of chemical composition with a new generation of mass spectrometer instrumentation. Such a scenario involves high-velocity collisions (typically around 5 km/s or higher) of the instrument with the encountered ice grains. Postimpact processes may include molecular fragmentation, impact ionization, and various subsequent chemical reactions that could alter the original material prior to analysis. In order to simulate Enceladus plume fly through conditions, we are developing an ice grain accelerator and have coupled it to the quadrupole ion trap mass spectrometer (QITMS) developed for flight applications. Our experimental setup enables the creation and acceleration of ice particles with well-defined size, charge, and velocity, which are subsequently directed into the QITMS, where they impact the surface of the mass analyzer and the analysis of postimpact, volatilized molecules takes place. In this work, we performed mass spectral analysis of ice grains of ca. 1.3 μm in diameter, accelerated and impacted at velocities up to 1000 m/s, with an upgrade of the accelerator in progress that will enable velocities up to 5000 m/s. We report the first observations of ice grain impacts measured by the QITMS, which were recorded as brief increases in the abundance of water molecules detected within the instrument.
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Affiliation(s)
- Anton Belousov
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Morgan Miller
- University of California San Diego, Mail Code 0340, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Robert Continetti
- University of California San Diego, Mail Code 0340, 9500 Gilman Drive, La Jolla, California 92093-0340, United States
| | - Stojan Madzunkov
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Jurij Simcic
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Dragan Nikolic
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Frank Maiwald
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Sarah Waller
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Michael Malaska
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
| | - Morgan Cable
- NASA Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, United States
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19
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Jaramillo-Botero A, Cable ML, Hofmann AE, Malaska M, Hodyss R, Lunine J. Understanding Hypervelocity Sampling of Biosignatures in Space Missions. ASTROBIOLOGY 2021; 21:421-442. [PMID: 33749334 PMCID: PMC7994429 DOI: 10.1089/ast.2020.2301] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 11/09/2020] [Indexed: 05/08/2023]
Abstract
The atomic-scale fragmentation processes involved in molecules undergoing hypervelocity impacts (HVIs; defined as >3 km/s) are challenging to investigate via experiments and still not well understood. This is particularly relevant for the consistency of biosignals from small-molecular-weight neutral organic molecules obtained during solar system robotic missions sampling atmospheres and plumes at hypervelocities. Experimental measurements to replicate HVI effects on neutral molecules are challenging, both in terms of accelerating uncharged species and isolating the multiple transition states over very rapid timescales (<1 ps). Nonequilibrium first-principles-based simulations extend the range of what is possible with experiments. We report on high-fidelity simulations of the fragmentation of small organic biosignature molecules over the range v = 1-12 km/s, and demonstrate that the fragmentation fraction is a sensitive function of velocity, impact angle, molecular structure, impact surface material, and the presence of surrounding ice shells. Furthermore, we generate interpretable fragmentation pathways and spectra for velocity values above the fragmentation thresholds and reveal how organic molecules encased in ice grains, as would likely be the case for those in "ocean worlds," are preserved at even higher velocities than bare molecules. Our results place ideal spacecraft encounter velocities between 3 and 5 km/s for bare amino and fatty acids and within 4-6 km/s for the same species encased in ice grains and predict the onset of organic fragmentation in ice grains at >5 km/s, both consistent with recent experiments exploring HVI effects using impact-induced ionization and analysis via mass spectrometry and from the analysis of Enceladus organics in Cassini Data. From nanometer-sized ice Ih clusters, we establish that HVI energy is dissipated by ice casings through thermal resistance to the impact shock wave and that an upper fragmentation velocity limit exists at which ultimately any organic contents will be cleaved by the surrounding ice-this provides a fundamental path to characterize micrometer-sized ice grains. Altogether, these results provide quantifiable insights to bracket future instrument design and mission parameters.
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Affiliation(s)
- Andres Jaramillo-Botero
- Chemistry and Chemical Engineering Division, California Institute of Technology, Pasadena, California, USA
| | - Morgan L. Cable
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Amy E. Hofmann
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Michael Malaska
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Robert Hodyss
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Jonathan Lunine
- Department of Astronomy and Carl Sagan Institute, Cornell University, Ithaca, New York, USA
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20
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Abstract
Most definitions of life assume that, at a minimum, life is a physical form of matter distinct from its environment at a lower state of entropy than its surroundings, using energy from the environment for internal maintenance and activity, and capable of autonomous reproduction. These assumptions cover all of life as we know it, though more exotic entities can be envisioned, including organic forms with novel biochemistries, dynamic inorganic matter, and self-replicating machines. The probability that any particular form of life will be found on another planetary body depends on the nature and history of that alien world. So the biospheres would likely be very different on a rocky planet with an ice-covered global ocean, a barren planet devoid of surface liquid, a frigid world with abundant liquid hydrocarbons, on a rogue planet independent of a host star, on a tidally locked planet, on super-Earths, or in long-lived clouds in dense atmospheres. While life at least in microbial form is probably pervasive if rare throughout the Universe, and technologically advanced life is likely much rarer, the chance that an alternative form of life, though not intelligent life, could exist and be detected within our Solar System is a distinct possibility.
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21
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Taubner RS, Olsson-Francis K, Vance SD, Ramkissoon NK, Postberg F, de Vera JP, Antunes A, Camprubi Casas E, Sekine Y, Noack L, Barge L, Goodman J, Jebbar M, Journaux B, Karatekin Ö, Klenner F, Rabbow E, Rettberg P, Rückriemen-Bez T, Saur J, Shibuya T, Soderlund KM. Experimental and Simulation Efforts in the Astrobiological Exploration of Exooceans. SPACE SCIENCE REVIEWS 2020; 216:9. [PMID: 32025060 PMCID: PMC6977147 DOI: 10.1007/s11214-020-0635-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 01/06/2020] [Indexed: 05/05/2023]
Abstract
The icy satellites of Jupiter and Saturn are perhaps the most promising places in the Solar System regarding habitability. However, the potential habitable environments are hidden underneath km-thick ice shells. The discovery of Enceladus' plume by the Cassini mission has provided vital clues in our understanding of the processes occurring within the interior of exooceans. To interpret these data and to help configure instruments for future missions, controlled laboratory experiments and simulations are needed. This review aims to bring together studies and experimental designs from various scientific fields currently investigating the icy moons, including planetary sciences, chemistry, (micro-)biology, geology, glaciology, etc. This chapter provides an overview of successful in situ, in silico, and in vitro experiments, which explore different regions of interest on icy moons, i.e. a potential plume, surface, icy shell, water and brines, hydrothermal vents, and the rocky core.
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Affiliation(s)
- Ruth-Sophie Taubner
- Archaea Biology and Ecogenomics Division, University of Vienna, Vienna, Austria
| | | | | | | | | | | | - André Antunes
- State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau SAR, China
| | | | | | - Lena Noack
- Freie Universität Berlin, Berlin, Germany
| | | | | | | | | | | | | | - Elke Rabbow
- German Aerospace Center (DLR), Cologne, Germany
| | | | | | | | - Takazo Shibuya
- Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
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