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Ni Z, Arevalo R, Bardyn A, Willhite L, Ray S, Southard A, Danell R, Graham J, Li X, Chou L, Briois C, Thirkell L, Makarov A, Brinckerhoff W, Eigenbrode J, Junge K, Nunn BL. Detection of Short Peptides as Putative Biosignatures of Psychrophiles via Laser Desorption Mass Spectrometry. ASTROBIOLOGY 2023; 23:657-669. [PMID: 37134219 DOI: 10.1089/ast.2022.0138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Studies of psychrophilic life on Earth provide chemical clues as to how extraterrestrial life could maintain viability in cryogenic environments. If living systems in ocean worlds (e.g., Enceladus) share a similar set of 3-mer and 4-mer peptides to the psychrophile Colwellia psychrerythraea on Earth, spaceflight technologies and analytical methods need to be developed to detect and sequence these putative biosignatures. We demonstrate that laser desorption mass spectrometry, as implemented by the CORALS spaceflight prototype instrument, enables the detection of protonated peptides, their dimers, and metal adducts. The addition of silicon nanoparticles promotes the ionization efficiency, improves mass resolving power and mass accuracies via reduction of metastable decay, and facilitates peptide de novo sequencing. The CORALS instrument, which integrates a pulsed UV laser source and an Orbitrap™ mass analyzer capable of ultrahigh mass resolving powers and mass accuracies, represents an emerging technology for planetary exploration and a pathfinder for advanced technique development for astrobiological objectives. Teaser: Current spaceflight prototype instrument proposed to visit ocean worlds can detect and sequence peptides that are found enriched in at least one strain of microbe surviving in subzero icy brines via silicon nanoparticle-assisted laser desorption analysis.
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Affiliation(s)
- Ziqin Ni
- University of Maryland, College Park, Maryland, USA
| | | | - Anais Bardyn
- University of Maryland, College Park, Maryland, USA
| | | | - Soumya Ray
- University of Maryland, College Park, Maryland, USA
| | | | - Ryan Danell
- Danell Consulting, Winterville, North Carolina, USA
| | - Jacob Graham
- NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Xiang Li
- NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - Luoth Chou
- NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
- Georgetown University, Washington, DC, USA
| | - Christelle Briois
- Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, Orléans, France
| | - Laurent Thirkell
- Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, Orléans, France
| | | | | | | | - Karen Junge
- University of Washington, Seattle, Washington, USA
| | - Brook L Nunn
- University of Washington, Seattle, Washington, USA
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2
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Dopson M, González-Rosales C, Holmes DS, Mykytczuk N. Eurypsychrophilic acidophiles: From (meta)genomes to low-temperature biotechnologies. Front Microbiol 2023; 14:1149903. [PMID: 37007468 PMCID: PMC10050440 DOI: 10.3389/fmicb.2023.1149903] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 02/16/2023] [Indexed: 03/17/2023] Open
Abstract
Low temperature and acidic environments encompass natural milieus such as acid rock drainage in Antarctica and anthropogenic sites including drained sulfidic sediments in Scandinavia. The microorganisms inhabiting these environments include polyextremophiles that are both extreme acidophiles (defined as having an optimum growth pH < 3), and eurypsychrophiles that grow at low temperatures down to approximately 4°C but have an optimum temperature for growth above 15°C. Eurypsychrophilic acidophiles have important roles in natural biogeochemical cycling on earth and potentially on other planetary bodies and moons along with biotechnological applications in, for instance, low-temperature metal dissolution from metal sulfides. Five low-temperature acidophiles are characterized, namely, Acidithiobacillus ferriphilus, Acidithiobacillus ferrivorans, Acidithiobacillus ferrooxidans, “Ferrovum myxofaciens,” and Alicyclobacillus disulfidooxidans, and their characteristics are reviewed. Our understanding of characterized and environmental eurypsychrophilic acidophiles has been accelerated by the application of “omics” techniques that have aided in revealing adaptations to low pH and temperature that can be synergistic, while other adaptations are potentially antagonistic. The lack of known acidophiles that exclusively grow below 15°C may be due to the antagonistic nature of adaptations in this polyextremophile. In conclusion, this review summarizes the knowledge of eurypsychrophilic acidophiles and places the information in evolutionary, environmental, biotechnological, and exobiology perspectives.
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Affiliation(s)
- Mark Dopson
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden
- *Correspondence: Mark Dopson
| | - Carolina González-Rosales
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden
- Center for Bioinformatics and Genome Biology, Centro Ciencia & Vida, Fundación Ciencia & Vida, Santiago, Chile
| | - David S. Holmes
- Center for Bioinformatics and Genome Biology, Centro Ciencia & Vida, Fundación Ciencia & Vida, Santiago, Chile
- Facultad de Medicina y Ciencia, Universidad San Sebastian, Santiago, Chile
| | - Nadia Mykytczuk
- Goodman School of Mines, Laurentian University, Sudbury, ON, Canada
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Sanderink A, Klenner F, Zymak I, Žabka J, Postberg F, Lebreton JP, Gaubicher B, Charvat A, Abel B, Polášek M, Cherville B, Thirkell L, Briois C. OLYMPIA-LILBID: A New Laboratory Setup to Calibrate Spaceborne Hypervelocity Ice Grain Detectors Using High-Resolution Mass Spectrometry. Anal Chem 2023; 95:3621-3628. [PMID: 36753610 DOI: 10.1021/acs.analchem.2c04429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
The coupling of an Orbitrap-based mass analyzer to the laser-induced liquid beam ion desorption (LILBID) technique has been investigated, with the aim to reproduce the mass spectra recorded by Cassini's Cosmic Dust Analyzer (CDA) in the vicinity of Saturn's icy moon Enceladus. LILBID setups are usually coupled with time-of-flight (TOF) mass analyzers, with a limited mass resolution (∼800 m/Δm). Thanks to the Orbitrap technology, we developed a unique analytical setup that is able to simulate hypervelocity ice grains' impact in the laboratory (at speeds in the range of 15-18 km/s) with an unprecedented high mass resolution of up to 150 000 m/Δm (at m/z 19 for a 500 ms signal duration). The results will be implemented in the LILBID database and will be useful for the calibration and future data interpretation of the Europa Clipper's SUrface Dust Analyzer (SUDA), which will characterize the habitability of Jupiter's icy moon Europa.
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Affiliation(s)
- Arnaud Sanderink
- Laboratoire de Physique et Chimie de l'environnement et de l'Espace, UMR-CNRS 7328, 45071 Orléans, France.,Institute of Geological Sciences, Freie Universität Berlin, 12249 Berlin, Germany
| | - Fabian Klenner
- Institute of Geological Sciences, Freie Universität Berlin, 12249 Berlin, Germany
| | - Illia Zymak
- ELI-Beamlines, 252 41 Dolní Břežany, Czech Republic
| | - Jan Žabka
- J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, 182 00 Prague 8, Czech Republic
| | - Frank Postberg
- Institute of Geological Sciences, Freie Universität Berlin, 12249 Berlin, Germany
| | - Jean-Pierre Lebreton
- Laboratoire de Physique et Chimie de l'environnement et de l'Espace, UMR-CNRS 7328, 45071 Orléans, France
| | - Bertrand Gaubicher
- Laboratoire de Physique et Chimie de l'environnement et de l'Espace, UMR-CNRS 7328, 45071 Orléans, France
| | - Ales Charvat
- Institute of Chemical Technology, University Leipzig, 04103 Leipzig, Germany
| | - Bernd Abel
- Institute of Chemical Technology, University Leipzig, 04103 Leipzig, Germany
| | - Miroslav Polášek
- J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, 182 00 Prague 8, Czech Republic
| | - Barnabé Cherville
- Laboratoire de Physique et Chimie de l'environnement et de l'Espace, UMR-CNRS 7328, 45071 Orléans, France
| | - Laurent Thirkell
- Laboratoire de Physique et Chimie de l'environnement et de l'Espace, UMR-CNRS 7328, 45071 Orléans, France
| | - Christelle Briois
- Laboratoire de Physique et Chimie de l'environnement et de l'Espace, UMR-CNRS 7328, 45071 Orléans, France
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4
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Spectroscopic Detection of Biosignatures in Natural Ice Samples as a Proxy for Icy Moons. Life (Basel) 2023; 13:life13020478. [PMID: 36836835 PMCID: PMC9960113 DOI: 10.3390/life13020478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 01/29/2023] [Accepted: 02/04/2023] [Indexed: 02/11/2023] Open
Abstract
Some of the icy moons of the solar system with a subsurface ocean, such as Europa and Enceladus, are the targets of future space missions that search for potential extraterrestrial life forms. While the ice shells that envelop these moons have been studied by several spacecrafts, the oceans beneath them remain unreachable. To better constrain the habitability conditions of these moons, we must understand the interactions between their frozen crusts, liquid layers, and silicate mantles. To that end, astrobiologists rely on planetary field analogues, for which the polar regions of Earth have proven to be great candidates. This review shows how spectroscopy is a powerful tool in space missions to detect potential biosignatures, in particular on the aforementioned moons, and how the polar regions of the Earth are being used as planetary field analogues for these extra-terrestrial environments.
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5
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Mauceri S, Lee J, Wronkiewicz M, Mandrake L, Doran G, Lightholder J, Cieslarova Z, Kok M, Mora MF, Noell A. Autonomous CE Mass-Spectra Examination for the Ocean Worlds Life Surveyor. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2022; 9:e2022EA002247. [PMID: 36588670 PMCID: PMC9787773 DOI: 10.1029/2022ea002247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 09/15/2022] [Accepted: 09/20/2022] [Indexed: 06/17/2023]
Abstract
Ocean worlds such as Europa and Enceladus are high priority targets in the search for past or extant life beyond Earth. Evidence of life may be preserved in samples of surface ice by processes such as deposition from active plumes, hydrofracturing, or thermal convection. Terrestrial life produces unique distributions of organic molecules that translate into recognizable biosignatures. Identification and quantification of these organic compounds can be achieved by separation science such as capillary electrophoresis coupled to mass spectrometry (CE-MS). However, the data generated by such an instrument can be multiple orders of magnitude larger than what can be transmitted back to Earth during an ocean world's mission. This requires onboard science data analysis capabilities that summarize and prioritize CE-MS observations with limited computational resources. In response, the autonomous capillary electrophoresis mass-spectra examination (ACME) onboard science autonomy system was created for application to the ocean world's life surveyor (OWLS) instrument suite. ACME is able to compress raw mass spectra by two to three orders of magnitude while preserving most of its scientifically relevant information content. This summarization is achieved by the extraction of raw data surrounding autonomously identified ion peaks and the detection and parameterization of unique background regions. Prioritization of the summarized observations is then enabled by providing estimates of scientific utility, including presence of key target compounds, and the uniqueness of an observation relative to previous observations.
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Affiliation(s)
- Steffen Mauceri
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jake Lee
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Mark Wronkiewicz
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Lukas Mandrake
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Gary Doran
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jack Lightholder
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Zuzana Cieslarova
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Miranda Kok
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Maria F. Mora
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Aaron Noell
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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6
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Afzal SS, Akbar W, Rodriguez O, Doumet M, Ha U, Ghaffarivardavagh R, Adib F. Battery-free wireless imaging of underwater environments. Nat Commun 2022; 13:5546. [PMID: 36163186 PMCID: PMC9512789 DOI: 10.1038/s41467-022-33223-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 09/02/2022] [Indexed: 12/04/2022] Open
Abstract
Imaging underwater environments is of great importance to marine sciences, sustainability, climatology, defense, robotics, geology, space exploration, and food security. Despite advances in underwater imaging, most of the ocean and marine organisms remain unobserved and undiscovered. Existing methods for underwater imaging are unsuitable for scalable, long-term, in situ observations because they require tethering for power and communication. Here we describe underwater backscatter imaging, a method for scalable, real-time wireless imaging of underwater environments using fully-submerged battery-free cameras. The cameras power up from harvested acoustic energy, capture color images using ultra-low-power active illumination and a monochrome image sensor, and communicate wirelessly at net-zero-power via acoustic backscatter. We demonstrate wireless battery-free imaging of animals, plants, pollutants, and localization tags in enclosed and open-water environments. The method’s self-sustaining nature makes it desirable for massive, continuous, and long-term ocean deployments with many applications including marine life discovery, submarine surveillance, and underwater climate change monitoring. The authors present an approach to underwater imaging, which does not require tethering or batteries. The low-power camera uses power from harvested acoustic energy and communicates colour images wirelessly via acoustic backscatter.
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Affiliation(s)
- Sayed Saad Afzal
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Waleed Akbar
- MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,Program in Media Arts and Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Osvy Rodriguez
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Mario Doumet
- MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Unsoo Ha
- MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | | | - Fadel Adib
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA. .,MIT Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA. .,Program in Media Arts and Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA. .,MIT Sea Grant, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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7
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Van Volkenburg T, Benzing JS, Craft KL, Ohiri K, Kilhefner A, Irons K, Bradburne C. Microfluidic Chromatography for Enhanced Amino Acid Detection at Ocean Worlds. ASTROBIOLOGY 2022; 22:1116-1128. [PMID: 35984944 PMCID: PMC9508454 DOI: 10.1089/ast.2021.0182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 04/18/2022] [Indexed: 06/15/2023]
Abstract
Increasing interest in the detection of biogenic signatures, such as amino acids, on icy moons and bodies within our solar system has led to the development of compact in situ instruments. Given the expected dilute biosignatures and high salinities of these extreme environments, purification of icy samples before analysis enables increased detection sensitivity. Herein, we outline a novel compact cation exchange method to desalinate proteinogenic amino acids in solution, independent of the type and concentration of salts in the sample. Using a modular microfluidic device, initial experiments explored operational limits of binding capacity with phenylalanine and three model cations, Na+, Mg2+, and Ca2+. Phenylalanine recovery (94-17%) with reduced conductivity (30-200 times) was seen at high salt-to-amino-acid ratios between 25:1 and 500:1. Later experiments tested competition between mixtures of 17 amino acids and other chemistries present in a terrestrial ocean sample. Recoveries ranged from 11% to 85% depending on side chain chemistry and cation competition, with concentration shown for select high affinity amino acids. This work outlines a nondestructive amino acid purification device capable of coupling to multiple downstream analytical techniques for improved characterization of icy samples at remote ocean worlds.
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Affiliation(s)
| | | | - Kathleen L. Craft
- Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA
| | - Korine Ohiri
- Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA
| | - Ashley Kilhefner
- Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA
| | - Kristen Irons
- University of North Carolina at Chapel Hill College of Arts and Sciences, Chapel Hill, North Carolina, USA
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8
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Abstract
As the most volcanically active celestial body in the Solar System, Io is a natural satellite of Jupiter due to its proximity to the planet and the fact that it is in mean motion resonance, known as the Laplace resonance, with the natural satellites Europa and Ganymede. This natural satellite is a good candidate to be visited by future missions. In this sense, the present work has the goal of studying and mapping the best initial orbital conditions for orbits around Io, considering the symmetrical or asymmetical perturbative effects of a third body (Jupiter) and the J2 term from the mass configuration of Io. The initial orbital parameters of the probe were investigated through a set of numerical simulations. The results showed that although most orbits around Io have lifetimes of less than 6 months, some regions were found where the initial conditions of the orbits provided satisfactory times for the accomplishment of future missions around Io.
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9
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Leonard EJ, Howell SM, Mills A, Senske DA, Patthoff DA, Hay HCFC, Pappalardo RT. Finding Order in Chaos: Quantitative Predictors of Chaos Terrain Morphology on Europa. GEOPHYSICAL RESEARCH LETTERS 2022; 49:e2021GL097309. [PMID: 35866056 PMCID: PMC9287068 DOI: 10.1029/2021gl097309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 03/23/2022] [Accepted: 03/28/2022] [Indexed: 06/15/2023]
Abstract
The mechanisms for chaos terrain formation on Europa have long been a source of debate in the scientific community. There exist numerous theoretical and numerical models for chaos formation, but to date there has been a lack of quantifiable observations that can be used to constrain models and permit comparison to the outputs of these chaos models. Here, we use mapping and statistical analysis to develop a quantitative description of chaos terrain and their observed morphologies. For nine chaos features, we map every block, or region of pre-existing terrain within disrupted matrix. We demonstrate that chaos terrains follow a continuous spectrum of morphologies between two endmembers, platy and knobby. We find that any given chaos terrain's morphology can be quantified by means of the linearized exponential slope of its cumulative block area distribution. This quantitative metric provides a new diagnostic parameter in future studies of chaos terrain formation and comparison.
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Affiliation(s)
- E. J. Leonard
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - S. M. Howell
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - A. Mills
- University of AlabamaTuscaloosaALUSA
| | - D. A. Senske
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - H. C. F. C. Hay
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - R. T. Pappalardo
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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10
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The 3D Direct Simulation Monte Carlo Study of Europa’s Gas Plume. UNIVERSE 2022. [DOI: 10.3390/universe8050261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Europa has been spotted as having water outgassing activities by space- and ground-based telescopes as well as reanalysis of the Galileo data. We adopt a 3D Direct Simulation Monte Carlo (DSMC) model to investigate the observed plume characteristics of Europa assuming that supersonic expansion originated from the subsurface vent. With a parametric study of the total gas production rate and initial gas bulk velocity, the gas number density, temperature and velocity information of the outgassing plumes from various case studies were derived. Our results show that the plume gases experience acceleration through mutual collisions and adiabatic cooling when exiting from the surface. The central part of the plume with relatively large gas production rates (1029 and 1030 H2O s−1) was found to sustain thermal equilibrium and near continuum condition. Column density maps integrated along two different viewing angles are presented to demonstrate the importance of the projection effect on remote sensing diagnostics. Finally, the density profiles at different altitudes are provided to prepare for observations of Europa’s plumes including upcoming spacecraft missions such as JUICE and Europa Clipper.
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11
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Touchette D, Altshuler I, Raymond-Bouchard I, Fernández-Martínez MÁ, Bourdages LJ, O'Connor B, Ricco AJ, Whyte LG. Microfluidics Microbial Activity MicroAssay: An Automated In Situ Microbial Metabolic Detection System. ASTROBIOLOGY 2022; 22:158-170. [PMID: 35049343 DOI: 10.1089/ast.2021.0072] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
With no direct extant-life detection instrumentation included in a space mission since the 1970s, the advancement of new technologies to be included in future space missions is imperative. We developed, optimized, and tested a semi-automated prototype, the microfluidics Microbial Activity MicroAssay (μMAMA). This system metabolically characterizes and detects extant microbial life by way of metabolism-indicator redox dyes. We first evaluated the robustness and sensitivity of six redox dye/buffer combinations, and we then tested their responses to metabolic activity in astrobiological analog high-Arctic samples. We determined that the Biolog Inoculating Fluid (IF)-C and AlamarBlue buffered in IF-0a (aB-IF0a) dye/buffer combinations were optimal, as they detected metabolic activity from the fewest microbial cells (102 cells/mL) while maintaining efficacy over a broad physiochemical range of pH (0-13), temperature (-10°C to 37°C), salinity and perchlorate (tested up to 30%), and in the presence of a Mars regolith simulant (MMS-2). The μMAMA, which incorporated these redox dyes, detected extant active cold-adapted microbial life from high Arctic analog sites, including samples amended with substrates targeting chemolithoautotrophic metabolisms. Given μMAMA's small size (we estimate a complete planetary instrument could occupy as little as 3 L) and potential for automation, it could easily be incorporated into almost any landed platform for life detection missions.
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Affiliation(s)
- David Touchette
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- McGill Space Institute, Montréal, Québec, Canada
| | - Ianina Altshuler
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- Department of Animal and Aquaculture Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
| | - Isabelle Raymond-Bouchard
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- McGill Space Institute, Montréal, Québec, Canada
| | - Miguel Ángel Fernández-Martínez
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- McGill Space Institute, Montréal, Québec, Canada
| | - Louis-Jacques Bourdages
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- Department of Mechanical Engineering, Faculty of Engineering, McGill University, Montréal, Québec, Canada
| | - Brady O'Connor
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- McGill Space Institute, Montréal, Québec, Canada
| | | | - Lyle G Whyte
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- McGill Space Institute, Montréal, Québec, Canada
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12
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Ashkenazy Y, Tziperman E. Dynamic Europa ocean shows transient Taylor columns and convection driven by ice melting and salinity. Nat Commun 2021; 12:6376. [PMID: 34737306 PMCID: PMC8569204 DOI: 10.1038/s41467-021-26710-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 10/19/2021] [Indexed: 11/30/2022] Open
Abstract
The deep (~100 km) ocean of Europa, Jupiter's moon, covered by a thick icy shell, is one of the most probable places in the solar system to find extraterrestrial life. Yet, its ocean dynamics and its interaction with the ice cover have received little attention. Previous studies suggested that Europa's ocean is turbulent using a global model and taking into account non-hydrostatic effects and the full Coriolis force. Here we add critical elements, including consistent top and bottom heating boundary conditions and the effects of icy shell melting and freezing on ocean salinity. We find weak stratification that is dominated by salinity variations. The ocean exhibits strong transient convection, eddies, and zonal jets. Transient motions organize in Taylor columns parallel to Europa's axis of rotation, are static inside of the tangent cylinder and propagate equatorward outside the cylinder. The meridional oceanic heat transport is intense enough to result in a nearly uniform ice thickness, that is expected to be observable in future missions.
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Affiliation(s)
- Yosef Ashkenazy
- Department of Solar Energy and Environmental Physics, The Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Negev, 84990, Israel.
| | - Eli Tziperman
- Department of Earth and Planetary Sciences and School of Engineering and Applied Sciences, Harvard University, 20 Oxford Street, Cambridge, MA, 02138, USA
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13
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Rivera-Valentín EG, Filiberto J, Lynch KL, Mamajanov I, Lyons TW, Schulte M, Méndez A. Introduction-First Billion Years: Habitability. ASTROBIOLOGY 2021; 21:893-905. [PMID: 34406807 PMCID: PMC8403211 DOI: 10.1089/ast.2020.2314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 12/22/2020] [Indexed: 06/13/2023]
Abstract
The physical processes active during the first billion years (FBY) of Earth's history, such as accretion, differentiation, and impact cratering, provide constraints on the initial conditions that were conducive to the formation and establishment of life on Earth. This motivated the Lunar and Planetary Institute's FBY topical initiative, which was a four-part conference series intended to look at each of these physical processes to study the basic structure and composition of our Solar System that was set during the FBY. The FBY Habitability conference, held in September 2019, was the last in this series and was intended to synthesize the initiative; specifically, to further our understanding of the origins of life, planetary and environmental habitability, and the search for life beyond Earth. The conference included discussions of planetary habitability and the potential emergence of life on bodies within our Solar System, as well as extrasolar systems by applying our knowledge of the Solar System's FBY, and in particular Earth's early history. To introduce this Special Collection, which resulted from work discussed at the conference, we provide a review of the main themes and a synopsis of the FBY Habitability conference.
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Affiliation(s)
| | - Justin Filiberto
- Lunar and Planetary Institute, Universities Space Research Association, Houston, Texas, USA
| | - Kennda L. Lynch
- Lunar and Planetary Institute, Universities Space Research Association, Houston, Texas, USA
| | - Irena Mamajanov
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Timothy W. Lyons
- Department of Earth and Planetary Sciences, University of California Riverside, Riverside, California, USA
| | - Mitch Schulte
- Planetary Science Division, NASA Headquarters, Washington, District of Columbia, USA
| | - Abel Méndez
- Planetary Habitability Laboratory, University of Puerto Rico Arecibo, Arecibo, Puerto Rico
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14
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Jaramillo EA, Ferreira Santos MS, Noell AC, Mora MF. Capillary electrophoresis method for analysis of inorganic and organic anions related to habitability and the search for life. Electrophoresis 2021; 42:1956-1964. [PMID: 34287988 DOI: 10.1002/elps.202100134] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 11/08/2022]
Abstract
In situ missions of exploration require analytical methods that are capable of detecting a wide range of molecular targets in complex matrices without a priori assumptions of sample composition. Furthermore, these methods should minimize the number of reagents needed and any sample preparation steps. We have developed a method for the detection of metabolically relevant inorganic and organic anions that is suitable for implementation on in situ spaceflight missions. Using 55 mM acetic acid, 50 mM triethylamine, and 5% glycerol, more than 21 relevant anions are separated in less than 20 min. The method is robust to sample ionic strength, tolerating high concentrations of background salts (up to 900 mM NaCl and 300 mM MgSO4 ). This is an important feature for future missions to ocean worlds. The method was validated using a culture of Escherichia coli and with high salinity natural samples collected from Mono Lake, California.
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Affiliation(s)
| | | | - Aaron C Noell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Maria F Mora
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
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15
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Mudge MC, Nunn BL, Firth E, Ewert M, Hales K, Fondrie WE, Noble WS, Toner J, Light B, Junge KA. Subzero, saline incubations of
Colwellia psychrerythraea
reveal strategies and biomarkers for sustained life in extreme icy environments. Environ Microbiol 2021; 23:3840-3866. [DOI: 10.1111/1462-2920.15485] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/22/2021] [Indexed: 11/26/2022]
Affiliation(s)
- Miranda C. Mudge
- Department of Genome Sciences University of Washington Seattle WA USA
- Department of Molecular and Cellular Biology University of Washington Seattle WA USA
| | - Brook L. Nunn
- Department of Genome Sciences University of Washington Seattle WA USA
- Astrobiology Program University of Washington Seattle WA USA
| | - Erin Firth
- Applied Physics Lab, Polar Science Center University of Washington Seattle WA USA
| | - Marcela Ewert
- Applied Physics Lab, Polar Science Center University of Washington Seattle WA USA
| | - Kianna Hales
- Department of Genome Sciences University of Washington Seattle WA USA
| | | | - William S. Noble
- Department of Genome Sciences University of Washington Seattle WA USA
- Paul G. Allen School of Computer Science and Engineering University of Washington Seattle WA USA
| | - Jonathan Toner
- Department of Earth and Space Sciences University of Washington Seattle WA USA
| | - Bonnie Light
- Applied Physics Lab, Polar Science Center University of Washington Seattle WA USA
| | - Karen A. Junge
- Applied Physics Lab, Polar Science Center University of Washington Seattle WA USA
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16
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Sobrado JM. Mimicking the Martian Hydrological Cycle: A Set-Up to Introduce Liquid Water in Vacuum. SENSORS (BASEL, SWITZERLAND) 2020; 20:E6150. [PMID: 33138024 PMCID: PMC7662484 DOI: 10.3390/s20216150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/25/2020] [Accepted: 10/27/2020] [Indexed: 11/16/2022]
Abstract
Liquid water is well known as the life ingredient as a solvent. However, so far, it has only been found in liquid state on this planetary surface. The aim of this experiment and technological development was to test if a moss sample is capable of surviving in Martian conditions. We built a system that simulates the environmental conditions of the red planet including its hydrological cycle. This laboratory facility enables us to control the water cycle in its three phases through temperature, relative humidity, hydration, and pressure with a system that injects water droplets into a vacuum chamber. We successfully simulated the daytime and nighttime of Mars by recreating water condensation and created a layer of superficial ice that protects the sample against external radiation and minimizes the loss of humidity due to evaporation to maintain a moss sample in survival conditions in this extreme environment. We performed the simulations with the design and development of different tools that recreate Martian weather in the MARTE simulation chamber.
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17
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Cockell CS, McLean CM, Perera L, Aka S, Stevens A, Dickinson AW. Growth of Non-Halophilic Bacteria in the Sodium-Magnesium-Sulfate-Chloride Ion System: Unravelling the Complexities of Ion Interactions in Terrestrial and Extraterrestrial Aqueous Environments. ASTROBIOLOGY 2020; 20:944-955. [PMID: 32434375 DOI: 10.1089/ast.2019.2092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Motivated by an interest in understanding the habitability of aqueous environments on Earth and in extraterrestrial settings, this study investigated the influence of ions in an artificial sodium-magnesium-sulfate-chloride ion system on the growth parameters (lag phase, growth rate, and final cell concentration) of bacteria. These four ions, in different combinations, are key components of many aqueous environments on Earth and elsewhere. We investigated non-halophilic bacteria deliberately to remove the bias of prior adaptations to high concentrations of selected ions so that we could compare the effects of different ions. We tested the hypothesis that water activity determined the growth parameters independent of the ion types. Neither water activity or ionic strength alone could predict growth. However, when ionic strengths were matched, many differences in growth parameters could be explained by the water activity. We suggest that species-specific effects (caused by differences in biochemical and physiological influences), the role of individual ions in cellular processes, and potentially the chaotropicity and kosmotropicity of solutions influenced the growth. Our data show that although extreme combinations of these ions allow for general predictions on the habitability of extraterrestrial aqueous environments, a complex interplay of ionic effects influences the growth and thus the adaptations required for given ion combinations. The data also show that an accurate quantification of the habitability of ocean worlds, such as Europa and Enceladus, can only be made when samples are obtained from these water bodies and the ion combinations are determined.
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Affiliation(s)
- Charles S Cockell
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Claire-Marie McLean
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Liam Perera
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Salomé Aka
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Adam Stevens
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrew W Dickinson
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, United Kingdom
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18
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Schaefer K, Dambuza IM, Dall’Angelo S, Yuecel R, Jaspars M, Trembleau L, Zanda M, Brown GD, Netea MG, Gow NAR. A Weakened Immune Response to Synthetic Exo-Peptides Predicts a Potential Biosecurity Risk in the Retrieval of Exo-Microorganisms. Microorganisms 2020; 8:microorganisms8071066. [PMID: 32708909 PMCID: PMC7409182 DOI: 10.3390/microorganisms8071066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/30/2020] [Accepted: 07/15/2020] [Indexed: 11/25/2022] Open
Abstract
Simple Summary We tested the immune response of T cells of the mammalian immune system towards protein antigens that includes the unusual amino acids isovaline and α-aminoisobutyric. Those amino acids have been found in high abundance on carbonaceous meteorites but are extremely rare in proteomes of earth organisms. We hypothesised that proteins of non-terrestrial alien life forms might contain such amino acids and tested whether chemically synthesised “exopeptides” that contain these amino acids could be detected by the immune system. Our assays, based on the responses of CD8+ T cells to these exopeptides, indicated that antigen cleavage, processing, and subsequent T cell activation still occurred, but were less efficient than the response to control peptides that lacked these amino acids. We therefore speculate that the encounter of putative exo-microorganisms of an unusual antigenic repertoire might pose an immunological risk for space missions aiming to retrieve potentially biotic samples from exoplanets and moons. Abstract The discovery of liquid water at several locations in the solar system raises the possibility that microbial life may have evolved outside Earth and as such could be accidently introduced into the Earth’s ecosystem. Unusual sugars or amino acids, like non-proteinogenic isovaline and α-aminoisobutyric acid that are vanishingly rare or absent from life forms on Earth, have been found in high abundance on non-terrestrial carbonaceous meteorites. It is therefore conceivable that exo-microorganisms might contain proteins that include these rare amino acids. We therefore asked whether the mammalian immune system would be able to recognize and induce appropriate immune responses to putative proteinaceous antigens that include these rare amino acids. To address this, we synthesised peptide antigens based on a backbone of ovalbumin and introduced isovaline and α-aminoisobutyric acid residues and demonstrated that these peptides can promote naïve OT-I cell activation and proliferation, but did so less efficiently than the canonical peptides. This is relevant to the biosecurity of missions that may retrieve samples from exoplanets and moons that have conditions that may be permissive for life, suggesting that accidental contamination and exposure to exo-microorganisms with such distinct proteomes might pose an immunological challenge.
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Affiliation(s)
- Katja Schaefer
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; (I.M.D.); (G.D.B.); (N.A.R.G.)
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
- Correspondence:
| | - Ivy M. Dambuza
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; (I.M.D.); (G.D.B.); (N.A.R.G.)
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Sergio Dall’Angelo
- Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK; (S.D.); (M.Z.)
| | - Raif Yuecel
- Iain Fraser Cytometry Centre (IFCC), University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK;
- Centre for Cytomics, Geoffrey Pope Building, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Marcel Jaspars
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, UK; (M.J.); (L.T.)
| | - Laurent Trembleau
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, UK; (M.J.); (L.T.)
| | - Matteo Zanda
- Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK; (S.D.); (M.Z.)
- Sir David Davies Building, Centre for Imaging Science, School of Science, Loughborough University, Loughborough LE11 3TU, UK
| | - Gordon D. Brown
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; (I.M.D.); (G.D.B.); (N.A.R.G.)
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
| | - Mihai G. Netea
- Department of Internal Medicine, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands;
- Department for Genomics & Immunoregulation, Life and Medical Sciences Institute (LIMES), University of Bonn, 53115 Bonn, Germany
| | - Neil A. R. Gow
- The Aberdeen Fungal Group, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK; (I.M.D.); (G.D.B.); (N.A.R.G.)
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, UK
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19
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On A Hypothetical Mechanism of Interstellar Life Transfer Trough Nomadic Objects. ORIGINS LIFE EVOL B 2020; 50:87-96. [PMID: 32034615 DOI: 10.1007/s11084-020-09591-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/03/2020] [Indexed: 10/25/2022]
Abstract
Lethal radiation, low vacuum pressure and low temperatures - this is how space welcomes organisms. Crossing of immense interstellar distances inflates the exposure time of biological material to harmful space conditions. This paper discusses the intriguing possibility of a life-bearing exoplanet being ejected from its planetary system and carrying life across interstellar distances (nomadic = free floating = rogue planet). The proposed interstellar panspermia mechanism reduces the exposure time to space conditions and provides multiple chances for interactions between microbes-bearing rock debris and exoplanets within system the nomadic object encountered on its way. The testing strategy is outlined and discussed in the paper, including testable predictions the proposed hypothesis makes.
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20
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Martin KP, MacKenzie SM, Barnes JW, Ytreberg FM. Protein Stability in Titan's Subsurface Water Ocean. ASTROBIOLOGY 2020; 20:190-198. [PMID: 31730377 PMCID: PMC7041334 DOI: 10.1089/ast.2018.1972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 10/08/2019] [Indexed: 06/10/2023]
Abstract
Models of Titan predict that there is a subsurface ocean of water and ammonia under a layer of ice. Such an ocean would be important in the search for extraterrestrial life since it provides a potentially habitable environment. To evaluate how Earth-based proteins would behave in Titan's subsurface ocean environment, we used molecular dynamics simulations to calculate the properties of proteins with the most common secondary structure types (alpha helix and beta sheet) in both Earth and Titan-like conditions. The Titan environment was simulated by using a temperature of 300 K, a pressure of 1000 bar, and a eutectic mixture of water and ammonia. We analyzed protein compactness, flexibility, and backbone dihedral distributions to identify differences between the two environments. Secondary structures in the Titan environment were found to be less long-lasting, less flexible, and had small differences in backbone dihedral preferences (e.g., in one instance a pi helix formed). These environment-driven differences could lead to changes in how these proteins interact with other biomolecules and therefore changes in how evolution would potentially shape proteins to function in subsurface ocean environments.
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Affiliation(s)
- Kyle P. Martin
- Department of Physics, University of Idaho, Moscow, Idaho
- Institute for Modeling Collaboration and Innovation, University of Idaho, Moscow, Idaho
| | | | | | - F. Marty Ytreberg
- Department of Physics, University of Idaho, Moscow, Idaho
- Institute for Modeling Collaboration and Innovation, University of Idaho, Moscow, Idaho
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21
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Thomson SD, Quinn RC, Ricco AJ, Koehne JE. Electrochemistry for Life Detection on Ocean Worlds. ChemElectroChem 2020. [DOI: 10.1002/celc.201901683] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Seamus D. Thomson
- NASA Postdoctoral ProgramNASA Ames Research Center Moffett Field, California 94035 USA
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22
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Netea MG, Domínguez-Andrés J, Eleveld M, op den Camp HJM, van der Meer JWM, Gow NAR, de Jonge MI. Immune recognition of putative alien microbial structures: Host-pathogen interactions in the age of space travel. PLoS Pathog 2020; 16:e1008153. [PMID: 31999804 PMCID: PMC6991955 DOI: 10.1371/journal.ppat.1008153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human space travel is on the verge of visiting Mars and, in the future, even more distant places in the solar system. These journeys will be also made by terrestrial microorganisms (hitchhiking on the bodies of astronauts or on scientific instruments) that, upon arrival, will come into contact with new planetary environments, despite the best measures to prevent contamination. These microorganisms could potentially adapt and grow in the new environments and subsequently recolonize and infect astronauts. An even more challenging situation would be if truly alien microorganisms will be present on these solar system bodies: What will be their pathogenic potential, and how would our immune host defenses react? It will be crucial to anticipate these situations and investigate how the immune system of humans might cope with modified terrestrial or alien microbes. We propose several scenarios that may be encountered and how to respond to these challenges.
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Affiliation(s)
- Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
- Department for Genomics & Immunoregulation, Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Jorge Domínguez-Andrés
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Marc Eleveld
- Department of Laboratory Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Huub J. M. op den Camp
- Department of Microbiology, Faculty of Science, Radboud University, Nijmegen, the Netherlands
| | - Jos W. M. van der Meer
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Neil A. R. Gow
- School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Marien I. de Jonge
- Department of Laboratory Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
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23
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Ashkenazy Y. The surface temperature of Europa. Heliyon 2019; 5:e01908. [PMID: 31294099 PMCID: PMC6595243 DOI: 10.1016/j.heliyon.2019.e01908] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 03/10/2019] [Accepted: 06/03/2019] [Indexed: 11/01/2022] Open
Abstract
Previous estimates of the annual mean surface temperature of Jupiter's moon, Europa, neglected the effect of the eccentricity of Jupiter's orbit around the Sun, the effect of the emissivity and heat capacity of Europa's ice, the effect of the eclipse of Europa (i.e., the relative time that Europa is within the shadow of Jupiter), the effect of Jupiter's radiation, and the effect of Europa's internal heating. Other studies concentrated on the diurnal cycle but neglected some of the above factors. In addition, to our knowledge, the seasonal cycle of the surface temperature of Europa was not estimated. Here we systematically estimate the diurnal, seasonal and annual mean surface temperature of Europa, when Europa's obliquity, emissivity, heat capacity, and eclipse, as well as Jupiter's radiation, internal heating, and eccentricity, are all taken into account. For a typical internal heating rate of 0.05 W m - 2 , the equator, pole, and the global and mean annual mean surface temperatures are 96 K, 46 K, and 90 K, respectively. We found that the temperature at the high latitudes is significantly affected by the internal heating, especially during the winter solstice, suggesting that measurements of high latitude surface temperatures can be used to constrain the internal heating. We also estimate the incoming solar radiation to Enceladus, the moon of Saturn.
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Affiliation(s)
- Yosef Ashkenazy
- Department of Solar Energy and Environmental Physics, BIDR, Ben-Gurion University, Midreshet Ben-Gurion, Israel
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24
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Ward LM, Stamenković V, Hand K, Fischer WW. Follow the Oxygen: Comparative Histories of Planetary Oxygenation and Opportunities for Aerobic Life. ASTROBIOLOGY 2019; 19:811-824. [PMID: 31188035 DOI: 10.1089/ast.2017.1779] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Aerobic respiration-the reduction of molecular oxygen (O2) coupled to the oxidation of reduced compounds such as organic carbon, ferrous iron, reduced sulfur compounds, or molecular hydrogen while conserving energy to drive cellular processes-is the most widespread and bioenergetically favorable metabolism on Earth today. Aerobic respiration is essential for the development of complex multicellular life; thus the presence of abundant O2 is an important metric for planetary habitability. O2 on Earth is supplied by oxygenic photosynthesis, but it is becoming more widely understood that abiotic processes may supply meaningful amounts of O2 on other worlds. The modern atmosphere and rock record of Mars suggest a history of relatively high O2 as a result of photochemical processes, potentially overlapping with the range of O2 concentrations used by biology. Europa may have accumulated high O2 concentrations in its subsurface ocean due to the radiolysis of water ice at its surface. Recent modeling efforts suggest that coexisting water and O2 may be common on exoplanets, with confirmation from measurements of exoplanet atmospheres potentially coming soon. In all these cases, O2 accumulates through abiotic processes-independent of water-oxidizing photosynthesis. We hypothesize that abiogenic O2 may enhance the habitability of some planetary environments, allowing highly energetic aerobic respiration and potentially even the development of complex multicellular life which depends on it, without the need to first evolve oxygenic photosynthesis. This hypothesis is testable with further exploration and life-detection efforts on O2-rich worlds such as Mars and Europa, and comparison to O2-poor worlds such as Enceladus. This hypothesis further suggests a new dimension to planetary habitability: "Follow the Oxygen," in which environments with opportunities for energy-rich metabolisms such as aerobic respiration are preferentially targeted for investigation and life detection.
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Affiliation(s)
- Lewis M Ward
- 1 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
| | - Vlada Stamenković
- 2 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Kevin Hand
- 2 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Woodward W Fischer
- 1 Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
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25
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Blanco Y, de Diego-Castilla G, Viúdez-Moreiras D, Cavalcante-Silva E, Rodríguez-Manfredi JA, Davila AF, McKay CP, Parro V. Effects of Gamma and Electron Radiation on the Structural Integrity of Organic Molecules and Macromolecular Biomarkers Measured by Microarray Immunoassays and Their Astrobiological Implications. ASTROBIOLOGY 2018; 18:1497-1516. [PMID: 30070898 PMCID: PMC6276817 DOI: 10.1089/ast.2016.1645] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 04/10/2018] [Indexed: 05/20/2023]
Abstract
High-energy ionizing radiation in the form of solar energetic particles and galactic cosmic rays is pervasive on the surface of planetary bodies with thin atmospheres or in space facilities for humans, and it may seriously affect the chemistry and the structure of organic and biological material. We used fluorescent microarray immunoassays to assess how different doses of electron and gamma radiations affect the stability of target compounds such as biological polymers and small molecules (haptens) conjugated to large proteins. The radiation effect was monitored by measuring the loss in the immunoidentification of the target due to an impaired ability of the antibodies for binding their corresponding irradiated and damaged epitopes (the part of the target molecule to which antibodies bind). Exposure to electron radiation alone was more damaging at low doses (1 kGy) than exposure to gamma radiation alone, but this effect was reversed at the highest radiation dose (500 kGy). Differences in the dose-effect immunoidentification patterns suggested that the amount (dose) and not the type of radiation was the main factor for the cumulative damage on the majority of the assayed molecules. Molecules irradiated with both types of radiation showed a response similar to that of the individual treatments at increasing radiation doses, although the pattern obtained with electrons only was the most similar. The calculated radiolysis constant did not show a unique pattern; it rather suggested a different behavior perhaps associated with the unique structure of each molecule. Although not strictly comparable with extraterrestrial conditions because the irradiations were performed under air and at room temperature, our results may contribute to understanding the effects of ionizing radiation on complex molecules and the search for biomarkers through bioaffinity-based systems in planetary exploration.
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Affiliation(s)
- Yolanda Blanco
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | - Graciela de Diego-Castilla
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | - Daniel Viúdez-Moreiras
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | - Erika Cavalcante-Silva
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
| | | | - Alfonso F. Davila
- Space Science Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Christopher P. McKay
- Space Science Division, NASA Ames Research Center, Moffett Field, California, USA
| | - Victor Parro
- Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Torrejón de Ardoz, Madrid, Spain
- Address correspondence to: Victor Parro, Department of Molecular Evolution, Centro de Astrobiología (INTA-CSIC), Carretera de Ajalvir km 4, Torrejón de Ardoz, Madrid 28850, Spain
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26
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Creamer JS, Mora MF, Willis PA. Stability of reagents used for chiral amino acid analysis during spaceflight missions in high‐radiation environments. Electrophoresis 2018; 39:2864-2871. [DOI: 10.1002/elps.201800274] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/28/2018] [Accepted: 08/29/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Jessica S. Creamer
- Jet Propulsion LaboratoryCalifornia Institute of Technology Pasadena CA USA
| | - Maria F. Mora
- Jet Propulsion LaboratoryCalifornia Institute of Technology Pasadena CA USA
| | - Peter A. Willis
- Jet Propulsion LaboratoryCalifornia Institute of Technology Pasadena CA USA
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27
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Trivedi CB, Lau GE, Grasby SE, Templeton AS, Spear JR. Low-Temperature Sulfidic-Ice Microbial Communities, Borup Fiord Pass, Canadian High Arctic. Front Microbiol 2018; 9:1622. [PMID: 30087659 PMCID: PMC6066561 DOI: 10.3389/fmicb.2018.01622] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 06/28/2018] [Indexed: 11/30/2022] Open
Abstract
A sulfur-dominated supraglacial spring system found at Borup Fiord Pass (BFP), Ellesmere Island, Nunavut, Canada, is a unique sulfur-on-ice system expressed along the toe of a glacier. BFP has an intermittent flowing, subsurface-derived, glacial spring that creates a large white-yellow icing (aufeis) that extends down-valley. Over field campaigns in 2014, 2016, and 2017, numerous samples were collected and analyzed for both microbial community composition and aqueous geochemistry. Samples were collected from multiple site types: spring discharge fluid, aufeis (spring-derived ice), melt pools with sedimented cryoconite material, and mineral precipitate scrapings, to probe how microbial communities differed between site types in a dynamic freeze/thaw sulfur-rich system. Dissolved sulfate varied between 0.07 and 11.6 mM and was correlated with chloride concentrations, where the fluids were saltiest among spring fluids. The highest sulfate samples exhibited high dissolved sulfide values between 0.22 and 2.25 mM. 16S rRNA gene sequencing from melt pool and aufeis samples from the 2014 campaign were highly abundant in operational taxonomic units (OTUs) closely related to sulfur-oxidizing microorganisms (SOM; Sulfurimonas, Sulfurovum, and Sulfuricurvum). Subsequent sampling 2 weeks later had fewer SOMs and showed an increased abundance of the genus Flavobacterium. Desulfocapsa, an organism that specializes in the disproportionation of inorganic sulfur compounds was also found. Samples from 2016 and 2017 revealed that microorganisms present were highly similar in community composition to 2014 samples, primarily echoed by the continued presence of Flavobacterium sp. Results suggest that while there may be acute events where sulfur cycling organisms dominate, a basal community structure appears to dominate over time and site type. These results further enhance our knowledge of low-temperature sulfur systems on Earth, and help to guide the search for potential life on extraterrestrial worlds, such as Europa, where similar low-temperature sulfur-rich conditions may exist.
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Affiliation(s)
- Christopher B. Trivedi
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, United States
| | - Graham E. Lau
- Department of Geological Sciences, University of Colorado Boulder, Boulder, CO, United States
| | | | - Alexis S. Templeton
- Department of Geological Sciences, University of Colorado Boulder, Boulder, CO, United States
| | - John R. Spear
- Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, United States
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Sephton MA, Waite JH, Brockwell TG. How to Detect Life on Icy Moons. ASTROBIOLOGY 2018; 18:843-855. [PMID: 30035638 PMCID: PMC6067095 DOI: 10.1089/ast.2017.1656] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 12/10/2017] [Indexed: 05/09/2023]
Abstract
The icy moons of the outer Solar System present the possibility of subsurface water, habitable conditions, and potential abodes for life. Access to evidence that reveals the presence of life on the icy moons can be facilitated by plumes that eject material from the subsurface out into space. One instrument capable of performing life-search investigations at the icy moons is the MAss SPectrometer for Planetary EXploration/Europa (MASPEX), which constitutes a high-resolution, high-sensitivity multibounce time-of-flight mass spectrometer capable of measuring trace amounts (ppb) of organic compounds. MASPEX has been selected for the NASA Europa Clipper mission and will sample any plumes and the surface-sputtered atmosphere to assess any evidence for habitability and life. MASPEX is capable of similar investigations targeted at other icy moons. Data may be forthcoming from direct sampling but also impact dissociation because of the high speed of some analytes. Impact dissociation is analogous to the dissociation provided by modern analytical pyrolysis methods. Radiolytic dissociation on the europan surface before or during the sputtering process can also induce fragmentation similar to pyrolysis. In this study, we have compiled pyrolysis mass spectrometry data from a variety of biological and nonbiological materials to demonstrate the ability of MASPEX to recognize habitability and detect life in any plumes and atmospheres of icy moons. Key Words: Europa-Icy moons-Life detection-Mass spectrometry-Organic matter. Astrobiology 18, 843-855.
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Affiliation(s)
- Mark A. Sephton
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, United Kingdom
| | - Jack Hunter Waite
- Space Science and Engineering Division, Southwest Research Institute, San Antonio, Texas
| | - Tim G. Brockwell
- Space Science and Engineering Division, Southwest Research Institute, San Antonio, Texas
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Arney G, Domagal-Goldman SD, Meadows VS. Organic Haze as a Biosignature in Anoxic Earth-like Atmospheres. ASTROBIOLOGY 2018; 18:311-329. [PMID: 29189040 PMCID: PMC5867516 DOI: 10.1089/ast.2017.1666] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 09/20/2017] [Indexed: 05/21/2023]
Abstract
Early Earth may have hosted a biologically mediated global organic haze during the Archean eon (3.8-2.5 billion years ago). This haze would have significantly impacted multiple aspects of our planet, including its potential for habitability and its spectral appearance. Here, we model worlds with Archean-like levels of carbon dioxide orbiting the ancient Sun and an M4V dwarf (GJ 876) and show that organic haze formation requires methane fluxes consistent with estimated Earth-like biological production rates. On planets with high fluxes of biogenic organic sulfur gases (CS2, OCS, CH3SH, and CH3SCH3), photochemistry involving these gases can drive haze formation at lower CH4/CO2 ratios than methane photochemistry alone. For a planet orbiting the Sun, at 30× the modern organic sulfur gas flux, haze forms at a CH4/CO2 ratio 20% lower than at 1× the modern organic sulfur flux. For a planet orbiting the M4V star, the impact of organic sulfur gases is more pronounced: at 1× the modern Earth organic sulfur flux, a substantial haze forms at CH4/CO2 ∼ 0.2, but at 30× the organic sulfur flux, the CH4/CO2 ratio needed to form haze decreases by a full order of magnitude. Detection of haze at an anomalously low CH4/CO2 ratio could suggest the influence of these biogenic sulfur gases and therefore imply biological activity on an exoplanet. When these organic sulfur gases are not readily detectable in the spectrum of an Earth-like exoplanet, the thick organic haze they can help produce creates a very strong absorption feature at UV-blue wavelengths detectable in reflected light at a spectral resolution as low as 10. In direct imaging, constraining CH4 and CO2 concentrations will require higher spectral resolution, and R > 170 is needed to accurately resolve the structure of the CO2 feature at 1.57 μm, likely the most accessible CO2 feature on an Archean-like exoplanet. Key Words: Organic haze-Organic sulfur gases-Biosignatures-Archean Earth. Astrobiology 18, 311-329.
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Affiliation(s)
- Giada Arney
- NASA Goddard Space Flight Center, Greenbelt, Maryland
- NASA Astrobiology Institute Virtual Planetary Laboratory, University of Washington, Seattle, Washington
| | - Shawn D. Domagal-Goldman
- NASA Goddard Space Flight Center, Greenbelt, Maryland
- NASA Astrobiology Institute Virtual Planetary Laboratory, University of Washington, Seattle, Washington
| | - Victoria S. Meadows
- NASA Astrobiology Institute Virtual Planetary Laboratory, University of Washington, Seattle, Washington
- Astronomy Department, University of Washington, Seattle, Washington
- University of Washington Astrobiology Program, Seattle, Washington
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Serabyn E, Liewer K, Wallace JK. Resolution optimization of an off-axis lensless digital holographic microscope. APPLIED OPTICS 2018; 57:A172-A180. [PMID: 29328143 DOI: 10.1364/ao.57.00a172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/28/2017] [Indexed: 06/07/2023]
Abstract
Microscopes aimed at detecting cellular life in extreme environments such as ocean-bearing solar system moons must provide high resolution in a compact, robust instrument. Here, we consider the resolution optimization of a compact off-axis lensless digital holographic microscope (DHM) that consists of a sample placed between an input point-source pair and a detector array. Two optimal high-resolution regimes are identified at opposite extremes-a low-magnification regime with the sample located near a small-pixel detector array, and a high-magnification regime with the sample near the input plane. In the former, resolution improves with smaller pixels, while in the latter, the effect of the finite pixel size is obviated, and the spatial resolution improves with detector array size. Using an off-axis lensless DHM with a 2 k×2 k array of 5.5 μm-pixels in the high-magnification regime, and standard aberration correction software, a resolution of ∼0.95 μm has been demonstrated, a factor of 5.8 smaller than the pixel size. Our analysis further suggests that with yet larger detector arrays, a lensless DHM should be capable of near wavelength-scale resolution.
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P-Adic Analog of Navier–Stokes Equations: Dynamics of Fluid’s Flow in Percolation Networks (from Discrete Dynamics with Hierarchic Interactions to Continuous Universal Scaling Model). ENTROPY 2017. [DOI: 10.3390/e19040161] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Nadeau J, Lindensmith C, Deming JW, Fernandez VI, Stocker R. Microbial Morphology and Motility as Biosignatures for Outer Planet Missions. ASTROBIOLOGY 2016; 16:755-774. [PMID: 27552160 PMCID: PMC5069736 DOI: 10.1089/ast.2015.1376] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 06/13/2016] [Indexed: 05/23/2023]
Abstract
Meaningful motion is an unambiguous biosignature, but because life in the Solar System is most likely to be microbial, the question is whether such motion may be detected effectively on the micrometer scale. Recent results on microbial motility in various Earth environments have provided insight into the physics and biology that determine whether and how microorganisms as small as bacteria and archaea swim, under which conditions, and at which speeds. These discoveries have not yet been reviewed in an astrobiological context. This paper discusses these findings in the context of Earth analog environments and environments expected to be encountered in the outer Solar System, particularly the jovian and saturnian moons. We also review the imaging technologies capable of recording motility of submicrometer-sized organisms and discuss how an instrument would interface with several types of sample-collection strategies. Key Words: In situ measurement-Biosignatures-Microbiology-Europa-Ice. Astrobiology 16, 755-774.
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Affiliation(s)
- Jay Nadeau
- 1 GALCIT, California Institute of Technology , Pasadena, California
| | - Chris Lindensmith
- 2 Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California
| | - Jody W Deming
- 3 Department of Biological Oceanography, University of Washington , Seattle, Washington
| | - Vicente I Fernandez
- 4 Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts
| | - Roman Stocker
- 4 Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts
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Taubner RS, Schleper C, Firneis MG, Rittmann SKMR. Assessing the Ecophysiology of Methanogens in the Context of Recent Astrobiological and Planetological Studies. Life (Basel) 2015; 5:1652-86. [PMID: 26703739 PMCID: PMC4695842 DOI: 10.3390/life5041652] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 10/15/2015] [Accepted: 11/10/2015] [Indexed: 12/31/2022] Open
Abstract
Among all known microbes capable of thriving under extreme and, therefore, potentially extraterrestrial environmental conditions, methanogens from the domain Archaea are intriguing organisms. This is due to their broad metabolic versatility, enormous diversity, and ability to grow under extreme environmental conditions. Several studies revealed that growth conditions of methanogens are compatible with environmental conditions on extraterrestrial bodies throughout the Solar System. Hence, life in the Solar System might not be limited to the classical habitable zone. In this contribution we assess the main ecophysiological characteristics of methanogens and compare these to the environmental conditions of putative habitats in the Solar System, in particular Mars and icy moons. Eventually, we give an outlook on the feasibility and the necessity of future astrobiological studies concerning methanogens.
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Affiliation(s)
- Ruth-Sophie Taubner
- Research Platform: ExoLife, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
- Institute of Astrophysics, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
| | - Christa Schleper
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria.
| | - Maria G Firneis
- Research Platform: ExoLife, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
- Institute of Astrophysics, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
| | - Simon K-M R Rittmann
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria.
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Palomba E, Longobardo A, Dirri F, Zampetti E, Biondi D, Saggin B, Bearzotti A, Macagnano A. VISTA: A μ-Thermogravimeter for Investigation of Volatile Compounds in Planetary Environments. ORIGINS LIFE EVOL B 2015; 46:273-81. [PMID: 26603435 DOI: 10.1007/s11084-015-9473-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Accepted: 07/15/2015] [Indexed: 11/29/2022]
Abstract
This paper presents the VISTA (Volatile In Situ Thermogravimetry Analyser) instrument, conceived to perform planetary in-situ measurements. VISTA can detect and quantify the presence of volatile compounds of astrobiological interest, such as water and organics, in planetary samples. These measurements can be particularly relevant when performed on primitive asteroids or comets, or on targets of potential astrobiological interest such as Mars or Jupiter's satellite Europa. VISTA is based on a micro-thermogravimetry technique, widely used in different environments to study absorption and sublimation processes. The instrument core is a piezoelectric crystal microbalance, whose frequency variations are affected by variations of the mass of the deposited sample, due to chemical processes such as sublimation, condensation or absorption/desorption. The low mass (i.e. 40 g), the low volume (less than 10 cm(3)) and the low power (less than 1 W) required makes this kind of instrument very suitable for space missions. This paper discusses the planetary applications of VISTA, and shows the calibration operations performed on the breadboard, as well as the performance tests which demonstrate the capability of the breadboard to characterize volatile compounds of planetary interests.
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Affiliation(s)
| | | | - Fabrizio Dirri
- IAPS-INAF, via Fosso del Cavaliere 100, 00133, Rome, Italy
| | | | - David Biondi
- IAPS-INAF, via Fosso del Cavaliere 100, 00133, Rome, Italy
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Loeffler MJ, Hudson RL. Descent without Modification? The Thermal Chemistry of H2O2 on Europa and Other Icy Worlds. ASTROBIOLOGY 2015; 15:453-461. [PMID: 26060983 DOI: 10.1089/ast.2014.1195] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The strong oxidant H2O2 is known to exist in solid form on Europa and is suspected to exist on several other Solar System worlds at temperatures below 200 K. However, little is known of the thermal chemistry that H2O2 might induce under these conditions. Here, we report new laboratory results on the reactivity of solid H2O2 with eight different compounds in H2O-rich ices. Using infrared spectroscopy, we monitored compositional changes in ice mixtures during warming. The compounds CH4 (methane), C3H4 (propyne), CH3OH (methanol), and CH3CN (acetonitrile) were unaltered by the presence of H2O2 in ices, showing that exposure to either solid H2O2 or frozen H2O+H2O2 at cryogenic temperatures will not oxidize these organics, much less convert them to CO2. This contrasts strongly with the much greater reactivity of organics with H2O2 at higher temperatures, and particularly in the liquid and gas phases. Of the four inorganic compounds studied, CO, H2S, NH3, and SO2, only the last two reacted in ices containing H2O2, NH3 making NH4+ and SO2 making SO(4)2- by H+ and e- transfer, respectively. An important astrobiological conclusion is that formation of surface H2O2 on Europa and that molecule's downward movement with H2O-ice do not necessarily mean that all organics encountered in icy subsurface regions will be destroyed by H2O2 oxidation.
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Affiliation(s)
- Mark J Loeffler
- Astrochemistry Laboratory, NASA Goddard Space Flight Center , Greenbelt, Maryland
| | - Reggie L Hudson
- Astrochemistry Laboratory, NASA Goddard Space Flight Center , Greenbelt, Maryland
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Orbital apocenter is not a sufficient condition for HST/STIS detection of Europa's water vapor aurora. Proc Natl Acad Sci U S A 2014; 111:E5123-32. [PMID: 25404343 DOI: 10.1073/pnas.1416671111] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report far-ultraviolet observations of Jupiter's moon Europa taken by Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope (HST) in January and February 2014 to test the hypothesis that the discovery of a water vapor aurora in December 2012 by local hydrogen (H) and oxygen (O) emissions with the STIS originated from plume activity possibly correlated with Europa's distance from Jupiter through tidal stress variations. The 2014 observations were scheduled with Europa near the apocenter similar to the orbital position of its previous detection. Tensile stresses on south polar fractures are expected to be highest in this orbital phase, potentially maximizing the probability for plume activity. No local H and O emissions were detected in the new STIS images. In the south polar region where the emission surpluses were observed in 2012, the brightnesses are sufficiently low in the 2014 images to be consistent with any H2O abundance from (0-5)×10(15) cm(-2). Large high-latitude plumes should have been detectable by the STIS, independent of the observing conditions and geometry. Because electron excitation of water vapor remains the only viable explanation for the 2012 detection, the new observations indicate that although the same orbital position of Europa for plume activity may be a necessary condition, it is not a sufficient condition. However, the December 2012 detection of coincident HI Lyman-α and OI 1304-Å emission surpluses in an ∼200-km high region well separated above Europa's limb is a firm result and not invalidated by our 2014 STIS observations.
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Heller R, Williams D, Kipping D, Limbach MA, Turner E, Greenberg R, Sasaki T, Bolmont É, Grasset O, Lewis K, Barnes R, Zuluaga JI. Formation, habitability, and detection of extrasolar moons. ASTROBIOLOGY 2014; 14:798-835. [PMID: 25147963 PMCID: PMC4172466 DOI: 10.1089/ast.2014.1147] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 06/05/2014] [Indexed: 06/03/2023]
Abstract
The diversity and quantity of moons in the Solar System suggest a manifold population of natural satellites exist around extrasolar planets. Of peculiar interest from an astrobiological perspective, the number of sizable moons in the stellar habitable zones may outnumber planets in these circumstellar regions. With technological and theoretical methods now allowing for the detection of sub-Earth-sized extrasolar planets, the first detection of an extrasolar moon appears feasible. In this review, we summarize formation channels of massive exomoons that are potentially detectable with current or near-future instruments. We discuss the orbital effects that govern exomoon evolution, we present a framework to characterize an exomoon's stellar plus planetary illumination as well as its tidal heating, and we address the techniques that have been proposed to search for exomoons. Most notably, we show that natural satellites in the range of 0.1-0.5 Earth mass (i) are potentially habitable, (ii) can form within the circumplanetary debris and gas disk or via capture from a binary, and (iii) are detectable with current technology.
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Affiliation(s)
- René Heller
- Origins Institute, Department of Physics and Astronomy, McMaster University, Hamilton, Canada
| | - Darren Williams
- The Behrend College School of Science, Penn State Erie, Erie, Pennsylvania, USA
| | - David Kipping
- Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA
| | - Mary Anne Limbach
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey, USA
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey, USA
| | - Edwin Turner
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey, USA
- The Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, Kashiwa, Japan
| | - Richard Greenberg
- Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona, USA
| | | | - Émeline Bolmont
- Université de Bordeaux, LAB, UMR 5804, Floirac, France
- CNRS, LAB, UMR 5804, Floirac, France
| | - Olivier Grasset
- Planetology and Geodynamics, University of Nantes, CNRS, Nantes, France
| | - Karen Lewis
- Earth and Planetary Sciences, Tokyo Institute of Technology, Tokyo, Japan
| | - Rory Barnes
- Astronomy Department, University of Washington, Seattle, Washington, USA
- NASA Astrobiology Institute—Virtual Planetary Laboratory Lead Team, USA
| | - Jorge I. Zuluaga
- FACom—Instituto de Física—FCEN, Universidad de Antioquia, Medellín, Colombia
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Roth L, Saur J, Retherford KD, Strobel DF, Feldman PD, McGrath MA, Nimmo F. Transient Water Vapor at Europa’s South Pole. Science 2014; 343:171-4. [DOI: 10.1126/science.1247051] [Citation(s) in RCA: 326] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Lorenz Roth
- Southwest Research Institute, San Antonio, TX, USA
- Institute of Geophysics and Meteorology, University of Cologne, Germany
| | - Joachim Saur
- Institute of Geophysics and Meteorology, University of Cologne, Germany
| | | | - Darrell F. Strobel
- Department of Earth and Planetary Science, The Johns Hopkins University, Baltimore, MD, USA
- Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD, USA
| | - Paul D. Feldman
- Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD, USA
| | | | - Francis Nimmo
- Department of Earth and Planetary Sciences, University of California Santa Cruz, CA, USA
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Pappalardo RT, Vance S, Bagenal F, Bills BG, Blaney DL, Blankenship DD, Brinckerhoff WB, Connerney JEP, Hand KP, Hoehler TM, Leisner JS, Kurth WS, McGrath MA, Mellon MT, Moore JM, Patterson GW, Prockter LM, Senske DA, Schmidt BE, Shock EL, Smith DE, Soderlund KM. Science potential from a Europa lander. ASTROBIOLOGY 2013; 13:740-773. [PMID: 23924246 DOI: 10.1089/ast.2013.1003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The prospect of a future soft landing on the surface of Europa is enticing, as it would create science opportunities that could not be achieved through flyby or orbital remote sensing, with direct relevance to Europa's potential habitability. Here, we summarize the science of a Europa lander concept, as developed by our NASA-commissioned Science Definition Team. The science concept concentrates on observations that can best be achieved by in situ examination of Europa from its surface. We discuss the suggested science objectives and investigations for a Europa lander mission, along with a model planning payload of instruments that could address these objectives. The highest priority is active sampling of Europa's non-ice material from at least two different depths (0.5-2 cm and 5-10 cm) to understand its detailed composition and chemistry and the specific nature of salts, any organic materials, and other contaminants. A secondary focus is geophysical prospecting of Europa, through seismology and magnetometry, to probe the satellite's ice shell and ocean. Finally, the surface geology can be characterized in situ at a human scale. A Europa lander could take advantage of the complex radiation environment of the satellite, landing where modeling suggests that radiation is about an order of magnitude less intense than in other regions. However, to choose a landing site that is safe and would yield the maximum science return, thorough reconnaissance of Europa would be required prior to selecting a scientifically optimized landing site.
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Affiliation(s)
- R T Pappalardo
- Planetary Sciences Section, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
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Muñoz-Iglesias V, Bonales LJ, Prieto-Ballesteros O. pH and salinity evolution of Europa's brines: Raman spectroscopy study of fractional precipitation at 1 and 300 bar. ASTROBIOLOGY 2013; 13:693-702. [PMID: 23944292 DOI: 10.1089/ast.2012.0900] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Several lines of evidence indicate the existence of salty liquid water below the icy surface of the satellite Europa. Depending on the chemical composition of the original interior brines, minerals that precipitate will be varied as will be the resulting physicochemical parameters of the evolving solutions such as pH and salinity. These parameters are determinants apropos to the study of the possible habitability of the satellite. In this work, experiments of fractional precipitation by cooling of several brines with different chemical composition (acid, alkaline, and neutral) were performed at 1 and 300 bar. The gradual decrease in temperature leads to mineral precipitation and changes in salinity and pH values. During the experiment, Raman spectroscopy was used to analyze quantitatively the variation of the salt concentration in the aqueous solutions. The obtained laboratory data indicate the manner in which cryomagma differentiation might occur on Europa. These endogenous processes of differentiation require planetary energy, which seems to have been plentiful during Europa's geological history. Ultimately, the dissipation of part of that energy is translated to a higher complexity of the cryopetrology in Europa's crust. From the results, we conclude that fractional differentiation processes of briny cryomagmas produce several types of igneous salty mineral suites on icy moons.
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Carr CE, Rowedder H, Lui CS, Zlatkovsky I, Papalias CW, Bolander J, Myers JW, Bustillo J, Rothberg JM, Zuber MT, Ruvkun G. Radiation resistance of sequencing chips for in situ life detection. ASTROBIOLOGY 2013; 13:560-569. [PMID: 23734755 DOI: 10.1089/ast.2012.0923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Life beyond Earth may be based on RNA or DNA if such life is related to life on Earth through shared ancestry due to meteoritic exchange, such as may be the case for Mars, or if delivery of similar building blocks to habitable environments has biased the evolution of life toward utilizing nucleic acids. In this case, in situ sequencing is a powerful approach to identify and characterize such life without the limitations or expense of returning samples to Earth, and can monitor forward contamination. A new semiconductor sequencing technology based on sensing hydrogen ions released during nucleotide incorporation can enable massively parallel sequencing in a small, robust, optics-free CMOS chip format. We demonstrate that these sequencing chips survive several analogues of space radiation at doses consistent with a 2-year Mars mission, including protons with solar particle event-distributed energy levels and 1 GeV oxygen and iron ions. We find no measurable impact of irradiation at 1 and 5 Gy doses on sequencing quality nor on low-level hardware characteristics. Further testing is required to study the impacts of soft errors as well as to characterize performance under neutron and gamma irradiation and at higher doses, which would be expected during operation in environments with significant trapped energetic particles such as during a mission to Europa. Our results support future efforts to use in situ sequencing to test theories of panspermia and/or whether life has a common chemical basis.
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Affiliation(s)
- Christopher E Carr
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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Carr CE, Rowedder H, Vafadari C, Lui CS, Cascio E, Zuber MT, Ruvkun G. Radiation resistance of biological reagents for in situ life detection. ASTROBIOLOGY 2013; 13:68-78. [PMID: 23330963 DOI: 10.1089/ast.2012.0869] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Life on Mars, if it exists, may share a common ancestry with life on Earth derived from meteoritic transfer of microbes between the planets. One means to test this hypothesis is to isolate, detect, and sequence nucleic acids in situ on Mars, then search for similarities to known common features of life on Earth. Such an instrument would require biological and chemical components, such as polymerase and fluorescent dye molecules. We show that reagents necessary for detection and sequencing of DNA survive several analogues of the radiation expected during a 2-year mission to Mars, including proton (H-1), heavy ion (Fe-56, O-18), and neutron bombardment. Some reagents have reduced performance or fail at higher doses. Overall, our findings suggest it is feasible to utilize space instruments with biological components, particularly for mission durations of up to several years in environments without large accumulations of charged particles, such as the surface of Mars, and have implications for the meteoritic transfer of microbes between planets.
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Affiliation(s)
- Christopher E Carr
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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Mora MF, Stockton AM, Willis PA. Microchip capillary electrophoresis instrumentation for in situ analysis in the search for extraterrestrial life. Electrophoresis 2012; 33:2624-38. [DOI: 10.1002/elps.201200102] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Angel SM, Gomer NR, Sharma SK, McKay C. Remote Raman spectroscopy for planetary exploration: a review. APPLIED SPECTROSCOPY 2012; 66:137-50. [PMID: 22449277 DOI: 10.1366/11-06535] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In this review, we discuss the current state of standoff Raman spectroscopy as it applies to remote planetary applications, including standoff instrumentation, the technique's ability to identify biologically and geologically important analytes, and the feasibility to make standoff Raman measurements under various planetary conditions. This is not intended to be an exhaustive review of standoff Raman and many excellent papers are not mentioned. Rather it is intended to give the reader a quick review of the types of standoff Raman systems that are being developed and that might be suitable for astrospectroscopy, a look at specific analytes that are of interest for planetary applications, planetary measurement opportunities and challenges that need to be solved, and a brief discussion of the feasibility of making surface and plume planetary Raman measurements from an orbiting spacecraft.
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Affiliation(s)
- S Michael Angel
- Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, South Carolina 29208, USA.
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Active formation of 'chaos terrain' over shallow subsurface water on Europa. Nature 2011; 479:502-5. [PMID: 22089135 DOI: 10.1038/nature10608] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Accepted: 10/04/2011] [Indexed: 11/08/2022]
Abstract
Europa, the innermost icy satellite of Jupiter, has a tortured young surface and sustains a liquid water ocean below an ice shell of highly debated thickness. Quasi-circular areas of ice disruption called chaos terrains are unique to Europa, and both their formation and the ice-shell thickness depend on Europa's thermal state. No model so far has been able to explain why features such as Conamara Chaos stand above surrounding terrain and contain matrix domes. Melt-through of a thin (few-kilometre) shell is thermodynamically improbable and cannot raise the ice. The buoyancy of material rising as either plumes of warm, pure ice called diapirs or convective cells in a thick (>10 kilometres) shell is insufficient to produce the observed chaos heights, and no single plume can create matrix domes. Here we report an analysis of archival data from Europa, guided by processes observed within Earth's subglacial volcanoes and ice shelves. The data suggest that chaos terrains form above liquid water lenses perched within the ice shell as shallow as 3 kilometres. Our results suggest that ice-water interactions and freeze-out give rise to the diverse morphologies and topography of chaos terrains. The sunken topography of Thera Macula indicates that Europa is actively resurfacing over a lens comparable in volume to the Great Lakes in North America.
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Hellevang H, Huang S, Thorseth IH. The potential for low-temperature abiotic hydrogen generation and a hydrogen-driven deep biosphere. ASTROBIOLOGY 2011; 11:711-724. [PMID: 21923409 PMCID: PMC3176347 DOI: 10.1089/ast.2010.0559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Accepted: 04/03/2011] [Indexed: 05/31/2023]
Abstract
The release and oxidation of ferrous iron during aqueous alteration of the mineral olivine is known to reduce aqueous solutions to such extent that molecular hydrogen, H2, forms. H2 is an efficient energy carrier and is considered basal to the deep subsurface biosphere. Knowledge of the potential for H2 generation is therefore vital to understanding the deep biosphere on Earth and on extraterrestrial bodies. Here, we provide a review of factors that may reduce the potential for H2 generation with a focus on systems in the core temperature region for thermophilic to hyperthermophilic microbial life. We show that aqueous sulfate may inhibit the formation of H2, whereas redox-sensitive compounds of carbon and nitrogen are unlikely to have significant effect at low temperatures. In addition, we suggest that the rate of H2 generation is proportional to the dissolution rate of olivine and, hence, limited by factors such as reactive surface areas and the access of water to fresh surfaces. We furthermore suggest that the availability of water and pore/fracture space are the most important factors that limit the generation of H2. Our study implies that, because of large heat flows, abundant olivine-bearing rocks, large thermodynamic gradients, and reduced atmospheres, young Earth and Mars probably offered abundant systems where microbial life could possibly have emerged.
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Affiliation(s)
- Helge Hellevang
- Department of Geosciences, University of Oslo, Oslo, Norway.
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McKay CP. The search for life in our Solar System and the implications for science and society. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2011; 369:594-606. [PMID: 21220283 DOI: 10.1098/rsta.2010.0247] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The search for another type of life in the Solar System addresses the fundamental question of life in the Universe. To determine if life forms we discover represent a second genesis, we must find biological material that would allow us to compare that life to the Earth's phylogenetic tree of life. An organism would be alien if, and only if, it did not link to our tree of life. In our Solar System, the worlds of interest for a search for life are Mars, Europa, Enceladus and, for biochemistry based on a liquid other than water, Titan. If we find evidence for a second genesis of life, we will certainly learn from the comparative study of the biochemistry, organismal biology and ecology of the alien life. The discovery of alien life, if alive or revivable, will pose fundamentally new questions in environmental ethics. We should plan our exploration strategy such that we conduct biologically reversible exploration. In the long term we would do well, ethically and scientifically, to strive to support any alien life discovered as part of an overall commitment to enhancing the richness and diversity of life in the Universe.
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Affiliation(s)
- Christopher P McKay
- Space Science Division, NASA Ames Research Center, Moffett Field, CA 94035, USA.
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Probe technology for the direct measurement and sampling of Ellsworth Subglacial Lake. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010gm001013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Abstract
AbstractGalileo spacecraft data suggest that a global ocean exists beneath the frozen ice surface Jupiter's moon Europa. Since the early 1970s, planetary scientists have used theoretical and observational arguments to deliberate the existence of an ocean within Europa and other large icy satellites. Galileo magnetometry data indicates an induced magnetic field at Europa, implying a salt water ocean. A paucity of large craters argues for a surface on average only ~40-90 Myr old. Two multi-ring structures suggest that impacts punched through an ice shell ~20 km thick. Europa's ocean and surface are inherently linked through tidal deformation of the floating ice shell, and tidal flexing and nonsynchronous rotation generate stresses that fracture and deform the surface to create ridges and bands. Dark spots, domes, and chaos terrain are probably related to tidally driven ice convection along with partial melting within the ice shell. Europa's geological activity and probable mantle contact permit the chemical ingredients necessary for life to be present within the satellite's ocean. Astonishing geology and high astrobiological potential make Europa a top priority for future spacecraft exploration, with a primary goal of assessing its habitability.
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