Astrobiological Potential of Venus Atmosphere Chemical Anomalies and Other Unexplained Cloud Properties

Astrobiology, Journal Year: 2024, Volume and Issue: 24(4), P. 343 - 370

Published: March 7, 2024

Long-standing unexplained Venus atmosphere observations and chemical anomalies point to unknown chemistry but also leave room for the possibility of life. The include several gases out thermodynamic equilibrium (e.g., tens ppm O2, possible presence PH3 NH3, SO2 H2O vertical abundance profiles), an composition large, lower cloud particles, "unknown absorber(s)." Here we first review relevant properties venusian then describe atmospheric how they motivate future astrobiology missions Venus.

Language: Английский

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Venus Evolution Through Time: Key Science Questions, Selected Mission Concepts and Future Investigations

Space Science Reviews, Journal Year: 2023, Volume and Issue: 219(7)

Published: Oct. 1, 2023

Abstract In this work we discuss various selected mission concepts addressing Venus evolution through time. More specifically, address investigations and payload instrument supporting scientific goals open questions presented in the companion articles of volume. Also included are their related (observations & modeling) discussion which measurements future data products needed to better constrain Venus’ atmosphere, climate, surface, interior habitability A new fleet missions has been selected, will continue be considered for selections. Missions under development include radar-equipped ESA-led EnVision M5 orbiter (European Space Agency 2021), NASA-JPL’s VERITAS (Smrekar et al. 2022a), NASA-GSFC’s DAVINCI entry probe/flyby (Garvin 2022a). The acquired with VERITAS, DAVINCI, from end decade fundamentally improve our understanding planet’s long term history, current activity evolutionary path. We further describe beyond framework missions, as well synergies between these concepts, ground-based space-based observatories facilities, laboratory measurements, algorithmic or modeling activities that pave way a program extends into 2040s (Wilson 2022).

Language: Английский

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The Habitability of Venus

Space Science Reviews, Journal Year: 2023, Volume and Issue: 219(2)

Published: Feb. 22, 2023

Abstract Venus today is inhospitable at the surface, its average temperature of 750 K being incompatible to existence life as we know it. However, potential for past surface habitability and upper atmosphere (cloud) present day hotly debated, ongoing discussion regarding a possible phosphine signature coming from clouds shows. We review current understanding about evolution with special attention scenarios where planet may have been capable hosting microbial life. compare possibility on case Earth by reviewing various hypotheses put forth concerning origin habitable conditions emergence plate tectonics both planets. Life emerged during Hadean when was dominated higher mantle temperatures (by $200~^{\circ}\text{C}$ 200∘C ), an uncertain tectonic regime that likely included squishy lid/plume-lid tectonics, proto continents. Despite lack well-preserved crust dating Paleoarchean, attempt environmental this critical period based zircon crystals geochemical signatures period, well studies younger, relatively rocks Paleoarchean. For these early, primitive forms, not but it became important means nutrient recycling, consequences global environment in long-term, essential continuation early Venus, question stable water closely related tectonics. discuss transitions between stagnant lid (episodic) crustal volatile cycling Venus’ interior atmosphere. In particular, insights into climate examine questions rotation speed, reflective clouds, silicate weathering, summarize implications long-term habitability. Finally, state knowledge Venusian proposed detection covered.

Language: Английский

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Stability of nucleic acid bases in concentrated sulfuric acid: Implications for the habitability of Venus’ clouds

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(25)

Published: June 12, 2023

What constitutes a habitable planet is frontier to be explored and requires pushing the boundaries of our terracentric viewpoint for what we deem environment. Despite Venus' 700 K surface temperature being too hot any plausible solvent most organic covalent chemistry, cloud-filled atmosphere layers at 48 60 km above hold main requirements life: suitable temperatures bonds; an energy source (sunlight); liquid solvent. Yet, Venus clouds are widely thought incapable supporting life because droplets composed concentrated sulfuric acid-an aggressive that assumed rapidly destroy biochemicals on Earth. Recent work, however, demonstrates rich chemistry can evolve from simple precursor molecules seeded into acid, result corroborated by domain knowledge in industry such leads complex molecules, including aromatics. We aim expand set known stable acid. Here, show nucleic acid bases adenine, cytosine, guanine, thymine, uracil, as well 2,6-diaminopurine "core" purine pyrimidine, cloud concentration range, using UV spectroscopy combinations 1D 2D

Language: Английский

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Stability of 20 Biogenic Amino Acids in Concentrated Sulfuric Acid: Implications for the Habitability of Venus' Clouds

Astrobiology, Journal Year: 2024, Volume and Issue: 24(4), P. 386 - 396

Published: March 18, 2024

Scientists have long speculated about the potential habitability of Venus, not at 700K surface, but in cloud layers located 48–60 km altitudes, where temperatures match those found on Earth's surface. However, prevailing belief has been that Venus' clouds cannot support life due to chemical composition concentrated sulfuric acid—a highly aggressive solvent. In this work, we study 20 biogenic amino acids range acid concentrations (81% and 98% w/w, rest water) temperatures. We find 19 tested are either unreactive (13 w/w 12 81% w/w) or chemically modified side chain only, after 4 weeks. Our major finding, therefore, is backbone remains intact acid. These findings significantly broaden biologically relevant molecules could be components a biochemistry based

Language: Английский

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Venus' Atmospheric Chemistry and Cloud Characteristics Are Compatible with Venusian Life

Astrobiology, Journal Year: 2023, Volume and Issue: 24(4), P. 371 - 385

Published: June 12, 2023

Venus is Earth's sister planet, with similar mass and density but an uninhabitably hot surface, atmosphere a water activity 50-100 times lower than anywhere on Earths' clouds believed to be made of concentrated sulfuric acid. These features have been taken imply that the chances finding life are vanishingly small, several authors describing Venus' as "uninhabitable", apparent signs there must therefore abiotic, or artefactual. In this article, we argue although many can rule out possibility Earth could live there, none all based what know physical principle Earth. Specifically, abundant energy, energy requirements for retaining capturing hydrogen atoms build biomass not excessive, defenses against acid conceivable terrestrial precedent, speculative uses solvent instead remains. Metals likely available in limited supply, radiation environment benign. The support readily detectable by future astrobiology-focused space missions from its impact atmosphere. Although consider prospects speculative, they absent. scientific reward such un-Earthlike justifies considering how observations should designed capable detecting if it there.

Language: Английский

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An Approach for Practical Grid-Resolved Roughness Aerothermodynamic Simulations for Woven Heatshield Surfaces

AIAA SCITECH 2022 Forum, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 3, 2025

Language: Английский

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Single-fluid simulation of partially-ionized, non-ideal plasma facilitated by a tabulated equation of state

AIP Advances, Journal Year: 2025, Volume and Issue: 15(2)

Published: Feb. 1, 2025

We present a single-fluid approach for the simulation of partially-ionized plasmas (PIPs), which is designed to capture non-ideal effects introduced by neutrals while maintaining computational efficiency close that magnetohydrodynamic (MHD). This achieved using model treats entire partially ionized plasma as single mixture, renders internal ionization/recombination source terms unnecessary both charged and neutral species are part mixture’s conservative system. Instead, ionization differing physics encapsulated material properties mixture. Furthermore, dynamics between captured relative-velocity quantity, impacts bulk behavior mixture in manner similar treatment ion-electron current MHD. Unlike fully-ionized plasmas, composition PIP changes rapidly with its thermodynamic state. through look-up table referred tabulated equation state (TabEoS), constructed prior runtime empirical physicochemical databases efficiently provides fraction other specific each cell. Crucially, use TabEoS also allows our self-consistently non-linear feedback cycle PIP’s macroscopic microscopic particles, neglected many fluid simulations today.

Language: Английский

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Stability of 20 Biogenic Amino Acids in Concentrated Sulfuric Acid: Implications for the Habitability of Venus' Clouds

arXiv (Cornell University), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Scientists have long speculated about the potential habitability of Venus, not at 700K surface, but in cloud layers located 48-60 km altitudes, where temperatures match those found on Earth's surface. However, prevailing belief has been that Venus' clouds cannot support life due to chemical composition concentrated sulfuric acid-a highly aggressive solvent. In this work, we study 20 biogenic amino acids range acid concentrations (81% and 98% w/w, rest water) temperatures. We find 19 tested are either unreactive (13 w/w 12 81% w/w) or chemically modified side chain only, after 4 weeks. Our major finding, therefore, is backbone remains intact acid. These findings significantly broaden biologically relevant molecules could be components a biochemistry based

Language: Английский

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The COSPAR planetary protection requirements for space missions to Venus

Life Sciences in Space Research, Journal Year: 2023, Volume and Issue: 37, P. 18 - 24

Published: Feb. 4, 2023

The Committee on Space Research's (COSPAR) Planetary Protection Policy states that all types of missions to Venus are classified as Category II, the planet has significant research interest relative processes chemical evolution and origin life, but there is only a remote chance terrestrial contamination can proliferate compromise future investigations. "Remote chance" essentially implies absence environments where organisms could survive replicate. Hence, II require simplified planetary protection documentation, including plan outlines intended or potential impact targets, brief Pre- Post-launch analyses detailing strategies, Post-encounter End-of-Mission Report. These requirements were applied in previous foreseen for numerous new international planned exploration Venus, which include NASA's VERITAS DAVINCI missions, ESA's EnVision mission. There also several proposed India's Shukrayaan-1, Russia's Venera-D. multiple plans spacecraft coincide with recent within scientific community regarding cloud layers have been suggested by some be habitable environments. proposed, privately funded, MIT/Rocket Lab Life Finder mission specifically designed assess habitability Venusian clouds search signs life. It includes up three atmospheric probes, first one targeting launch 2023. COSPAR Panel evaluated data underpins implications this current policy. done thorough review knowledge planet's conditions prevailing clouds. Based existing literature, we conclude environmental orders magnitude drier more acidic than tolerated survival limits any known extremophile organism. Because orbital, landed entry probe do not extra measures. This recommendation may revised if observations reanalysis past show increment, magnitude, water content pH layer.

Language: Английский

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