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Geoscience for Understanding Habitability in the Solar System And Geoscience for Understanding Habitability in the Solar System and Beyond Véronique Dehant, Vinciane Debaille, Vera Dobos, Fabrice Gaillard, Cédric Gillmann, Steven Goderis, John Lee Grenfell, Dennis Höning, Emmanuelle Javaux, Ozgur Karatekin, et al. To cite this version: Véronique Dehant, Vinciane Debaille, Vera Dobos, Fabrice Gaillard, Cédric Gillmann, et al.. Geo- science for Understanding Habitability in the Solar System and Beyond. Space Science Reviews, Springer Verlag, 2019, 215 (6), 10.1007/s11214-019-0608-8. hal-02396665 HAL Id: hal-02396665 https://hal.archives-ouvertes.fr/hal-02396665 Submitted on 3 Jan 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Geoscience for understanding habitability in the solar system and beyond Veronique Dehant1, 2, Vinciane Debaille3, Vera Dobos4, 5, 6, Fabrice Gaillard7, Cedric Gillmann1, 3, Steven Goderis8, John Lee Grenfell9, Dennis Höning9, 10, Emmanuelle J. Javaux11, Özgür Karatekin1, Alessandro Morbidelli12, Lena Noack1, 13, Heike Rauer9, 13, 14, Manuel Scherf13, Tilman Spohn9, Paul Tackley16, Tim Van Hoolst1, Kai Wünnemann13, 17 1 Royal Observatory of Belgium 2 Université Catholique de Louvain, Belgium 3 Université Libre de Bruxelles, Belgium 4 Konkoly Thege Miklós Astronomical Institute, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Budapest, Hungary 5 Geodetic and Geophysical Institute, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Sopron, Hungary 6 MTA-ELTE Exoplanet Research Group, 9700, Szent Imre h. u. 112, Szombathely, Hungary 7 University of Orléans, France 8 Vrije Universiteit Brussel, Belgium 9 German Aerospace Centre (DLR), Germany 10 Vrije Universiteit Amsterdam 11 University of Liège, Belgium 12 University of Nice, France 13 Free University of Berlin, Germany 14 Berlin Institute of Technology, Germany 15 Austrian Academy of Sciences, Austria 16 ETH Zürich, Switzerland 17 Museum of Natural History, Germany Contents Geoscience for understanding habitability in the solar system and beyond ....................................... 1 Contents .................................................................................................................................................. 1 Abstract .............................................................................................................................................. 2 Introduction ........................................................................................................................................ 3 1. Formation of habitable planets ................................................................................................. 3 2. Role of cometary, meteorite and asteroid impacts on planetary evolution ........................... 5 2.1. Impactors ................................................................................................................................ 5 2.2. Surface traces of impactors .................................................................................................... 6 3. Planetary interiors, mantle convection and their evolutions ................................................... 7 3.1. Internal structure .................................................................................................................... 7 3.2. Mantle convection regime ...................................................................................................... 9 3.3. Partial melting and the volatile pipeline ............................................................................... 10 3.4. Degassing, volatile cycles, and continental cycling ............................................................... 11 1 3.5. Consequences of impacts on the interior of planets ............................................................ 14 4. Processes affecting atmospheric development ...................................................................... 17 4.1. Atmospheric escape .............................................................................................................. 18 4.2. Impacts .................................................................................................................................. 20 4.3. Outgassing and Surface Emissions ........................................................................................ 22 4.4. Surface removal .................................................................................................................... 22 5. Interaction of life with the atmosphere, geosphere and interior of planets ......................... 22 5.1. Evolution of Earth’s atmosphere .......................................................................................... 22 5.2. Other terrestrial planet atmospheres ................................................................................... 25 5.3. Influence of life on the interior evolution of planets ............................................................ 25 5.4. Combined effects on atmosphere and interior evolution .................................................... 26 6. Identification of preserved life traces in the context of the interaction of life with planetary evolution ........................................................................................................................................... 27 6.1. Life’s Origin and Environmental Tolerances ......................................................................... 27 6.2. Early Earth ............................................................................................................................. 28 6.3. Mars ...................................................................................................................................... 29 6.4. Earth-like Exoplanets ............................................................................................................ 30 7. Conclusion on habitability and planet formation in a broader context ................................. 31 Acknowledgements .......................................................................................................................... 32 References ........................................................................................................................................ 33 Abstract This paper reviews habitability conditions for a terrestrial planet from the point of view of geosciences. It addresses how interactions between the interior of a planet or a moon and its atmosphere and surface (including hydrosphere and biosphere) can affect habitability of the celestial body. It does not consider in detail the role of the central star but focusses more on surface conditions capable of sustaining life. We deal with fundamental issues of planetary habitability, i.e. the environmental conditions capable of sustaining life, and the above-mentioned interactions can affect the habitability of the celestial body. We address some hotly debated questions including: - How do core and mantle affect the evolution and habitability of planets? - What are the consequences of mantle overturn on the evolution of the interior and atmosphere? - What is the role of the global carbon and water cycles? - What influence do comet and asteroid impacts exert on the evolution of the planet? - How does life interact with the evolution of the Earth’s geosphere and atmosphere? 2 - How can knowledge of the solar system geophysics and habitability be applied to exoplanets? In addition, we address the identification of preserved life tracers in the context of the interaction of life with planetary evolution. Introduction The bulk evolution of a planet (including the Earth) is driven by the internal energy sources and losses (radiogenic sources, energy from accretion and differentiation, tidal energy), and depends upon the composition, structure, and thermal state of its core, mantle, lithosphere, crust. These properties depend on the size and mass of the planet as well as on potential interactions with a possible ocean and atmosphere and – in the case of the Earth or other currently unknown planets possibly having life – with a biosphere. In addition, impacts (in particular, giant collision events) may have had a sustainable effect on the evolution of lithospheres, atmospheres, and biospheres. The paper has a different focus than most other habitability discussions in Earth-System sciences, planetary sciences and astronomy by encompassing the entire planet from the upper atmosphere to the deep interior and by including the exogenic influence within the framework of the study of its habitability. In this aspect, it is broader in scope than e.g., Lammer et al. (2009), Javaux and Dehant (2010), Spohn (2014), Fritz et al. (2014), Southam et al. (2015), Cockell et al. (2016), and Tosi et al. (2017). The paper addresses questions within six main sections: (1) Formation of habitable planets, (2) role of cometary, meteorite and asteroid impacts on planetary evolution, (3) planetary interiors, mantle convection and their
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