1
|
Shorttle O, Saeidfirozeh H, Rimmer PB, Laitl V, Kubelík P, Petera L, Ferus M. Impact sculpting of the early martian atmosphere. SCIENCE ADVANCES 2024; 10:eadm9921. [PMID: 39259790 DOI: 10.1126/sciadv.adm9921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 08/06/2024] [Indexed: 09/13/2024]
Abstract
Intense bombardment of solar system planets in the immediate aftermath of protoplanetary disk dissipation has played a key role in their atmospheric evolution. During this epoch, energetic collisions will have removed substantial masses of gas from rocky planet atmospheres. Noble gases are powerful tracers of this early atmospheric history, xenon in particular, which on Mars and Earth shows significant depletions and isotopic fractionations relative to the lighter noble gasses. To evaluate the effect of impacts on the loss and fractionation of xenon, we measure its ionization and recombination efficiency by laser shock and apply these constraints to model impact-driven atmospheric escape on Mars. We demonstrate that impact bombardment within the first 200 to 300 million years of solar system history generates the observed Xe depletion and isotope fractionation of the modern martian atmosphere. This process may also explain the Xe depletion recorded in Earth's deep mantle and provides a latest date for the timing of giant planet instability.
Collapse
Affiliation(s)
- Oliver Shorttle
- Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
| | - Homa Saeidfirozeh
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, CZ 18223 Prague 8, Czech Republic
| | - Paul Brandon Rimmer
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
- Cavendish Laboratory, University of Cambridge, JJ Thompson Avenue, Cambridge CB3 0HE, UK
| | - Vojtĕch Laitl
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, CZ 18223 Prague 8, Czech Republic
- Faculty of Science, University of Antwerp, Groenenborgerlaan 171, BE-2020 Antwerpen, Belgium
| | - Petr Kubelík
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, CZ 18223 Prague 8, Czech Republic
| | - Lukáš Petera
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, CZ 18223 Prague 8, Czech Republic
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 8, Prague, Czech Republic
| | - Martin Ferus
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, CZ 18223 Prague 8, Czech Republic
| |
Collapse
|
2
|
Rhoden AR, Ferguson SN, Bottke W, Castillo-Rogez JC, Martin E, Bland M, Kirchoff M, Zannoni M, Rambaux N, Salmon J. Geologic Constraints on the Formation and Evolution of Saturn's Mid-Sized Moons. SPACE SCIENCE REVIEWS 2024; 220:55. [PMID: 39036784 PMCID: PMC11255024 DOI: 10.1007/s11214-024-01084-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 06/13/2024] [Indexed: 07/23/2024]
Abstract
Saturn's mid-sized icy moons have complex relationships with Saturn's interior, the rings, and with each other, which can be expressed in their shapes, interiors, and geology. Observations of their physical states can, thus, provide important constraints on the ages and formation mechanism(s) of the moons, which in turn informs our understanding of the formation and evolution of Saturn and its rings. Here, we describe the cratering records of the mid-sized moons and the value and limitations of their use for constraining the histories of the moons. We also discuss observational constraints on the interior structures of the moons and geologically-derived inferences on their thermal budgets through time. Overall, the geologic records of the moons (with the exception of Mimas) include evidence of epochs of high heat flows, short- and long-lived subsurface oceans, extensional tectonics, and considerable cratering. Curiously, Mimas presents no clear evidence of an ocean within its surface geology, but its rotation and orbit indicate a present-day ocean. While the moons need not be primordial to produce the observed levels of interior evolution and geologic activity, there is likely a minimum age associated with their development that has yet to be determined. Uncertainties in the populations impacting the moons makes it challenging to further constrain their formation timeframes using craters, whereas the characteristics of their cores and other geologic inferences of their thermal evolutions may help narrow down their potential histories. Disruptive collisions may have also played an important role in the formation and evolution of Saturn's mid-sized moons, and even the rings of Saturn, although more sophisticated modeling is needed to determine the collision conditions that produce rings and moons that fit the observational constraints. Overall, the existence and physical characteristics of Saturn's mid-sized moons provide critical benchmarks for the development of formation theories.
Collapse
Affiliation(s)
| | | | - William Bottke
- Southwest Research Institute, 1050 Walnut St, Boulder, CO 80302 USA
| | | | - Emily Martin
- Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washington, DC USA
| | - Michael Bland
- U.S. Geological Survey, Astrogeology Science Center, Flagstaff, AZ USA
| | | | - Marco Zannoni
- Dipartimento di Ingegneria Industriale, Alma Mater Studiorum – Università di Bologna, Forlì, Italy
| | - Nicolas Rambaux
- IMCCE, CNRS, Observatoire de Paris, PSL Université, Sorbonne Université, Université de Lille 1, UMR 8028 du CNRS, 77 Denfert-Rochereau, 75014 Paris, France
| | - Julien Salmon
- Southwest Research Institute, 1050 Walnut St, Boulder, CO 80302 USA
| |
Collapse
|
3
|
Lin Y, Yang W, Zhang H, Hui H, Hu S, Xiao L, Liu J, Xiao Z, Yue Z, Zhang J, Liu Y, Yang J, Lin H, Zhang A, Guo D, Gou S, Xu L, He Y, Zhang X, Qin L, Ling Z, Li X, Du A, He H, Zhang P, Cao J, Li X. Return to the Moon: New perspectives on lunar exploration. Sci Bull (Beijing) 2024; 69:2136-2148. [PMID: 38777682 DOI: 10.1016/j.scib.2024.04.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/24/2024] [Accepted: 04/07/2024] [Indexed: 05/25/2024]
Abstract
Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.
Collapse
Affiliation(s)
- Yangting Lin
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Wei Yang
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Hui Zhang
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Hejiu Hui
- State Key Laboratory for Mineral Deposits Research and School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Sen Hu
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Long Xiao
- State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Jianzhong Liu
- Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
| | - Zhiyong Xiao
- Planetary Environmental and Astrobiological Research Laboratory, School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Zongyu Yue
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Jinhai Zhang
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Yang Liu
- National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
| | - Jing Yang
- Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
| | - Honglei Lin
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Aicheng Zhang
- State Key Laboratory for Mineral Deposits Research and School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
| | - Dijun Guo
- National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
| | - Sheng Gou
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Lin Xu
- National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
| | - Yuyang He
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Xianguo Zhang
- National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
| | - Liping Qin
- Deep Space Exploration Laboratory / CAS Key Laboratory of Crust-Mantle Materials and Environments, University of Science and Technology of China, Hefei 230026, China
| | - Zongcheng Ling
- Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai 264209, China
| | - Xiongyao Li
- Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
| | - Aimin Du
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Huaiyu He
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Peng Zhang
- Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences, Beijing 100094, China
| | - Jinbin Cao
- School of Space and Environment, Beihang University, Beijing 100191, China
| | - Xianhua Li
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
| |
Collapse
|
4
|
Avdellidou C, Delbo' M, Nesvorný D, Walsh KJ, Morbidelli A. Dating the Solar System's giant planet orbital instability using enstatite meteorites. Science 2024; 384:348-352. [PMID: 38624242 DOI: 10.1126/science.adg8092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 02/16/2024] [Indexed: 04/17/2024]
Abstract
The giant planets of the Solar System formed on initially compact orbits, which transitioned to the current wider configuration by means of an orbital instability. The timing of that instability is poorly constrained. In this work, we use dynamical simulations to demonstrate that the instability implanted planetesimal fragments from the terrestrial planet region into the asteroid main belt. We use meteorite data to show that the implantation occurred >60 million years (Myr) after the Solar System began to form. Combining this constraint with a previous upper limit derived from Jupiter's trojan asteroids, we conclude that the orbital instability occurred 60 to 100 Myr after the beginning of Solar System formation. The giant impact that formed the Moon occurred within this range, so it might be related to the giant planet instability.
Collapse
Affiliation(s)
- Chrysa Avdellidou
- Laboratoire Lagrange, Centre National de la Recherche Scientifique, Observatoire de la Côte d'Azur, Université Côte d'Azur, 06304 Nice, France
- School of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | - Marco Delbo'
- Laboratoire Lagrange, Centre National de la Recherche Scientifique, Observatoire de la Côte d'Azur, Université Côte d'Azur, 06304 Nice, France
- School of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
| | | | - Kevin J Walsh
- Southwest Research Institute, Boulder, CO 80302, USA
| | - Alessandro Morbidelli
- Laboratoire Lagrange, Centre National de la Recherche Scientifique, Observatoire de la Côte d'Azur, Université Côte d'Azur, 06304 Nice, France
- Collège de France, Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Sorbonne Université, 75014 Paris, France
| |
Collapse
|
5
|
Schaible MJ, Todd ZR, Cangi EM, Harman CE, Hughson KHG, Stelmach K. Chapter 3: The Origins and Evolution of Planetary Systems. ASTROBIOLOGY 2024; 24:S57-S75. [PMID: 38498821 DOI: 10.1089/ast.2021.0127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The materials that form the diverse chemicals and structures on Earth-from mountains to oceans and biological organisms-all originated in a universe dominated by hydrogen and helium. Over billions of years, the composition and structure of the galaxies and stars evolved, and the elements of life, CHONPS, were formed through nucleosynthesis in stellar cores. Climactic events such as supernovae and stellar collisions produced heavier elements and spread them throughout the cosmos, often to be incorporated into new, more metal-rich stars. Stars typically form in molecular clouds containing small amounts of dust through the collapse of a high-density core. The surrounding nebular material is then pulled into a protoplanetary disk, from which planets, moons, asteroids, and comets eventually accrete. During the accretion of planetary systems, turbulent mixing can expose matter to a variety of different thermal and radiative environments. Chemical and physical changes in planetary system materials occur before and throughout the process of accretion, though many factors such as distance from the star, impact history, and level of heating experienced combine to ultimately determine the final geophysical characteristics. In Earth's planetary system, called the Solar System, after the orbits of the planets had settled into their current configuration, large impacts became rare, and the composition of and relative positions of objects became largely fixed. Further evolution of the respective chemical and physical environments of the planets-geosphere, hydrosphere, and atmosphere-then became dependent on their local geochemistry, their atmospheric interactions with solar radiation, and smaller asteroid impacts. On Earth, the presence of land, air, and water, along with an abundance of important geophysical and geochemical phenomena, led to a habitable planet where conditions were right for life to thrive.
Collapse
Affiliation(s)
- Micah J Schaible
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Zoe R Todd
- Department of Earth and Space Sciences, University of Washington, Seattle, Washington, USA
| | - Eryn M Cangi
- Department of Astrophysical and Planetary Sciences, University of Colorado Boulder, Boulder, Colorado, USA
| | | | - Kynan H G Hughson
- School of Earth and Atmospheric Science, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Kamil Stelmach
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| |
Collapse
|
6
|
Huang XL, Harmer JR, Schenk G, Southam G. Inorganic Fe-O and Fe-S oxidoreductases: paradigms for prebiotic chemistry and the evolution of enzymatic activity in biology. Front Chem 2024; 12:1349020. [PMID: 38389729 PMCID: PMC10881703 DOI: 10.3389/fchem.2024.1349020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 01/23/2024] [Indexed: 02/24/2024] Open
Abstract
Oxidoreductases play crucial roles in electron transfer during biological redox reactions. These reactions are not exclusive to protein-based biocatalysts; nano-size (<100 nm), fine-grained inorganic colloids, such as iron oxides and sulfides, also participate. These nanocolloids exhibit intrinsic redox activity and possess direct electron transfer capacities comparable to their biological counterparts. The unique metal ion architecture of these nanocolloids, including electron configurations, coordination environment, electron conductivity, and the ability to promote spontaneous electron hopping, contributes to their transfer capabilities. Nano-size inorganic colloids are believed to be among the earliest 'oxidoreductases' to have 'evolved' on early Earth, playing critical roles in biological systems. Representing a distinct type of biocatalysts alongside metalloproteins, these nanoparticles offer an early alternative to protein-based oxidoreductase activity. While the roles of inorganic nano-sized catalysts in current Earth ecosystems are intuitively significant, they remain poorly understood and underestimated. Their contribution to chemical reactions and biogeochemical cycles likely helped shape and maintain the balance of our planet's ecosystems. However, their potential applications in biomedical, agricultural, and environmental protection sectors have not been fully explored or exploited. This review examines the structure, properties, and mechanisms of such catalysts from a material's evolutionary standpoint, aiming to raise awareness of their potential to provide innovative solutions to some of Earth's sustainability challenges.
Collapse
Affiliation(s)
- Xiao-Lan Huang
- NYS Center for Clean Water Technology, School of Marine and Atmospheric Sciences, Stony Brook, NY, United States
| | - Jeffrey R Harmer
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia
| | - Gerhard Schenk
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, Australia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
- Sustainable Minerals Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Gordon Southam
- Sustainable Minerals Institute, The University of Queensland, Brisbane, QLD, Australia
- School of the Environment, The University of Queensland, Brisbane, QLD, Australia
| |
Collapse
|
7
|
Georgiev DD. Evolution of Consciousness. Life (Basel) 2023; 14:48. [PMID: 38255663 PMCID: PMC10817314 DOI: 10.3390/life14010048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/01/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
The natural evolution of consciousness in different animal species mandates that conscious experiences are causally potent in order to confer any advantage in the struggle for survival. Any endeavor to construct a physical theory of consciousness based on emergence within the framework of classical physics, however, leads to causally impotent conscious experiences in direct contradiction to evolutionary theory since epiphenomenal consciousness cannot evolve through natural selection. Here, we review recent theoretical advances in describing sentience and free will as fundamental aspects of reality granted by quantum physical laws. Modern quantum information theory considers quantum states as a physical resource that endows quantum systems with the capacity to perform physical tasks that are classically impossible. Reductive identification of conscious experiences with the quantum information comprised in quantum brain states allows for causally potent consciousness that is capable of performing genuine choices for future courses of physical action. The consequent evolution of brain cortical networks contributes to increased computational power, memory capacity, and cognitive intelligence of the living organisms.
Collapse
Affiliation(s)
- Danko D Georgiev
- Institute for Advanced Study, 30 Vasilaki Papadopulu Str., 9010 Varna, Bulgaria
| |
Collapse
|
8
|
Melis C. Violent collision rocks a young planetary system. Nature 2023; 622:249-250. [PMID: 37821587 DOI: 10.1038/d41586-023-03069-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
|
9
|
Potiszil C, Yamanaka M, Sakaguchi C, Ota T, Kitagawa H, Kunihiro T, Tanaka R, Kobayashi K, Nakamura E. Organic Matter in the Asteroid Ryugu: What We Know So Far. Life (Basel) 2023; 13:1448. [PMID: 37511823 PMCID: PMC10381145 DOI: 10.3390/life13071448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
The Hayabusa2 mission was tasked with returning samples from the C-complex asteroid Ryugu (1999 JU3), in order to shed light on the formation, evolution and composition of such asteroids. One of the main science objectives was to understand whether such bodies could have supplied the organic matter required for the origin of life on Earth. Here, a review of the studies concerning the organic matter within the Ryugu samples is presented. This review will inform the reader about the Hayabusa2 mission, the nature of the organic matter analyzed and the various interpretations concerning the analytical findings including those concerning the origin and evolution of organic matter from Ryugu. Finally, the review puts the findings and individual interpretations in the context of the current theories surrounding the formation and evolution of Ryugu. Overall, the summary provided here will help to inform those operating in a wide range of interdisciplinary fields, including planetary science, astrobiology, the origin of life and astronomy, about the most recent developments concerning the organic matter in the Ryugu return samples and their relevance to understanding our solar system and beyond. The review also outlines the issues that still remain to be solved and highlights potential areas for future work.
Collapse
Affiliation(s)
- Christian Potiszil
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Masahiro Yamanaka
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Chie Sakaguchi
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Tsutomu Ota
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Hiroshi Kitagawa
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Tak Kunihiro
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Ryoji Tanaka
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Katsura Kobayashi
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| | - Eizo Nakamura
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Yamada 827, Misasa, Tottori 682-0193, Japan
| |
Collapse
|
10
|
Briaud A, Ganino C, Fienga A, Mémin A, Rambaux N. The lunar solid inner core and the mantle overturn. Nature 2023; 617:743-746. [PMID: 37138080 DOI: 10.1038/s41586-023-05935-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 03/08/2023] [Indexed: 05/05/2023]
Abstract
Seismological models from Apollo missions provided the first records of the Moon inner structure with a decrease in seismic wave velocities at the core-mantle boundary1-3. The resolution of these records prevents a strict detection of a putative lunar solid inner core and the impact of the lunar mantle overturn in the lowest part of the Moon is still discussed4-7. Here we combine geophysical and geodesic constraints from Monte Carlo exploration and thermodynamical simulations for different Moon internal structures to show that only models with a low viscosity zone enriched in ilmenite and an inner core present densities deduced from thermodynamic constraints compatible with densities deduced from tidal deformations. We thus obtain strong indications in favour of the lunar mantle overturn scenario and, in this context, demonstrate the existence of the lunar inner core with a radius of 258 ± 40 km and density 7,822 ± 1,615 kg m-3. Our results question the evolution of the Moon magnetic field thanks to its demonstration of the existence of the inner core and support a global mantle overturn scenario that brings substantial insights on the timeline of the lunar bombardment in the first billion years of the Solar System8.
Collapse
Affiliation(s)
- Arthur Briaud
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Géoazur, Valbonne, France.
| | - Clément Ganino
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Géoazur, Valbonne, France
| | - Agnès Fienga
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Géoazur, Valbonne, France.
- IMCCE, Observatoire de Paris, Sorbonne Université, PSL University, CNRS, Paris, France.
| | - Anthony Mémin
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Géoazur, Valbonne, France
| | - Nicolas Rambaux
- IMCCE, Observatoire de Paris, Sorbonne Université, PSL University, CNRS, Paris, France
| |
Collapse
|
11
|
Bănăduc D, Simić V, Cianfaglione K, Barinova S, Afanasyev S, Öktener A, McCall G, Simić S, Curtean-Bănăduc A. Freshwater as a Sustainable Resource and Generator of Secondary Resources in the 21st Century: Stressors, Threats, Risks, Management and Protection Strategies, and Conservation Approaches. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:16570. [PMID: 36554449 PMCID: PMC9779543 DOI: 10.3390/ijerph192416570] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/01/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
This paper is a synthetic overview of some of the threats, risks, and integrated water management elements in freshwater ecosystems. The paper provides some discussion of human needs and water conservation issues related to freshwater systems: (1) introduction and background; (2) water basics and natural cycles; (3) freshwater roles in human cultures and civilizations; (4) water as a biosphere cornerstone; (5) climate as a hydrospheric 'game changer' from the perspective of freshwater; (6) human-induced stressors' effects on freshwater ecosystem changes (pollution, habitat fragmentation, etc.); (7) freshwater ecosystems' biological resources in the context of unsustainable exploitation/overexploitation; (8) invasive species, parasites, and diseases in freshwater systems; (9) freshwater ecosystems' vegetation; (10) the relationship between human warfare and water. All of these issues and more create an extremely complex matrix of stressors that plays a driving role in changing freshwater ecosystems both qualitatively and quantitatively, as well as their capacity to offer sustainable products and services to human societies. Only internationally integrated policies, strategies, assessment, monitoring, management, protection, and conservation initiatives can diminish and hopefully stop the long-term deterioration of Earth's freshwater resources and their associated secondary resources.
Collapse
Affiliation(s)
- Doru Bănăduc
- Applied Ecology Research Center, Faculty of Sciences, Lucian Blaga University of Sibiu, I. Raţiu Street 5–7, 9, 550012 Sibiu, Romania
| | - Vladica Simić
- Department of Biology and Ecology, Faculty of Science, University of Kragujevac, R. Domanovića 12, 34000 Kragujevac, Serbia
| | | | - Sophia Barinova
- Institute of Evolution, University of Haifa, Mount Carmel, 199 Abba Khoushi Avenue, Haifa 3498838, Israel
| | - Sergey Afanasyev
- Institute of Hydrobiology National Academy of Sciences of Ukraine, Prospect Geroiv Stalingradu 12, 04210 Kyiv, Ukraine
| | - Ahmet Öktener
- Ministry of Food, Agriculture and Livestock, Food Control Laboratory Directorate, Denizli 20010, Turkey
| | - Grant McCall
- Center for Human-Environmental Research (CHER), New Orleans, LA 70118, USA
| | - Snežana Simić
- Department of Biology and Ecology, Faculty of Science, University of Kragujevac, R. Domanovića 12, 34000 Kragujevac, Serbia
| | - Angela Curtean-Bănăduc
- Applied Ecology Research Center, Faculty of Sciences, Lucian Blaga University of Sibiu, I. Raţiu Street 5–7, 9, 550012 Sibiu, Romania
| |
Collapse
|
12
|
The Identification of Impact Craters from GRAIL-Acquired Gravity Data by U-Net Architecture. REMOTE SENSING 2022. [DOI: 10.3390/rs14122783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The identification of impact craters on the Moon and other planetary bodies is of great significance to studying and constraining the dynamical process and evolution of the Solar System. Traditionally, this has been performed through the visual examination of images. Due to the effect of overburden, some structural features cannot be effectively identified from optical images, resulting in limitations in the scope, efficiency and accuracy of identification. In this paper, we investigate the viability of convolutional neural networks (CNNs) to perform the detection of impact craters from GRAIL-acquired gravity data. The ideal values of each hyperparameter in U-net architecture are determined after dozens of iterations of model training, testing and evaluation. The final model was evaluated by the Loss function with the low value of 0.04, indicating that the predicted output of the model reached a relatively high fitting degree with the prior labelled output. The comparative results with different methods show that the proposed method has a clear detection of the target features, with an accuracy of more than 80%. In addition, the detection results of the whole image account for 83% of the number of manually delineated gravity anomalies. The proposed method can still achieve the same quality for the identification of the gravity anomalies caused by impact craters under the condition that the resolution of GRAIL gravity data are not superior. Our results demonstrate that the U-net architecture can be a very effective tool for the rapid and automatic identification of impact craters from gravity map on the Moon, as well as other Solar System bodies.
Collapse
|
13
|
Early Solar System instability triggered by dispersal of the gaseous disk. Nature 2022; 604:643-646. [PMID: 35478235 DOI: 10.1038/s41586-022-04535-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/08/2022] [Indexed: 11/08/2022]
Abstract
The Solar System's orbital structure is thought to have been sculpted by an episode of dynamical instability among the giant planets1-4. However, the instability trigger and timing have not been clearly established5-9. Hydrodynamical modelling has shown that while the Sun's gaseous protoplanetary disk was present the giant planets migrated into a compact orbital configuration in a chain of resonances2,10. Here we use dynamical simulations to show that the giant planets' instability was probably triggered by the dispersal of the gaseous disk. As the disk evaporated from the inside out, its inner edge swept successively across and dynamically perturbed each planet's orbit in turn. The associated orbital shift caused a dynamical compression of the exterior part of the system, ultimately triggering instability. The final orbits of our simulated systems match those of the Solar System for a viable range of astrophysical parameters. The giant planet instability therefore took place as the gaseous disk dissipated, constrained by astronomical observations to be a few to ten million years after the birth of the Solar System11. Terrestrial planet formation would not complete until after such an early giant planet instability12,13; the growing terrestrial planets may even have been sculpted by its perturbations, explaining the small mass of Mars relative to Earth14.
Collapse
|
14
|
Paschek K, Kohler K, Pearce BKD, Lange K, Henning TK, Trapp O, Pudritz RE, Semenov DA. Possible Ribose Synthesis in Carbonaceous Planetesimals. Life (Basel) 2022; 12:404. [PMID: 35330155 PMCID: PMC8955445 DOI: 10.3390/life12030404] [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: 02/14/2022] [Revised: 03/02/2022] [Accepted: 03/05/2022] [Indexed: 12/03/2022] Open
Abstract
The origin of life might be sparked by the polymerization of the first RNA molecules in Darwinian ponds during wet-dry cycles. The key life-building block ribose was found in carbonaceous chondrites. Its exogenous delivery onto the Hadean Earth could be a crucial step toward the emergence of the RNA world. Here, we investigate the formation of ribose through a simplified version of the formose reaction inside carbonaceous chondrite parent bodies. Following up on our previous studies regarding nucleobases with the same coupled physico-chemical model, we calculate the abundance of ribose within planetesimals of different sizes and heating histories. We perform laboratory experiments using catalysts present in carbonaceous chondrites to infer the yield of ribose among all pentoses (5Cs) forming during the formose reaction. These laboratory yields are used to tune our theoretical model that can only predict the total abundance of 5Cs. We found that the calculated abundances of ribose were similar to the ones measured in carbonaceous chondrites. We discuss the possibilities of chemical decomposition and preservation of ribose and derived constraints on time and location in planetesimals. In conclusion, the aqueous formose reaction might produce most of the ribose in carbonaceous chondrites. Together with our previous studies on nucleobases, we found that life-building blocks of the RNA world could be synthesized inside parent bodies and later delivered onto the early Earth.
Collapse
Affiliation(s)
- Klaus Paschek
- Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; (K.K.); (T.K.H.); (O.T.); (D.A.S.)
| | - Kai Kohler
- Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; (K.K.); (T.K.H.); (O.T.); (D.A.S.)
- Department of Chemistry, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, House F, 81377 Munich, Germany
| | - Ben K. D. Pearce
- Origins Institute, McMaster University, ABB, 1280 Main Street West, Hamilton, ON L8S 4M1, Canada; (B.K.D.P.); (R.E.P.)
- Department of Physics and Astronomy, McMaster University, ABB, 1280 Main Street West, Hamilton, ON L8S 4M1, Canada
| | - Kevin Lange
- Institute for Theoretical Astrophysics, Center for Astronomy, Heidelberg University, Albert-Ueberle-Str. 2, 69120 Heidelberg, Germany;
| | - Thomas K. Henning
- Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; (K.K.); (T.K.H.); (O.T.); (D.A.S.)
| | - Oliver Trapp
- Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; (K.K.); (T.K.H.); (O.T.); (D.A.S.)
- Department of Chemistry, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, House F, 81377 Munich, Germany
| | - Ralph E. Pudritz
- Origins Institute, McMaster University, ABB, 1280 Main Street West, Hamilton, ON L8S 4M1, Canada; (B.K.D.P.); (R.E.P.)
- Department of Physics and Astronomy, McMaster University, ABB, 1280 Main Street West, Hamilton, ON L8S 4M1, Canada
| | - Dmitry A. Semenov
- Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany; (K.K.); (T.K.H.); (O.T.); (D.A.S.)
- Department of Chemistry, Ludwig-Maximilians-University Munich, Butenandtstr. 5-13, House F, 81377 Munich, Germany
| |
Collapse
|
15
|
Sithamparam M, Satthiyasilan N, Chen C, Jia TZ, Chandru K. A material-based panspermia hypothesis: The potential of polymer gels and membraneless droplets. Biopolymers 2022; 113:e23486. [PMID: 35148427 DOI: 10.1002/bip.23486] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 01/08/2023]
Abstract
The Panspermia hypothesis posits that either life's building blocks (molecular Panspermia) or life itself (organism-based Panspermia) may have been interplanetarily transferred to facilitate the origins of life (OoL) on a given planet, complementing several current OoL frameworks. Although many spaceflight experiments were performed in the past to test for potential terrestrial organisms as Panspermia seeds, it is uncertain whether such organisms will likely "seed" a new planet even if they are able to survive spaceflight. Therefore, rather than using organisms, using abiotic chemicals as seeds has been proposed as part of the molecular Panspermia hypothesis. Here, as an extension of this hypothesis, we introduce and review the plausibility of a polymeric material-based Panspermia seed (M-BPS) as a theoretical concept, where the type of polymeric material that can function as a M-BPS must be able to: (1) survive spaceflight and (2) "function", i.e., contingently drive chemical evolution toward some form of abiogenesis once arriving on a foreign planet. We use polymeric gels as a model example of a potential M-BPS. Polymeric gels that can be prebiotically synthesized on one planet (such as polyester gels) could be transferred to another planet via meteoritic transfer, where upon landing on a liquid bearing planet, can assemble into structures containing cellular-like characteristics and functionalities. Such features presupposed that these gels can assemble into compartments through phase separation to accomplish relevant functions such as encapsulation of primitive metabolic, genetic and catalytic materials, exchange of these materials, motion, coalescence, and evolution. All of these functions can result in the gels' capability to alter local geochemical niches on other planets, thereby allowing chemical evolution to lead to OoL events.
Collapse
Affiliation(s)
- Mahendran Sithamparam
- Space Science Center (ANGKASA), Institute of Climate Change, National University of Malaysia (UKM), Bangi, Selangor, Malaysia
| | - Nirmell Satthiyasilan
- Space Science Center (ANGKASA), Institute of Climate Change, National University of Malaysia (UKM), Bangi, Selangor, Malaysia
| | - Chen Chen
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Tony Z Jia
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan.,Blue Marble Space Institute of Science, Seattle, Washington, USA
| | - Kuhan Chandru
- Space Science Center (ANGKASA), Institute of Climate Change, National University of Malaysia (UKM), Bangi, Selangor, Malaysia
| |
Collapse
|
16
|
Abstract
One of the unique aspects of Earth is that it has a fractionally large Moon, which is thought to have formed from a Moon-forming disk generated by a giant impact. The Moon stabilizes the Earth’s spin axis at least by several degrees and contributes to Earth’s stable climate. Given that impacts are common during planet formation, exomoons, which are moons around planets in extrasolar systems, should be common as well, but no exomoon has been confirmed. Here we propose that an initially vapor-rich moon-forming disk is not capable of forming a moon that is large with respect to the size of the planet because growing moonlets, which are building blocks of a moon, experience strong gas drag and quickly fall toward the planet. Our impact simulations show that terrestrial and icy planets that are larger than ~1.3−1.6R⊕ produce entirely vapor disks, which fail to form a fractionally large moon. This indicates that (1) our model supports the Moon-formation models that produce vapor-poor disks and (2) rocky and icy exoplanets whose radii are smaller than ~1.6R⊕ are ideal candidates for hosting fractionally large exomoons. This study finds that the Moon accreted from an initially liquid-rich silicate disk and that rocky and icy exoplanets whose radii are smaller than 1.6 Earth radii are ideal candidates for hosting large exomoons.
Collapse
|
17
|
NAKAMURA E, KOBAYASHI K, TANAKA R, KUNIHIRO T, KITAGAWA H, POTISZIL C, OTA T, SAKAGUCHI C, YAMANAKA M, RATNAYAKE DM, TRIPATHI H, KUMAR R, AVRAMESCU ML, TSUCHIDA H, YACHI Y, MIURA H, ABE M, FUKAI R, FURUYA S, HATAKEDA K, HAYASHI T, HITOMI Y, KUMAGAI K, MIYAZAKI A, NAKATO A, NISHIMURA M, OKADA T, SOEJIMA H, SUGITA S, SUZUKI A, USUI T, YADA T, YAMAMOTO D, YOGATA K, YOSHITAKE M, ARAKAWA M, FUJII A, HAYAKAWA M, HIRATA N, HIRATA N, HONDA R, HONDA C, HOSODA S, IIJIMA YI, IKEDA H, ISHIGURO M, ISHIHARA Y, IWATA T, KAWAHARA K, KIKUCHI S, KITAZATO K, MATSUMOTO K, MATSUOKA M, MICHIKAMI T, MIMASU Y, MIURA A, MOROTA T, NAKAZAWA S, NAMIKI N, NODA H, NOGUCHI R, OGAWA N, OGAWA K, OKAMOTO C, ONO G, OZAKI M, SAIKI T, SAKATANI N, SAWADA H, SENSHU H, SHIMAKI Y, SHIRAI K, TAKEI Y, TAKEUCHI H, TANAKA S, TATSUMI E, TERUI F, TSUKIZAKI R, WADA K, YAMADA M, YAMADA T, YAMAMOTO Y, YANO H, YOKOTA Y, YOSHIHARA K, YOSHIKAWA M, YOSHIKAWA K, FUJIMOTO M, WATANABE SI, TSUDA Y. On the origin and evolution of the asteroid Ryugu: A comprehensive geochemical perspective. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2022; 98:227-282. [PMID: 35691845 PMCID: PMC9246647 DOI: 10.2183/pjab.98.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 05/06/2022] [Indexed: 05/28/2023]
Abstract
Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned from the C-type asteroid Ryugu by the Hayabusa2 mission. On average Ryugu particles consist of 50% phyllosilicate matrix, 41% porosity and 9% minor phases, including organic matter. The abundances of 70 elements from the particles are in close agreement with those of CI chondrites. Bulk Ryugu particles show higher δ18O, Δ17O, and ε54Cr values than CI chondrites. As such, Ryugu sampled the most primitive and least-thermally processed protosolar nebula reservoirs. Such a finding is consistent with multi-scale H-C-N isotopic compositions that are compatible with an origin for Ryugu organic matter within both the protosolar nebula and the interstellar medium. The analytical data obtained here, suggests that complex soluble organic matter formed during aqueous alteration on the Ryugu progenitor planetesimal (several 10's of km), <2.6 Myr after CAI formation. Subsequently, the Ryugu progenitor planetesimal was fragmented and evolved into the current asteroid Ryugu through sublimation.
Collapse
Affiliation(s)
- Eizo NAKAMURA
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Katsura KOBAYASHI
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Ryoji TANAKA
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Tak KUNIHIRO
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Hiroshi KITAGAWA
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Christian POTISZIL
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Tsutomu OTA
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Chie SAKAGUCHI
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Masahiro YAMANAKA
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Dilan M. RATNAYAKE
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Havishk TRIPATHI
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Rahul KUMAR
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Maya-Liliana AVRAMESCU
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Hidehisa TSUCHIDA
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Yusuke YACHI
- The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University, Misasa, Tottori, Japan
| | - Hitoshi MIURA
- Department of Information and Basic Science, Nagoya City University, Nagoya, Aichi, Japan
| | - Masanao ABE
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- The Graduate University for Advanced Studies (SOKENDAI), Hayama, Kanagawa, Japan
| | - Ryota FUKAI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Shizuho FURUYA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Kentaro HATAKEDA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Tasuku HAYASHI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Yuya HITOMI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Marine Works Japan, Ltd., Yokosuka, Kanagawa, Japan
| | - Kazuya KUMAGAI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Marine Works Japan, Ltd., Yokosuka, Kanagawa, Japan
| | - Akiko MIYAZAKI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Aiko NAKATO
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Masahiro NISHIMURA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Tatsuaki OKADA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Hiromichi SOEJIMA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Marine Works Japan, Ltd., Yokosuka, Kanagawa, Japan
| | - Seiji SUGITA
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Planetary Exploration Research Center (PERC), Chiba Institute of Technology, Narashino, Chiba, Japan
| | - Ayako SUZUKI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Marine Works Japan, Ltd., Yokosuka, Kanagawa, Japan
| | - Tomohiro USUI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Toru YADA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Daiki YAMAMOTO
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Kasumi YOGATA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Miwa YOSHITAKE
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | | | - Atsushi FUJII
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Masahiko HAYAKAWA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Naoyuki HIRATA
- Graduate School of Science, Kobe University, Kobe, Hyogo, Japan
| | - Naru HIRATA
- Faculty of Computer Science and Engineering, The University of Aizu, Aizu-Wakamatsu, Fukushima, Japan
| | - Rie HONDA
- Faculty of Science and Technology, Kochi University, Kochi, Japan
| | - Chikatoshi HONDA
- Faculty of Computer Science and Engineering, The University of Aizu, Aizu-Wakamatsu, Fukushima, Japan
| | - Satoshi HOSODA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Yu-ichi IIJIMA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Hitoshi IKEDA
- Research and Development Directorate, JAXA, Sagamihara, Kanagawa, Japan
| | - Masateru ISHIGURO
- Department of Physics and Astronomy, Seoul National University, Seoul, Korea
| | - Yoshiaki ISHIHARA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Takahiro IWATA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- The Graduate University for Advanced Studies (SOKENDAI), Hayama, Kanagawa, Japan
| | - Kosuke KAWAHARA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Shota KIKUCHI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Planetary Exploration Research Center (PERC), Chiba Institute of Technology, Narashino, Chiba, Japan
| | - Kohei KITAZATO
- Faculty of Computer Science and Engineering, The University of Aizu, Aizu-Wakamatsu, Fukushima, Japan
| | - Koji MATSUMOTO
- National Astronomical Observatory of Japan, Mitaka, Tokyo, Japan
| | - Moe MATSUOKA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Observatoire de Paris, Meudon, France
| | - Tatsuhiro MICHIKAMI
- Faculty of Engineering, Kindai University, Higashi-Hiroshima, Hiroshima, Japan
| | - Yuya MIMASU
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Akira MIURA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Tomokatsu MOROTA
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Aichi, Japan
| | - Satoru NAKAZAWA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Noriyuki NAMIKI
- National Astronomical Observatory of Japan, Mitaka, Tokyo, Japan
| | - Hirotomo NODA
- National Astronomical Observatory of Japan, Mitaka, Tokyo, Japan
| | - Rina NOGUCHI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Faculty of Science, Niigata University, Niigata, Japan
| | - Naoko OGAWA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- JAXA Space Exploration Center, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Kazunori OGAWA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Chisato OKAMOTO
- Graduate School of Science, Kobe University, Kobe, Hyogo, Japan
| | - Go ONO
- Research and Development Directorate, JAXA, Sagamihara, Kanagawa, Japan
| | - Masanobu OZAKI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Takanao SAIKI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | | | - Hirotaka SAWADA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Hiroki SENSHU
- Planetary Exploration Research Center (PERC), Chiba Institute of Technology, Narashino, Chiba, Japan
| | - Yuri SHIMAKI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Kei SHIRAI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Graduate School of Science, Kobe University, Kobe, Hyogo, Japan
| | - Yuto TAKEI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Hiroshi TAKEUCHI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Satoshi TANAKA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- The Graduate University for Advanced Studies (SOKENDAI), Hayama, Kanagawa, Japan
- The University of Tokyo, Kashiwa, Chiba, Japan
| | - Eri TATSUMI
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Instituto de Astrofisica de Canarias, University of La Laguna, Tenerife, Spain
| | - Fuyuto TERUI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Faculty of Engineering, Kanagawa Institute of Technology, Atsugi, Kanagawa, Japan
| | - Ryudo TSUKIZAKI
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Koji WADA
- Planetary Exploration Research Center (PERC), Chiba Institute of Technology, Narashino, Chiba, Japan
| | - Manabu YAMADA
- Planetary Exploration Research Center (PERC), Chiba Institute of Technology, Narashino, Chiba, Japan
| | - Tetsuya YAMADA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Yukio YAMAMOTO
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Hajime YANO
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Yasuhiro YOKOTA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Keisuke YOSHIHARA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Makoto YOSHIKAWA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- The Graduate University for Advanced Studies (SOKENDAI), Hayama, Kanagawa, Japan
| | - Kent YOSHIKAWA
- Research and Development Directorate, JAXA, Sagamihara, Kanagawa, Japan
| | - Masaki FUJIMOTO
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
| | - Sei-ichiro WATANABE
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Aichi, Japan
| | - Yuichi TSUDA
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
18
|
Worsham EA, Kleine T. Late accretionary history of Earth and Moon preserved in lunar impactites. SCIENCE ADVANCES 2021; 7:eabh2837. [PMID: 34714676 PMCID: PMC8555905 DOI: 10.1126/sciadv.abh2837] [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: 02/26/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
Late accretion describes the final addition of Earth’s mass following Moon formation and includes a period of Late Heavy Bombardment (LHB), which occurred either as a short-lived cataclysm triggered by a late giant planet orbital instability or a declining bombardment during late accretion. Using genetically characteristic ruthenium and molybdenum isotope compositions of lunar impact–derived rocks, we show that the impactors during the LHB and the entire period of late accretion were the same type of bodies and that they originated in the terrestrial planet region. Because a cataclysmic LHB would have, in part, resulted in compositionally distinct projectiles, we conclude that the LHB reflects the tail end of accretion. This implies that the giant planet orbital instability occurred during the main phase of planet formation. Last, because of their inner solar system origin, late-accreted bodies cannot be the primary source of Earth’s water.
Collapse
Affiliation(s)
- Emily A. Worsham
- Institut für Planetologie, University of Münster, Wilhelm-Klemm-Str. 10, Münster 48149, Germany
| | - Thorsten Kleine
- Institut für Planetologie, University of Münster, Wilhelm-Klemm-Str. 10, Münster 48149, Germany
| |
Collapse
|
19
|
Shi X, Castillo-Rogez J, Hsieh H, Hui H, Ip WH, Lei H, Li JY, Tosi F, Zhou L, Agarwal J, Barucci A, Beck P, Bagatin AC, Capaccioni F, Coates AJ, Cremonese G, Duffard R, Grande M, Jaumann R, Jones GH, Kallio E, Lin Y, Mousis O, Nathues A, Oberst J, Sierks H, Ulamec S, Wang M. GAUSS - genesis of asteroids and evolution of the solar system: A sample return mission to Ceres. EXPERIMENTAL ASTRONOMY 2021; 54:713-744. [PMID: 36915624 PMCID: PMC9998589 DOI: 10.1007/s10686-021-09800-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/23/2021] [Indexed: 06/18/2023]
Abstract
The goal of Project GAUSS (Genesis of Asteroids and evolUtion of the Solar System) is to return samples from the dwarf planet Ceres. Ceres is the most accessible candidate of ocean worlds and the largest reservoir of water in the inner Solar System. It shows active volcanism and hydrothermal activities in recent history. Recent evidence for the existence of a subsurface ocean on Ceres and the complex geochemistry suggest past habitability and even the potential for ongoing habitability. GAUSS will return samples from Ceres with the aim of answering the following top-level scientific questions: What is the origin of Ceres and what does this imply for the origin of water and other volatiles in the inner Solar System?What are the physical properties and internal structure of Ceres? What do they tell us about the evolutionary and aqueous alteration history of dwarf planets?What are the astrobiological implications of Ceres? Is it still habitable today?What are the mineralogical connections between Ceres and our current collections of carbonaceous meteorites?
Collapse
Affiliation(s)
- Xian Shi
- Max Planck Institute for Solar System Research, Göttingen, Germany
- Present Address: Shanghai Astronomical Observatory, Shanghai, China
| | | | | | - Hejiu Hui
- School of Earth Sciences and Engineering, Nanjing University, Nanjing, China
| | - Wing-Huen Ip
- Institute of Astronomy and Space Science, National Central University, Chung Li, Taiwan
| | - Hanlun Lei
- School of Astronomy and Space Science, Nanjing University, Nanjing, China
| | | | - Federico Tosi
- Istituto Nazionale di AstroFisica – Istituto di Astrofisica e Planetologia Spaziali (INAF-IAPS), Rome, Italy
| | - Liyong Zhou
- School of Astronomy and Space Science, Nanjing University, Nanjing, China
| | - Jessica Agarwal
- Max Planck Institute for Solar System Research, Göttingen, Germany
- Institute for Geophysics and Extraterrestrial Physics, Technical University Braunschweig, Braunschweig, Germany
| | - Antonella Barucci
- LESIA-Observatoire de Paris, Université PSL, CNRS, Université de Paris, Sorbonne Université, F-92195 Meudon, Principal Cedex, France
| | - Pierre Beck
- CNRS Institut de Planétologie et d’Astrophysique, Univ. Grenoble Alpes, Grenoble, France
| | - Adriano Campo Bagatin
- Universidad de Alicante, Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Alicante, Spain
| | - Fabrizio Capaccioni
- Istituto Nazionale di AstroFisica – Istituto di Astrofisica e Planetologia Spaziali (INAF-IAPS), Rome, Italy
| | - Andrew J. Coates
- Mullard Space Science Laboratory, University College London, Surrey, UK
| | | | - Rene Duffard
- Instituto de Astrofísica de Andalucía (CSIC), Granada, Spain
| | | | - Ralf Jaumann
- Institute of Geological Sciences, Free University of Berlin, Berlin, Germany
| | - Geraint H. Jones
- Mullard Space Science Laboratory, University College London, Surrey, UK
| | - Esa Kallio
- School of Electrical Engineering, Aalto University, Aalto, Finland
| | - Yangting Lin
- Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
| | | | - Andreas Nathues
- Max Planck Institute for Solar System Research, Göttingen, Germany
| | - Jürgen Oberst
- DLR Institute of Planetary Research, Berlin, Germany
| | - Holger Sierks
- Max Planck Institute for Solar System Research, Göttingen, Germany
| | - Stephan Ulamec
- DLR Space Operations and Astronaut Training, Cologne, Germany
| | - Mingyuan Wang
- National Astronomical Observatory, Chinese Academy of Science, Beijing, China
| | | |
Collapse
|
20
|
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.
Collapse
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
| |
Collapse
|
21
|
Mojarro A, Jin L, Szostak JW, Head JW, Zuber MT. In search of the RNA world on Mars. GEOBIOLOGY 2021; 19:307-321. [PMID: 33565260 PMCID: PMC8248371 DOI: 10.1111/gbi.12433] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 05/17/2023]
Abstract
Advances in origins of life research and prebiotic chemistry suggest that life as we know it may have emerged from an earlier RNA World. However, it has been difficult to reconcile the conditions used in laboratory experiments with real-world geochemical environments that may have existed on the early Earth and hosted the origin(s) of life. This challenge is due to geologic resurfacing and recycling that have erased the overwhelming majority of the Earth's prebiotic history. We therefore propose that Mars, a planet frozen in time, comprised of many surfaces that have remained relatively unchanged since their formation > 4 Gya, is the best alternative to search for environments consistent with geochemical requirements imposed by the RNA world. In this study, we synthesize in situ and orbital observations of Mars and modeling of its early atmosphere into solutions containing a range of pHs and concentrations of prebiotically relevant metals (Fe2+ , Mg2+ , and Mn2+ ) spanning various candidate aqueous environments. We then experimentally determine RNA degradation kinetics due to metal-catalyzed hydrolysis (cleavage) and evaluate whether early Mars could have been permissive toward the accumulation of long-lived RNA polymers. Our results indicate that a Mg2+ -rich basalt sourcing metals to a slightly acidic (pH 5.4) environment mediates the slowest rates of RNA cleavage, though geologic evidence and basalt weathering models suggest aquifers on Mars would be near neutral (pH ~ 7). Moreover, the early onset of oxidizing conditions on Mars has major consequences regarding the availability of oxygen-sensitive metals (i.e., Fe2+ and Mn2+ ) due to increased RNA degradation rates and precipitation. Overall, (a) low pH decreases RNA cleavage at high metal concentrations; (b) acidic to neutral pH environments with Fe2+ or Mn2+ cleave more RNA than Mg2+ ; and (c) alkaline environments with Mg2+ dramatically cleaves more RNA while precipitates were observed for Fe2+ and Mn2+ .
Collapse
Affiliation(s)
- Angel Mojarro
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMAUSA
| | - Lin Jin
- Department of Molecular Biology, and Center for Computational and Integrative BiologyMassachusetts General HospitalBostonMAUSA
| | - Jack W. Szostak
- Department of Molecular Biology, and Center for Computational and Integrative BiologyMassachusetts General HospitalBostonMAUSA
| | - James W. Head
- Department of Earth, Environmental and Planetary SciencesBrown UniversityProvidenceRIUSA
| | - Maria T. Zuber
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMAUSA
| |
Collapse
|
22
|
Goodrich CA, Sanborn ME, Yin QZ, Kohl I, Frank D, Daly RT, Walsh KJ, Zolensky ME, Young ERD, Jenniskens P, Shaddad MH. Chromium Isotopic Evidence for Mixing of NC and CC Reservoirs in Polymict Ureilites: Implications for Dynamical Models of the Early Solar System. THE PLANETARY SCIENCE JOURNAL 2021; 2:13. [PMID: 33681766 PMCID: PMC7931809 DOI: 10.3847/psj/abd258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nucleosynthetic isotope anomalies show that the first few million years of solar system history were characterized by two distinct cosmochemical reservoirs, CC (carbonaceous chondrites and related differentiated meteorites) and NC (the terrestrial planets and all other groups of chondrites and differentiated meteorites), widely interpreted to correspond to the outer and inner solar system, respectively. At some point, however, bulk CC and NC materials became mixed, and several dynamical models offer explanations for how and when this occurred. We use xenoliths of CC materials in polymict ureilite (NC) breccias to test the applicability of such models. Polymict ureilites represent regolith on ureilitic asteroids but contain carbonaceous chondrite-like xenoliths. We present the first 54Cr isotope data for such clasts, which, combined with oxygen and hydrogen isotopes, show that they are unique CC materials that became mixed with NC materials in these breccias. It has been suggested that such xenoliths were implanted into ureilites by outer solar system bodies migrating into the inner solar system during the gaseous disk phase ~3-5 Myr after CAI, as in the "Grand Tack" model. However, combined textural, petrologic, and spectroscopic observations suggest that they were added to ureilitic regolith at ~50-60 Myr after CAI, along with ordinary, enstatite, and Rumuruti-type chondrites, as a result of breakup of multiple parent bodies in the asteroid belt at this time. This is consistent with models for an early instability of the giant planets. The C-type asteroids from which the xenoliths were derived were already present in inner solar system orbits.
Collapse
Affiliation(s)
- Cyrena A Goodrich
- Lunar and Planetary Institute, Universities Space Research Association, 3600 Bay Area Blvd, Houston, TX 77058 USA
| | - Matthew E Sanborn
- Department of Earth and Planetary Sciences, University of California at Davis, Davis, CA 95616 USA
| | - Qing-Zhu Yin
- Department of Earth and Planetary Sciences, University of California at Davis, Davis, CA 95616 USA
| | - Issaku Kohl
- Department of Earth and Planetary Sciences, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095 USA
| | - David Frank
- Hawai'i Institute of Geophysics and Planetology, Department of Earth Sciences, University of Hawai'i at Mānoa, Honolulu HI 96822 USA
| | - R Terik Daly
- The Johns Hopkins University Applied Physics Laboratory 11100 Johns Hopkins Road
| | - Kevin J Walsh
- Southwest Research Institute, 1050 Walnut St. Suite 300, Boulder, CO 80302 USA
| | - Michael E Zolensky
- Astromaterials Research and Exploration Science, NASA-Johnson Space Center Houston, TX 77058 USA
| | - Edward R D Young
- Department of Earth and Planetary Sciences, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095 USA
| | | | - Muawia H Shaddad
- Physics Department, University of Khartoum, Khartoum 11115 Sudan
| |
Collapse
|
23
|
The origin of the Moon's Earth-like tungsten isotopic composition from dynamical and geochemical modeling. Nat Commun 2021; 12:35. [PMID: 33397911 PMCID: PMC7782809 DOI: 10.1038/s41467-020-20266-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 11/05/2020] [Indexed: 11/16/2022] Open
Abstract
The Earth and Moon have identical or very similar isotopic compositions for many elements, including tungsten. However, canonical models of the Moon-forming impact predict that the Moon should be made mostly of material from the impactor, Theia. Here we evaluate the probability of the Moon inheriting its Earth-like tungsten isotopes from Theia in the canonical giant impact scenario, using 242 N-body models of planetary accretion and tracking tungsten isotopic evolution, and find that this probability is <1.6–4.7%. Mixing in up to 30% terrestrial materials increases this probability, but it remains <10%. Achieving similarity in stable isotopes is also a low-probability outcome, and is controlled by different mechanisms than tungsten. The Moon’s stable isotopes and tungsten isotopic composition are anticorrelated due to redox effects, lowering the joint probability to significantly less than 0.08–0.4%. We therefore conclude that alternate explanations for the Moon’s isotopic composition are likely more plausible. Tungsten isotopes between the Earth and Moon are compared in this new study. The authors find that traditional models of Moon formation are very unlikely to reproduce the Moon's Earth-like isotopic composition.
Collapse
|
24
|
Lunar impact crater identification and age estimation with Chang'E data by deep and transfer learning. Nat Commun 2020; 11:6358. [PMID: 33353954 PMCID: PMC7755906 DOI: 10.1038/s41467-020-20215-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 11/11/2020] [Indexed: 11/09/2022] Open
Abstract
Impact craters, which can be considered the lunar equivalent of fossils, are the most dominant lunar surface features and record the history of the Solar System. We address the problem of automatic crater detection and age estimation. From initially small numbers of recognized craters and dated craters, i.e., 7895 and 1411, respectively, we progressively identify new craters and estimate their ages with Chang’E data and stratigraphic information by transfer learning using deep neural networks. This results in the identification of 109,956 new craters, which is more than a dozen times greater than the initial number of recognized craters. The formation systems of 18,996 newly detected craters larger than 8 km are estimated. Here, a new lunar crater database for the mid- and low-latitude regions of the Moon is derived and distributed to the planetary community together with the related data analysis. Using Chang’E data, the authors here identify more than 109,000 previously unrecognized lunar craters and date almost 19,000 craters based on transfer learning with deep neural networks. A new lunar crater database is derived and distributed to the planetary community.
Collapse
|
25
|
The internal structure and geodynamics of Mars inferred from a 4.2-Gyr zircon record. Proc Natl Acad Sci U S A 2020; 117:30973-30979. [PMID: 33199613 PMCID: PMC7733809 DOI: 10.1073/pnas.2016326117] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We discovered a zircon record in a Martian meteorite that spans 4.2 Gyr, nearly the entire geologic history of Mars. Ancient zircons define a bimodal distribution with groupings at 4474 ± 10 Ma and 4442 ± 17 Ma, reflecting intense bombardment episodes triggered by the migration of the gas giant planets. A group of younger detrital zircons record ages from 1548.0 ± 8.8 Ma to 299.5 ± 0.6 Ma. The only plausible sources for these grains are the Elysium and Tharsis volcanic provinces that are the expressions of deep-seated mantle plumes. The chondritic-like Hf-isotope compositions of these zircons require the existence of a primitive and convecting mantle reservoir. Thus, these grains provide a tangible record of the deep Martian interior. Combining U–Pb ages with Lu–Hf data in zircon provides insights into the magmatic history of rocky planets. The Northwest Africa (NWA) 7034/7533 meteorites are samples of the southern highlands of Mars containing zircon with ages as old as 4476.3 ± 0.9 Ma, interpreted to reflect reworking of the primordial Martian crust by impacts. We extracted a statistically significant zircon population (n = 57) from NWA 7533 that defines a temporal record spanning 4.2 Gyr. Ancient zircons record ages from 4485.5 ± 2.2 Ma to 4331.0 ± 1.4 Ma, defining a bimodal distribution with groupings at 4474 ± 10 Ma and 4442 ± 17 Ma. We interpret these to represent intense bombardment episodes at the planet’s surface, possibly triggered by the early migration of gas giant planets. The unradiogenic initial Hf-isotope composition of these zircons establishes that Mars’s igneous activity prior to ∼4.3 Ga was limited to impact-related reworking of a chemically enriched, primordial crust. A group of younger detrital zircons record ages from 1548.0 ± 8.8 Ma to 299.5 ± 0.6 Ma. The only plausible sources for these grains are the temporally associated Elysium and Tharsis volcanic provinces that are the expressions of deep-seated mantle plumes. The chondritic-like Hf-isotope compositions of these zircons require the existence of a primitive and convecting mantle reservoir, indicating that Mars has been in a stagnant-lid tectonic regime for most of its history. Our results imply that zircon is ubiquitous on the Martian surface, providing a faithful record of the planet’s magmatic history.
Collapse
|
26
|
Parker RJ. The birth environment of planetary systems. ROYAL SOCIETY OPEN SCIENCE 2020; 7:201271. [PMID: 33391806 PMCID: PMC7735350 DOI: 10.1098/rsos.201271] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 10/29/2020] [Indexed: 06/12/2023]
Abstract
Star and planet formation are inextricably linked. In the earliest phases of the collapse of a protostar, a disc forms around the young star and such discs are observed for the first several million years of a star's life. It is within these circumstellar, or protoplanetary, discs that the first stages of planet formation occur. Recent observations from the Atacama large millimetre array (ALMA) suggest that planet formation may already be underway after only 1 Myr of a star's life. However, stars do not form in isolation; they form from the collapse and fragmentation of giant molecular clouds several parsecs in size. This results in young stars forming in groups-often referred to as 'clusters'. In these star-forming regions, the stellar density is much higher than the location of the Sun and other stars in the Galactic disc that host exoplanets. As such, the environment where stars form has the potential to influence the planet formation process. In star-forming regions, protoplanetary discs can be truncated or destroyed by interactions with passing stars, as well as photoevaporation from the radiation fields of very massive stars. Once formed, the planets themselves can have their orbits altered by dynamical encounters-either directly from passing stars or through secondary effects such as the Kozai-Lidov mechanism. In this contribution, I review the different processes that can affect planet formation and stability in star-forming regions. I discuss each process in light of the typical range of stellar densities observed for star-forming regions. I finish by discussing these effects in the context of theories for the birth environment of the Solar System.
Collapse
|
27
|
Zellner NEB, McCaffrey VP, Butler JHE. Cometary Glycolaldehyde as a Source of pre-RNA Molecules. ASTROBIOLOGY 2020; 20:1377-1388. [PMID: 32985898 DOI: 10.1089/ast.2020.2216] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Over 200 molecules have been detected in multiple extraterrestrial environments, including glycolaldehyde (C2(H2O)2, GLA), a two-carbon sugar precursor that has been detected in regions of the interstellar medium. Its recent in situ detection on the nucleus of comet 67P/Churyumov-Gerasimenko and through remote observations in the comae of others provides tantalizing evidence that it is common on most (if not all) comets. Impact experiments conducted at the Experimental Impact Laboratory at NASA's Johnson Space Center have shown that samples of GLA and GLA mixed with montmorillonite clays can survive impact delivery in the pressure range of 4.5 to 25 GPa. Extrapolated to amounts of GLA observed on individual comets and assuming a monotonic impact rate in the first billion years of Solar System history, these experimental results show that up to 1023 kg of cometary GLA could have survived impact delivery, with substantial amounts of threose, erythrose, glycolic acid, and ethylene glycol also produced or delivered. Importantly, independent of the profile of the impact flux in the early Solar System, comet delivery of GLA would have provided (and may continue to provide) a reservoir of starting material for the formose reaction (to form ribose) and the Strecker reaction (to form amino acids). Thus, comets may have been important delivery vehicles for starting molecules necessary for life as we know it.
Collapse
Affiliation(s)
| | | | - Jayden H E Butler
- Department of Physics, Albion College, Albion, Michigan, USA
- Department of Physics, California State University - Los Angeles, Los Angeles, California, USA
| |
Collapse
|
28
|
Rubin M, Engrand C, Snodgrass C, Weissman P, Altwegg K, Busemann H, Morbidelli A, Mumma M. On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko. SPACE SCIENCE REVIEWS 2020; 216:102. [PMID: 32801398 PMCID: PMC7392949 DOI: 10.1007/s11214-020-00718-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 07/03/2020] [Indexed: 06/02/2023]
Abstract
Primitive objects like comets hold important information on the material that formed our solar system. Several comets have been visited by spacecraft and many more have been observed through Earth- and space-based telescopes. Still our understanding remains limited. Molecular abundances in comets have been shown to be similar to interstellar ices and thus indicate that common processes and conditions were involved in their formation. The samples returned by the Stardust mission to comet Wild 2 showed that the bulk refractory material was processed by high temperatures in the vicinity of the early sun. The recent Rosetta mission acquired a wealth of new data on the composition of comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) and complemented earlier observations of other comets. The isotopic, elemental, and molecular abundances of the volatile, semi-volatile, and refractory phases brought many new insights into the origin and processing of the incorporated material. The emerging picture after Rosetta is that at least part of the volatile material was formed before the solar system and that cometary nuclei agglomerated over a wide range of heliocentric distances, different from where they are found today. Deviations from bulk solar system abundances indicate that the material was not fully homogenized at the location of comet formation, despite the radial mixing implied by the Stardust results. Post-formation evolution of the material might play an important role, which further complicates the picture. This paper discusses these major findings of the Rosetta mission with respect to the origin of the material and puts them in the context of what we know from other comets and solar system objects.
Collapse
Affiliation(s)
- Martin Rubin
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
| | - Cécile Engrand
- CNRS/IN2P3, IJCLab, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Colin Snodgrass
- Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ UK
| | | | - Kathrin Altwegg
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
| | - Henner Busemann
- Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH Zurich, Zurich, Switzerland
| | | | - Michael Mumma
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd., Greenbelt, 20771 MD USA
| |
Collapse
|
29
|
Rodriguez JAP, Dobrea EN, Kargel JS, Baker VR, Crown DA, Webster KD, Berman DC, Wilhelm MB, Buckner D. The Oldest Highlands of Mars May Be Massive Dust Fallout Deposits. Sci Rep 2020; 10:10347. [PMID: 32587301 PMCID: PMC7316829 DOI: 10.1038/s41598-020-64676-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 04/14/2020] [Indexed: 11/17/2022] Open
Abstract
The oldest terrains of Mars are cratered landscapes, in which extensive valleys and basins are covered by ubiquitous fluvial plains. One current paradigm maintains that an impact-generated megaregolith underlies these sediments. This megaregolith was likely largely generated during the Early Noachian (~4.1 to ~3.94 Ga) when most Martian impact basins formed. We examined the geologic records of NW Hellas and NW Isidis, which include this epoch’s most extensive circum-basin outcrops. Here, we show that these regions include widespread, wind-eroded landscapes, crater rims eroded down by several hundred meters, pitted plains, and inverted fluvial and crater landforms. These surfaces exhibit few fresh craters, indicating geologically recent wind erosion. The deep erosion, topographic inversions, and an absence of dunes on or near talus across these regions suggest that sediments finer than sand compose most of these highland materials. We propose that basin-impact-generated hurricane-force winds created sediment-laden atmospheric conditions, and that muddy rains rapidly settled suspended sediments to construct extensive Early Noachian highlands. The implied high abundance of fine-grained sediments before these impacts suggests large-scale glacial silt production and supports the previously proposed Noachian “icy highlands” hypothesis. We suggest that subglacial meltwater interactions with the sedimentary highlands could have promoted habitability, particularly in clay strata.
Collapse
Affiliation(s)
- J Alexis P Rodriguez
- Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ, 85719-2395, USA.
| | - Eldar Noe Dobrea
- Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ, 85719-2395, USA
| | - Jeffrey S Kargel
- Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ, 85719-2395, USA
| | - V R Baker
- Department of Hydrology & Atmospheric Sciences, University of Arizona, Tucson, AZ, 85721, USA
| | - David A Crown
- Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ, 85719-2395, USA
| | - Kevin D Webster
- Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ, 85719-2395, USA
| | - Daniel C Berman
- Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ, 85719-2395, USA
| | | | - Denise Buckner
- University of North Dakota, Department of Space Studies, Grand Forks, ND, 58202, USA.,Blue Marble Space Institute of Science, 1001 4th Ave, Suite 3201, Seattle, WA, 98154, USA
| |
Collapse
|
30
|
New HST data and modeling reveal a massive planetesimal collision around Fomalhaut. Proc Natl Acad Sci U S A 2020; 117:9712-9722. [PMID: 32312810 DOI: 10.1073/pnas.1912506117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The apparent detection of an exoplanet orbiting Fomalhaut was announced in 2008. However, subsequent observations of Fomalhaut b raised questions about its status: Unlike other exoplanets, it is bright in the optical and nondetected in the infrared, and its orbit appears to cross the debris ring around the star without the expected gravitational perturbations. We revisit previously published data and analyze additional Hubble Space Telescope (HST) data, finding that the source is likely on a radial trajectory and has faded and become extended. Dynamical and collisional modeling of a recently produced dust cloud yields results consistent with the observations. Fomalhaut b appears to be a directly imaged catastrophic collision between two large planetesimals in an extrasolar planetary system. Similar events should be very rare in quiescent planetary systems of the age of Fomalhaut, suggesting that we are possibly witnessing the effects of gravitational stirring due to the orbital evolution of hypothetical planet(s) around the star.
Collapse
|
31
|
Bekaert DV, Broadley MW, Marty B. The origin and fate of volatile elements on Earth revisited in light of noble gas data obtained from comet 67P/Churyumov-Gerasimenko. Sci Rep 2020; 10:5796. [PMID: 32242104 PMCID: PMC7118078 DOI: 10.1038/s41598-020-62650-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 03/17/2020] [Indexed: 11/25/2022] Open
Abstract
The origin of terrestrial volatiles remains one of the most puzzling questions in planetary sciences. The timing and composition of chondritic and cometary deliveries to Earth has remained enigmatic due to the paucity of reliable measurements of cometary material. This work uses recently measured volatile elemental ratios and noble gas isotope data from comet 67P/Churyumov-Gerasimenko (67P/C-G), in combination with chondritic data from the literature, to reconstruct the composition of Earth’s ancient atmosphere. Comets are found to have contributed ~20% of atmospheric heavy noble gases (i.e., Kr and Xe) but limited amounts of other volatile elements (water, halogens and likely organic materials) to Earth. These cometary noble gases were likely mixed with chondritic - and not solar - sources to form the atmosphere. We show that an ancient atmosphere composed of chondritic and cometary volatiles is more enriched in Xe relative to the modern atmosphere, requiring that 8–12 times the present-day inventory of Xe was lost to space. This potentially resolves the long-standing mystery of Earth’s “missing xenon”, with regards to both Xe elemental depletion and isotopic fractionation in the atmosphere. The inferred Kr/H2O and Xe/H2O of the initial atmosphere suggest that Earth’s surface volatiles might not have been fully delivered by the late accretion of volatile-rich carbonaceous chondrites. Instead, “dry” materials akin to enstatite chondrites potentially constituted a significant source of chondritic volatiles now residing on the Earth’s surface. We outline the working hypotheses, implications and limitations of this model in the last section of this contribution.
Collapse
Affiliation(s)
- David V Bekaert
- Centre de Recherches Pétrographiques et Géochimiques, UMR 7358 CNRS - Université de Lorraine, 15 rue Notre Dame des Pauvres, BP 20, 54501, Vandoeuvre-lès-Nancy, France.
| | - Michael W Broadley
- Centre de Recherches Pétrographiques et Géochimiques, UMR 7358 CNRS - Université de Lorraine, 15 rue Notre Dame des Pauvres, BP 20, 54501, Vandoeuvre-lès-Nancy, France.
| | - Bernard Marty
- Centre de Recherches Pétrographiques et Géochimiques, UMR 7358 CNRS - Université de Lorraine, 15 rue Notre Dame des Pauvres, BP 20, 54501, Vandoeuvre-lès-Nancy, France
| |
Collapse
|
32
|
Caselli P. Our astrochemical origins. Phys Life Rev 2020; 32:117-118. [DOI: 10.1016/j.plrev.2019.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 08/19/2019] [Indexed: 10/26/2022]
|
33
|
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.
Collapse
|
34
|
|
35
|
Rubin M, Engrand C, Snodgrass C, Weissman P, Altwegg K, Busemann H, Morbidelli A, Mumma M. On the Origin and Evolution of the Material in 67P/Churyumov-Gerasimenko. SPACE SCIENCE REVIEWS 2020. [PMID: 32801398 DOI: 10.1007/s11214-019-0625-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Primitive objects like comets hold important information on the material that formed our solar system. Several comets have been visited by spacecraft and many more have been observed through Earth- and space-based telescopes. Still our understanding remains limited. Molecular abundances in comets have been shown to be similar to interstellar ices and thus indicate that common processes and conditions were involved in their formation. The samples returned by the Stardust mission to comet Wild 2 showed that the bulk refractory material was processed by high temperatures in the vicinity of the early sun. The recent Rosetta mission acquired a wealth of new data on the composition of comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) and complemented earlier observations of other comets. The isotopic, elemental, and molecular abundances of the volatile, semi-volatile, and refractory phases brought many new insights into the origin and processing of the incorporated material. The emerging picture after Rosetta is that at least part of the volatile material was formed before the solar system and that cometary nuclei agglomerated over a wide range of heliocentric distances, different from where they are found today. Deviations from bulk solar system abundances indicate that the material was not fully homogenized at the location of comet formation, despite the radial mixing implied by the Stardust results. Post-formation evolution of the material might play an important role, which further complicates the picture. This paper discusses these major findings of the Rosetta mission with respect to the origin of the material and puts them in the context of what we know from other comets and solar system objects.
Collapse
Affiliation(s)
- Martin Rubin
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
| | - Cécile Engrand
- CNRS/IN2P3, IJCLab, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Colin Snodgrass
- Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, EH9 3HJ UK
| | | | - Kathrin Altwegg
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
| | - Henner Busemann
- Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH Zurich, Zurich, Switzerland
| | | | - Michael Mumma
- NASA Goddard Space Flight Center, 8800 Greenbelt Rd., Greenbelt, 20771 MD USA
| |
Collapse
|
36
|
Lin Y, van Westrenen W. Isotopic evidence for volatile replenishment of the Moon during the Late Accretion. Natl Sci Rev 2019; 6:1247-1254. [PMID: 34692002 PMCID: PMC8291620 DOI: 10.1093/nsr/nwz033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/18/2019] [Accepted: 03/08/2019] [Indexed: 11/12/2022] Open
Abstract
The traditional view of a dry, volatile-poor Moon has been challenged by the identification of water and other volatiles in lunar samples, but the volatile budget delivery time(s), source(s) and temporal evolution remain poorly constrained. Here we show that hydrogen and chlorine isotopic ratios in lunar apatite changed significantly during the Late Accretion (LA, 4.1-3.8 billion years ago). During this period, deuterium/hydrogen ratios in the Moon changed from initial carbonaceous-chondrite-like values to values consistent with an influx of ordinary-chondrite-like material and pre-LA elevated δ37Cl values drop towards lower chondrite-like values. Inferred pre-LA lunar interior water contents are significantly lower than pristine values suggesting degassing, followed by an increase during the LA. These trends are consistent with dynamic models of solar-system evolution, suggesting that the Moon's (and Earth's) initial volatiles were replenished ∼0.5 Ga after their formation, with their final budgets reflecting a mixture of sources and delivery times.
Collapse
Affiliation(s)
- Yanhao Lin
- Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam 1081 HV, The Netherlands
| | - Wim van Westrenen
- Department of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam 1081 HV, The Netherlands
| |
Collapse
|
37
|
Mitra S. Percolation clusters of organics in interstellar ice grains as the incubators of life. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 149:33-38. [PMID: 31647939 DOI: 10.1016/j.pbiomolbio.2019.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 09/30/2019] [Accepted: 10/16/2019] [Indexed: 12/15/2022]
Abstract
Biomolecules can be synthesized in interstellar ice grains subject to UV radiation and cosmic rays. I show that on time scales of ≳106 years, these processes lead to the formation of large percolation clusters of organic molecules. Some of these clusters would have ended up on proto-planets where large, loosely bound aggregates of clusters (superclusters) would have formed. The interior regions of such superclusters provided for chemical micro-environments that are filtered versions of the outside environment. I argue that models for abiogenesis are more likely to work when considered inside such micro-environments. As the supercluster breaks up, biochemical systems in such micro-environments gradually become subject to a less filtered environment, allowing them to get adapted to the more complex outside environment. A particular system originating from a particular location on some supercluster would have been the first to get adapted to the raw outside environment and survive there, thereby becoming the first microbe. A collision of a microbe-containing proto-planet with the Moon could have led to fragments veering off back into space, microbes in small fragments would have been able to survive a subsequent impact with the Earth.
Collapse
Affiliation(s)
- Saibal Mitra
- Oostendestraat 14, 4433 AK, Hoedekenskerke, the Netherlands.
| |
Collapse
|
38
|
Volcanic history in the Smythii basin based on SELENE radar observation. Sci Rep 2019; 9:14502. [PMID: 31601828 PMCID: PMC6787070 DOI: 10.1038/s41598-019-50296-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 09/05/2019] [Indexed: 11/17/2022] Open
Abstract
Elucidation of the subsurface structure in the Smythii basin on the moon is important for understanding lunar volcanic history. Two lava units (Units 1 and 2) cover this basin. The spatial subsurface structure below Unit 2 is unknown. We used SELENE/Lunar Radar Sounder data to identify four subsurface boundaries at 130, 190, 300, and 420 m depths. The radar is reflected at the paleo-regolith layer sandwiched among lava flows, which is supported by a simple radar reflection/transmission model. The spatial distribution of subsurface boundaries demonstrates the deposition of Unit 2 on the subsidence in Unit 1. A simple loading model explained the maximum depth of subsidence (~500 m) and indicated that lithospheric thickness in the Smythii basin was ~24 km at 3.95 Gya. The estimated growth rate of the lithosphere was ~60 km/Ga during 3.95 to 3.07 Gya. After the formation of the Smythii basin at ~4.11 Gya, Unit 1 and Unit 2 deposited with eruption rates of ~8.4 × 10−4 km3/yr by 3.95 Gya and ~7.5 × 10−6 km3/yr by 3.07 Gya respectively. The timing of decline in volcanic activity in the Smythii basin differs from that for the lunar nearside maria, indicating the diversity of volcanism in various lunar areas.
Collapse
|
39
|
Mojarro A, Hachey J, Bailey R, Brown M, Doebler R, Ruvkun G, Zuber MT, Carr CE. Nucleic Acid Extraction and Sequencing from Low-Biomass Synthetic Mars Analog Soils for In Situ Life Detection. ASTROBIOLOGY 2019; 19:1139-1152. [PMID: 31204862 PMCID: PMC6708270 DOI: 10.1089/ast.2018.1929] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Recent studies regarding the origins of life and Mars-Earth meteorite transfer simulations suggest that biological informational polymers, such as nucleic acids (DNA and RNA), have the potential to provide unambiguous evidence of life on Mars. To this end, we are developing a metagenomics-based life-detection instrument which integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG). Our goal is to isolate and sequence nucleic acids from extant or preserved life on Mars in order to determine if a particular genetic sequence (1) is distantly related to life on Earth, indicating a shared ancestry due to lithological exchange, or (2) is unrelated to life on Earth, suggesting convergent origins of life on Mars. In this study, we validate prior work on nucleic acid extraction from cells deposited in Mars analog soils down to microbial concentrations (i.e., 104 cells in 50 mg of soil) observed in the driest and coldest regions on Earth. In addition, we report low-input nanopore sequencing results from 2 pg of purified Bacillus subtilis spore DNA simulating ideal extraction yields equivalent to 1 ppb life-detection sensitivity. We achieve this by employing carrier sequencing, a method of sequencing sub-nanogram DNA in the background of a genomic carrier. After filtering of carrier, low-quality, and low-complexity reads we detected 5 B. subtilis reads, 18 contamination reads (including Homo sapiens), and 6 high-quality noise reads believed to be sequencing artifacts.
Collapse
Affiliation(s)
- Angel Mojarro
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts
- Address correspondence to: Angel Mojarro, Massachusetts Institute of Technology, 77 Massachusetts Ave, Room E25-647, Cambridge, MA 02139
| | | | - Ryan Bailey
- Claremont Biosolutions, LLC, Upland, California
| | - Mark Brown
- Claremont Biosolutions, LLC, Upland, California
| | | | - Gary Ruvkun
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts
| | - Maria T. Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Christopher E. Carr
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts
| |
Collapse
|
40
|
|
41
|
Abstract
The analysis of lunar samples returned to Earth by the Apollo and Luna missions changed our view of the processes involved in planet formation. The data obtained on lunar samples brought to light the importance during planet growth of highly energetic collisions that lead to global-scale melting. This violent birth determines the initial structure and long-term evolution of planets. Once past its formative era, the lunar surface has served as a recorder of more than 4 billion years of interaction with the space environment. The chronologic record of lunar cratering determined from the returned samples underpins age estimates for planetary surfaces throughout the inner Solar System and provides evidence of the dynamic nature of the Solar System during the planet-forming era.
Collapse
Affiliation(s)
- Richard W Carlson
- Department of Terrestrial Magnetism, Carnegie Institution for Science, Washington, DC 20015, USA
| |
Collapse
|
42
|
History of the Terminal Cataclysm Paradigm: Epistemology of a Planetary Bombardment That Never (?) Happened. GEOSCIENCES 2019. [DOI: 10.3390/geosciences9070285] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study examines the history of the paradigm concerning a lunar (or solar-systemwide)terminal cataclysm (also called “Late Heavy Bombardment” or LHB), a putative, brief spikein impacts at ~3.9 Ga ago, preceded by low impact rates. We examine origin of the ideas, why theywere accepted, and why the ideas are currently being seriously revised, if not abandoned. Thepaper is divided into the following sections:1. Overview of paradigm.2. Pre-Apollo views (1949-1969).3. Initial suggestions of cataclysm (ca. 1974).4. Ironies.5. Alternative suggestions, megaregolith evolution (1970s).6. Impact melt rocks “establish” cataclysm (1990).7. Imbrium redux (ca. 1998).8. Impact melt clasts (early 2000s).9. Dating of front-side lunar basins?10. Dynamical models “explain” the cataclysm (c. 2000s).11. Asteroids as a test case.12. Impact melts predating 4.0 Ga ago (ca. 2008-present.).13. Biological issues.14. Growing doubts (ca. 1994-2014).15. Evolving Dynamical Models (ca. 2001-present).16. Connections to lunar origin.17. Dismantling the paradigm (2015-2018).18. “Megaregolith Evolution Model” for explaining the data.19. Conclusions and new directions for future work.The author hopes that this open-access discussion may prove useful for classroom discussionsof how science moves forward through self-correction of hypotheses.
Collapse
|
43
|
Singer KN, McKinnon WB, Gladman B, Greenstreet S, Bierhaus EB, Stern SA, Parker AH, Robbins SJ, Schenk PM, Grundy WM, Bray VJ, Beyer RA, Binzel RP, Weaver HA, Young LA, Spencer JR, Kavelaars JJ, Moore JM, Zangari AM, Olkin CB, Lauer TR, Lisse CM, Ennico K. Impact craters on Pluto and Charon indicate a deficit of small Kuiper belt objects. Science 2019; 363:955-959. [PMID: 30819958 DOI: 10.1126/science.aap8628] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 02/05/2019] [Indexed: 11/02/2022]
Abstract
The flyby of Pluto and Charon by the New Horizons spacecraft provided high-resolution images of cratered surfaces embedded in the Kuiper belt, an extensive region of bodies orbiting beyond Neptune. Impact craters on Pluto and Charon were formed by collisions with other Kuiper belt objects (KBOs) with diameters from ~40 kilometers to ~300 meters, smaller than most KBOs observed directly by telescopes. We find a relative paucity of small craters ≲13 kilometers in diameter, which cannot be explained solely by geological resurfacing. This implies a deficit of small KBOs (≲1 to 2 kilometers in diameter). Some surfaces on Pluto and Charon are likely ≳4 billion years old, thus their crater records provide information on the size-frequency distribution of KBOs in the early Solar System.
Collapse
|
44
|
Quarles B, Kaib N. Instabilities in the Early Solar System due to a Self-gravitating Disk. THE ASTRONOMICAL JOURNAL 2019; 157:67. [PMID: 31534266 PMCID: PMC6750231 DOI: 10.3847/1538-3881/aafa71] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Modern studies of the early solar system routinely invoke the possibility of an orbital instability among the giant planets triggered by gravitational interactions between the planets and a massive exterior disk of planetesimals. Previous works have suggested that this instability can be substantially delayed (~100s Myr) after the formation of the giant planets. Bodies in the disk are typically treated in a semi-active manner, wherein their gravitational force on the planets is included, but interactions between the planetesimals are ignored. We perform N-body numerical simulations using GENGA, which makes use of GPUs to allow for the inclusion of all gravitational interactions between bodies. Although our simulated Kuiper belt particles are more massive than the probable masses of real primordial Kuiper belt objects, our simulations indicate that the self-stirring of the primordial Kuiper belt is very important to the dynamics of the giant planet instability. We find that interactions between planetesimals dynamically heat the disk and typically prevent the outer solar system instability from being delayed by more than a few tens of million years after giant planet formation. Longer delays occur in a small fraction of systems that have at least 3.5 AU gaps between the planets and planetesimal disk. Our final planetary configurations match the solar system at a rate consistent with other previous works in most regards. Pre-instability heating of the disk typically yields final Jovian eccentricities comparable to the modern solar system value, which has been a difficult constraint to match in past works.
Collapse
Affiliation(s)
- B Quarles
- HL Dodge Department of Physics & Astronomy, University of Oklahoma, Norman, OK 73019, USA
| | - N Kaib
- HL Dodge Department of Physics & Astronomy, University of Oklahoma, Norman, OK 73019, USA
| |
Collapse
|
45
|
Shimamura K, Shimojo F, Nakano A, Tanaka S. Ab initio molecular dynamics study of prebiotic production processes of organic compounds at meteorite impacts on ocean. J Comput Chem 2019; 40:349-359. [PMID: 30306615 DOI: 10.1002/jcc.25606] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 02/05/2023]
Abstract
Recent experiments concerning prebiotic materials syntheses suggest that the iron-bearing meteorite impacts on ocean during Late Heavy Bombardment provided abundant organic compounds associated with biomolecules such as amino acids and nucleobases. However, the molecular mechanism of a series of chemical reactions to produce such compounds is not well understood. In this study, we simulate the shock compression state of a meteorite impact for a model system composed of CO2 , H2 O, and metallic iron slab by ab initio molecular dynamics combined with multiscale shock technique, and clarify possible elementary reaction processes up to production of organic compounds. The reactions included not only pathways similar to the Fischer-Tropsch process known as an important hydrocarbon synthesis in many planetary processes but also those resulting in production of a carboxylic acid. It is also found that bicarbonate ions formed from CO2 and H2 O participated in some forms in most of these observed elementary reaction processes. These findings would deepen the understanding of the full range of chemical reactions that could occur in the meteorite impact events. © 2018 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Kohei Shimamura
- Graduate School of System Informatics, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan
| | - Fuyuki Shimojo
- Department of Physics, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan
| | - Aiichiro Nakano
- Collaboratory for Advanced Computing and Simulations, Department of Physics & Astronomy, Department of Computer Science, Department of Chemical Engineering & Materials Science, and Department of Biological Sciences, University of Southern California, Los Angeles, California, 90089-0242
| | - Shigenori Tanaka
- Graduate School of System Informatics, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe, 657-8501, Japan
| |
Collapse
|
46
|
|
47
|
Demography in the Big Data Revolution: Changing the Culture to Forge New Frontiers. POPULATION RESEARCH AND POLICY REVIEW 2018. [DOI: 10.1007/s11113-018-9464-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
48
|
Pearce BKD, Tupper AS, Pudritz RE, Higgs PG. Constraining the Time Interval for the Origin of Life on Earth. ASTROBIOLOGY 2018; 18:343-364. [PMID: 29570409 DOI: 10.1089/ast.2017.1674] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Estimates of the time at which life arose on Earth make use of two types of evidence. First, astrophysical and geophysical studies provide a timescale for the formation of Earth and the Moon, for large impact events on early Earth, and for the cooling of the early magma ocean. From this evidence, we can deduce a habitability boundary, which is the earliest point at which Earth became habitable. Second, biosignatures in geological samples, including microfossils, stromatolites, and chemical isotope ratios, provide evidence for when life was actually present. From these observations we can deduce a biosignature boundary, which is the earliest point at which there is clear evidence that life existed. Studies with molecular phylogenetics and records of the changing level of oxygen in the atmosphere give additional information that helps to determine the biosignature boundary. Here, we review the data from a wide range of disciplines to summarize current information on the timings of these two boundaries. The habitability boundary could be as early as 4.5 Ga, the earliest possible estimate of the time at which Earth had a stable crust and hydrosphere, or as late as 3.9 Ga, the end of the period of heavy meteorite bombardment. The lack of consensus on whether there was a late heavy meteorite bombardment that was significant enough to prevent life is the largest uncertainty in estimating the time of the habitability boundary. The biosignature boundary is more closely constrained. Evidence from carbon isotope ratios and stromatolite fossils both point to a time close to 3.7 Ga. Life must have emerged in the interval between these two boundaries. The time taken for life to appear could, therefore, be within 200 Myr or as long as 800 Myr. Key Words: Origin of life-Astrobiology-Habitability-Biosignatures-Geochemistry-Early Earth. Astrobiology 18, 343-364.
Collapse
Affiliation(s)
- Ben K D Pearce
- Origins Institute, Department of Physics and Astronomy, McMaster University , Hamilton, Canada
| | - Andrew S Tupper
- Origins Institute, Department of Physics and Astronomy, McMaster University , Hamilton, Canada
| | - Ralph E Pudritz
- Origins Institute, Department of Physics and Astronomy, McMaster University , Hamilton, Canada
| | - Paul G Higgs
- Origins Institute, Department of Physics and Astronomy, McMaster University , Hamilton, Canada
| |
Collapse
|
49
|
|
50
|
The California-KeplerSurvey. V. Peas in a Pod: Planets in aKeplerMulti-planet System Are Similar in Size and Regularly Spaced. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-3881/aa9ff6] [Citation(s) in RCA: 186] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|