1
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Vance SD, Craft KL, Shock E, Schmidt BE, Lunine J, Hand KP, McKinnon WB, Spiers EM, Chivers C, Lawrence JD, Wolfenbarger N, Leonard EJ, Robinson KJ, Styczinski MJ, Persaud DM, Steinbrügge G, Zolotov MY, Quick LC, Scully JEC, Becker TM, Howell SM, Clark RN, Dombard AJ, Glein CR, Mousis O, Sephton MA, Castillo-Rogez J, Nimmo F, McEwen AS, Gudipati MS, Jun I, Jia X, Postberg F, Soderlund KM, Elder CM. Investigating Europa's Habitability with the Europa Clipper. SPACE SCIENCE REVIEWS 2023; 219:81. [PMID: 38046182 PMCID: PMC10687213 DOI: 10.1007/s11214-023-01025-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 11/03/2023] [Indexed: 12/05/2023]
Abstract
The habitability of Europa is a property within a system, which is driven by a multitude of physical and chemical processes and is defined by many interdependent parameters, so that its full characterization requires collaborative investigation. To explore Europa as an integrated system to yield a complete picture of its habitability, the Europa Clipper mission has three primary science objectives: (1) characterize the ice shell and ocean including their heterogeneity, properties, and the nature of surface-ice-ocean exchange; (2) characterize Europa's composition including any non-ice materials on the surface and in the atmosphere, and any carbon-containing compounds; and (3) characterize Europa's geology including surface features and localities of high science interest. The mission will also address several cross-cutting science topics including the search for any current or recent activity in the form of thermal anomalies and plumes, performing geodetic and radiation measurements, and assessing high-resolution, co-located observations at select sites to provide reconnaissance for a potential future landed mission. Synthesizing the mission's science measurements, as well as incorporating remote observations by Earth-based observatories, the James Webb Space Telescope, and other space-based resources, to constrain Europa's habitability, is a complex task and is guided by the mission's Habitability Assessment Board (HAB).
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Affiliation(s)
- Steven D. Vance
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Kathleen L. Craft
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD USA
| | - Everett Shock
- School of Earth & Space Exploration and School of Molecular Sciences, Arizona State University, Tempe, AZ USA
| | - Britney E. Schmidt
- Department of Astronomy and Department of Earth & Atmospheric Sciences, Cornell University, Ithaca, NY USA
| | - Jonathan Lunine
- Department of Astronomy and Department of Earth & Atmospheric Sciences, Cornell University, Ithaca, NY USA
| | - Kevin P. Hand
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - William B. McKinnon
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University in St. Louis, Saint Louis, MO USA
| | - Elizabeth M. Spiers
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
| | - Chase Chivers
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
- Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA USA
| | - Justin D. Lawrence
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA USA
- Honeybee Robotics, Altadena, CA USA
| | - Natalie Wolfenbarger
- Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, TX USA
| | - Erin J. Leonard
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | | | | | - Divya M. Persaud
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Gregor Steinbrügge
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Mikhail Y. Zolotov
- School of Earth & Space Exploration and School of Molecular Sciences, Arizona State University, Tempe, AZ USA
| | | | | | | | - Samuel M. Howell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | | | - Andrew J. Dombard
- Dept. of Earth and Environmental Sciences, University of Illinois Chicago, Chicago, USA
| | | | - Olivier Mousis
- Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
| | - Mark A. Sephton
- Impacts and Astromaterials Research Centre, Department of Earth Science and Engineering, Imperial College London, London, United Kingdom
| | | | - Francis Nimmo
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA USA
| | - Alfred S. McEwen
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ USA
| | - Murthy S. Gudipati
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Insoo Jun
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - Xianzhe Jia
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI USA
| | - Frank Postberg
- Institut für Geologische Wissenschaften, Freie Universität Berlin, Berlin, Germany
| | - Krista M. Soderlund
- Institute for Geophysics, John A. and Katherine G. Jackson School of Geosciences, University of Texas at Austin, Austin, TX USA
| | - Catherine M. Elder
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
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2
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Borlina CS, Weiss BP, Bryson JFJ, Bai XN, Lima EA, Chatterjee N, Mansbach EN. Paleomagnetic evidence for a disk substructure in the early solar system. SCIENCE ADVANCES 2021; 7:eabj6928. [PMID: 34652938 PMCID: PMC8519560 DOI: 10.1126/sciadv.abj6928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 08/25/2021] [Indexed: 06/02/2023]
Abstract
Astronomical observations and isotopic measurements of meteorites suggest that substructures are common in protoplanetary disks and may even have existed in the solar nebula. Here, we conduct paleomagnetic measurements of chondrules in CO carbonaceous chondrites to investigate the existence and nature of these disk substructures. We show that the paleomagnetism of chondrules in CO carbonaceous chondrites indicates the presence of a 101 ± 48 μT field in the solar nebula in the outer solar system (~3 to 7 AU from the Sun). The high intensity of this field relative to that inferred from inner solar system (~<3 AU) meteorites indicates a factor of ~5 to 150 mismatch in nebular accretion between the two reservoirs. This suggests substantial mass loss from the disk associated with a major disk substructure, possibly due to a magnetized disk wind.
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Affiliation(s)
- Cauê S. Borlina
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Benjamin P. Weiss
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Xue-Ning Bai
- Institute for Advanced Study and Department of Astronomy, Tsinghua University, Beijing, China
| | - Eduardo A. Lima
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Nilanjan Chatterjee
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Elias N. Mansbach
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
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3
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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?
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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
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4
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Wang K, Li W, Li S, Tian Z, Koefoed P, Zheng XY. Geochemistry and Cosmochemistry of Potassium Stable Isotopes. CHEMIE DER ERDE : BEITRAGE ZUR CHEMISCHEN MINERALOGIE, PETROGRAPHIE UND GEOLOGIE 2021; 81:125786. [PMID: 35001939 PMCID: PMC8740523 DOI: 10.1016/j.chemer.2021.125786] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Stable potassium isotopes are one of the emerging non-traditional isotope systems enabled in recent years by the advance of Multi-Collector Inductively-Coupled-Plasma Mass-Spectrometry (MC-ICP-MS). In this review, we first summarize the geochemical and cosmochemical properties of K, its major reservoirs, and the analytical methods of K isotopes. Following this, we review recent literature on K isotope applications in the fields of geochemistry and cosmochemistry. Geochemically, K is a highly incompatible lithophile element, and a highly soluble, biophile element. The isotopic fractionation of K is relatively small during magmatic processes such as partial melting and fractional crystallization, whereas during low-temperature and biological processes fractionation is considerably larger. This resolvable fractionation has made K isotopes promising tracers for a variety of Earth and environmental processes, including chemical weathering, low-temperature alteration of igneous rocks, reverse weathering, and the recycling of sediments into the mantle during subduction. Sorption and interactions of aqueous K with different clay minerals during cation exchange and clay formation are likely to be of fundamental significance in generating much of the K isotope variability seen in samples from the Earth surface and samples carrying recycled surface materials from the deep Earth. The magnitude of this fractionation is process- and mineral-dependent. Comprehensive quantification of pertinent K isotope fractionation factors is currently lacking and urgently needed. Significant fractionation during biological activities, such as plant uptake, demonstrates the potential utility of K isotopes in the study of the nutrient cycle and its relation to the climate and various ecosystems, enabling new and largely unexplored avenues for future research. Of significant importance to the cosmochemistry community, K is a moderately volatile element with large variations in K/U ratio observed among chondrites and planetary materials. As this indicates different degrees of volatile depletion, it has become a fundamental chemical signature of both chondritic and planetary bodies. This volatile depletion has been attributed to various processes such as solar nebula condensation, mixing of volatile-rich and -poor reservoirs, planetary accretional volatilization via impacts, and/or magma ocean degassing. While K isotopes have the potential to distinguish these different processes, the current results are still highly debated. A good correlation between the K isotope compositions of four differentiated bodies (Earth, Mars, Moon, and Vesta) and their masses suggests a ubiquitous volatile depletion mechanism during the formation of the terrestrial planets. It is still unknown whether any of the K isotopic variation among chondrites and differentiated bodies can be attributed to inherited signatures of mass-independent isotopic anomalies.
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Affiliation(s)
- Kun Wang
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University in St. Louis, MO 63130, USA
| | - Weiqiang Li
- School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Shilei Li
- School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Zhen Tian
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University in St. Louis, MO 63130, USA
| | - Piers Koefoed
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University in St. Louis, MO 63130, USA
| | - Xin-Yuan Zheng
- Department of Earth and Environmental Sciences, University of Minnesota - Twin Cities, Minneapolis, MN 55455, USA
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5
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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.
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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
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6
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Lichtenberg T, Dra Żkowska J, Schönbächler M, Golabek GJ, Hands TO. Bifurcation of planetary building blocks during Solar System formation. Science 2021; 371:365-370. [PMID: 33479146 DOI: 10.1126/science.abb3091] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 12/10/2020] [Indexed: 11/02/2022]
Abstract
Geochemical and astronomical evidence demonstrates that planet formation occurred in two spatially and temporally separated reservoirs. The origin of this dichotomy is unknown. We use numerical models to investigate how the evolution of the solar protoplanetary disk influenced the timing of protoplanet formation and their internal evolution. Migration of the water snow line can generate two distinct bursts of planetesimal formation that sample different source regions. These reservoirs evolve in divergent geophysical modes and develop distinct volatile contents, consistent with constraints from accretion chronology, thermochemistry, and the mass divergence of inner and outer Solar System. Our simulations suggest that the compositional fractionation and isotopic dichotomy of the Solar System was initiated by the interplay between disk dynamics, heterogeneous accretion, and internal evolution of forming protoplanets.
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Affiliation(s)
- Tim Lichtenberg
- Atmospheric, Oceanic and Planetary Physics, Department of Physics, University of Oxford, Oxford, UK.
| | - Joanna Dra Żkowska
- University Observatory, Faculty of Physics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Maria Schönbächler
- Institute for Geochemistry and Petrology, Department of Earth Sciences, ETH Zurich, Zurich, Switzerland
| | - Gregor J Golabek
- Bayerisches Geoinstitut, University of Bayreuth, Bayreuth, Germany
| | - Thomas O Hands
- Institute for Computational Science, University of Zurich, Zurich, Switzerland
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7
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Burbine TH, Greenwood RC. Exploring the Bimodal Solar System via Sample Return from the Main Asteroid Belt: The Case for Revisiting Ceres. SPACE SCIENCE REVIEWS 2020; 216:59. [PMID: 32624627 PMCID: PMC7319314 DOI: 10.1007/s11214-020-00671-0] [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: 07/24/2019] [Accepted: 04/07/2020] [Indexed: 06/11/2023]
Abstract
Sample return from a main-belt asteroid has not yet been attempted, but appears technologically feasible. While the cost implications are significant, the scientific case for such a mission appears overwhelming. As suggested by the "Grand Tack" model, the structure of the main belt was likely forged during the earliest stages of Solar System evolution in response to migration of the giant planets. Returning samples from the main belt has the potential to test such planet migration models and the related geochemical and isotopic concept of a bimodal Solar System. Isotopic studies demonstrate distinct compositional differences between samples believed to be derived from the outer Solar System (CC or carbonaceous chondrite group) and those that are thought to be derived from the inner Solar System (NC or non-carbonaceous group). These two groups are separated on relevant isotopic variation diagrams by a clear compositional gap. The interface between these two regions appears to be broadly coincident with the present location of the asteroid belt, which contains material derived from both groups. The Hayabusa mission to near-Earth asteroid (NEA) (25143) Itokawa has shown what can be learned from a sample-return mission to an asteroid, even with a very small amount of sample. One scenario for main-belt sample return involves a spacecraft launching a projectile that strikes an object and flying through the debris cloud, which would potentially allow multiple bodies to be sampled if a number of projectiles are used on different asteroids. Another scenario is the more traditional method of landing on an asteroid to obtain the sample. A significant range of main-belt asteroids are available as targets for a sample-return mission and such a mission would represent a first step in mineralogically and isotopically mapping the asteroid belt. We argue that a sample-return mission to the asteroid belt does not necessarily have to return material from both the NC and CC groups to viably test the bimodal Solar System paradigm, as material from the NC group is already abundantly available for study. Instead, there is overwhelming evidence that we have a very incomplete suite of CC-related samples. Based on our analysis, we advocate a dedicated sample-return mission to the dwarf planet (1) Ceres as the best means of further exploring inherent Solar System variation. Ceres is an ice-rich world that may be a displaced trans-Neptunian object. We almost certainly do not have any meteorites that closely resemble material that would be brought back from Ceres. The rich heritage of data acquired by the Dawn mission makes a sample-return mission from Ceres logistically feasible at a realistic cost. No other potential main-belt target is capable of providing as much insight into the early Solar System as Ceres. Such a mission should be given the highest priority by the international scientific community.
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Affiliation(s)
- Thomas H. Burbine
- Department of Astronomy, Mount Holyoke College, South Hadley, MA 01075 USA
| | - Richard C. Greenwood
- Planetary and Space Sciences, School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA UK
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8
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Ogliore RC, Palma RL, Stodolna J, Nagashima K, Pepin RO, Schlutter D, Gainsforth Z, Westphal AJ, Huss GR. Q-gases in a late-forming refractory interplanetary dust particle: A link to comet Wild 2. GEOCHIMICA ET COSMOCHIMICA ACTA 2020; 271:116-131. [PMID: 32214433 PMCID: PMC7094769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report the structure, chemical composition, O, Al-Mg, He, and Ne isotope systematics of an interplanetary dust particle, "Manchanito". These analyses indicate that Manchanito solidified as refractory glass (with oxidized Fe but reduced Ti) in a chondrule-like formation environment more than 3.2 Myr after CAIs, after which it was exposed to Q-like noble gases in the dissipating solar nebula. Manchanito's He and Ne isotopic composition and concentrations are similar to those measured in samples of comet Wild 2, from which we infer that Manchanito's parent body was a comet. We propose that after formation and exposure to Q-like gases, Manchanito was transported to the outer Solar System where it came into contact with organics and volatile ices on its cometary parent body. Manchanito provides additional evidence that cometary solids have been subjected to energetic processing and large-scale transport in a wide range of environments in the Solar System.
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Affiliation(s)
- Ryan C. Ogliore
- Department of Physics, Washington University in St. Louis,
St. Louis, MO 63130, United States
| | | | | | - Kazuhide Nagashima
- Hawai‘i Institute of Geophysics and Planetology,
University of Hawai‘i at Mānoa, Honolulu, HI 96822, United
States
| | | | | | - Zack Gainsforth
- Space Sciences Laboratory, University of California at
Berkeley, United States
| | - Andrew J. Westphal
- Space Sciences Laboratory, University of California at
Berkeley, United States
| | - Gary R. Huss
- Hawai‘i Institute of Geophysics and Planetology,
University of Hawai‘i at Mānoa, Honolulu, HI 96822, United
States
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9
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Goodrich CA, Zolensky ME, Fioretti AM, Shaddad MH, Downes H, Hiroi T, Kohl I, Young ED, Kita NT, Hamilton VE, Riebe MEI, Busemann H, Macke RJ, Fries M, Ross DK, Jenniskens P. The First Samples from Almahata Sitta Showing Contacts Between Ureilitic and Chondritic Lithologies: Implications for the Structure and Composition of Asteroid 2008 TC 3. METEORITICS & PLANETARY SCIENCE 2019; 54:2769-2813. [PMID: 33716489 PMCID: PMC7954227 DOI: 10.1111/maps.13390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 08/17/2019] [Indexed: 06/12/2023]
Abstract
Almahata Sitta (AhS), an anomalous polymict ureilite, is the first meteorite observed to originate from a spectrally classified asteroid (2008 TC3). However, correlating properties of the meteorite with those of the asteroid is not straightforward because the AhS stones are diverse types. Of those studied prior to this work, 70-80% are ureilites (achondrites) and 20-30% are various types of chondrites. Asteroid 2008 TC3 was a heterogeneous breccia that disintegrated in the atmosphere, with its clasts landing on Earth as individual stones and most of its mass lost. We describe AhS 91A and AhS 671, which are the first AhS stones to show contacts between ureilitic and chondritic materials and provide direct information about the structure and composition of asteroid 2008 TC3. AhS 91A and AhS 671 are friable breccias, consisting of a C1 lithology that encloses rounded to angular clasts (<10 μm to 3 mm) of olivine, pyroxenes, plagioclase, graphite, and metal-sulfide, as well as chondrules (~130-600 μm) and chondrule fragments. The C1 material consists of fine-grained phyllosilicates (serpentine and saponite) and amorphous material, magnetite, breunnerite, dolomite, fayalitic olivine (Fo 28-42), an unidentified Ca-rich silicate phase, Fe,Ni sulfides, and minor Ca-phosphate and ilmenite. It has similarities to CI1 but shows evidence of heterogeneous thermal metamorphism. Its bulk oxygen isotope composition (δ18O = 13.53‰, δ17O = 8.93‰) is unlike that of any known chondrite, but similar to compositions of several CC-like clasts in typical polymict ureilites. Its Cr isotope composition is unlike that of any known meteorite. The enclosed clasts and chondrules do not belong to the C1 lithology. The olivine (Fo 75-88), pyroxenes (pigeonite of Wo ~10 and orthopyroxene of Wo ~4.6), plagioclase, graphite, and some metal-sulfide are ureilitic, based on mineral compositions, textures, and oxygen isotope compositions, and represent at least six distinct ureilitic lithologies. The chondrules are probably derived from type 3 OC and/or CC, based on mineral and oxygen isotope compositions. Some of the metal-sulfide clasts are derived from EC. AhS 91A and AhS 671 are plausible representatives of the bulk of the asteroid that was lost. Reflectance spectra of AhS 91A are dark (reflectance ~0.04-0.05) and relatively featureless in VNIR, and have an ~2.7 μm absorption band due to OH- in phyllosilicates. Spectral modeling, using mixtures of laboratory VNIR reflectance spectra of AhS stones to fit the F-type spectrum of the asteroid, suggests that 2008 TC3 consisted mainly of ureilitic and AhS 91A-like materials, with as much as 40-70% of the latter, and <10% of OC, EC and other meteorite types. The bulk density of AhS 91A (2.35 ± 0.05 g/cm3) is lower than bulk densities of other AhS stones, and closer to estimates for the asteroid (~1.7-2.2 g/cm3). Its porosity (36%) is near the low end of estimates for the asteroid (33-50%), suggesting significant macroporosity. The textures of AhS 91A and AhS 671 (finely comminuted clasts of disparate materials intimately mixed) support formation of 2008 TC3 in a regolith environment. AhS 91A and AhS 671 could represent a volume of regolith formed when a CC-like body impacted into already well-gardened ureilitic + impactor-derived debris. AhS 91A bulk samples do not show a solar wind (SW) component, so they represent sub-surface layers. AhS 91A has a lower cosmic ray exposure (CRE) age (~5-9 Ma) than previously studied AhS stones (11-22 Ma). The spread in CRE ages argues for irradiation in a regolith environment. AhS 91A and AhS 671 show that ureilitic asteroids could have detectable ~2.7 μm absorption bands.
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Affiliation(s)
- Cyrena Anne Goodrich
- Lunar and Planetary Institute, Universities Space Research Association, 3600 Bay Area Blvd, Houston, TX 77058 USA
| | - Michael E Zolensky
- Astromaterials Research and Exploration Science, NASA-Johnson Space Center Houston, TX 77058 USA
| | | | - Muawia H Shaddad
- Physics Department, University of Khartoum, Khartoum 11115 Sudan
| | - Hilary Downes
- Department of Earth and Planetary Sciences, Birkbeck, University of London, Malet Street, Bloomsbury, London WC1E 7HX UK
| | - Takahiro Hiroi
- Department of Geological Sciences, Brown University, Providence, RI 02912, 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
| | - Edward D Young
- Department of Earth and Planetary Sciences, University of California at Los Angeles, 595 Charles Young Drive East, Los Angeles, CA 90095 USA
| | - Noriko T Kita
- Wisc-SIMS Laboratory, Department of Geoscience, University of Wisconsin-Madison, 1215 West Dayton Street, Madison, WI 53706 USA
| | - Victoria E Hamilton
- Department of Space Studies, Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder Colorado 80302 USA
| | - My E I Riebe
- Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Rd NW, Washington, DC 20015, USA
- Institute for Geochemistry and Petrology, ETH Zürich, Clausiusstrasse 25, CH-8092 Zürich, Switzerland
| | - Henner Busemann
- Institute for Geochemistry and Petrology, ETH Zürich, Clausiusstrasse 25, CH-8092 Zürich, Switzerland
| | | | - M Fries
- Astromaterials Research and Exploration Science, NASA-Johnson Space Center Houston, TX 77058 USA
| | - D Kent Ross
- Jacobs-JETS, University of Texas at El Paso, at NASA-JSC, Houston, TX 77058 USA
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Krot AN. CHONDRITES AND THEIR COMPONENTS: RECORDS OF EARLY SOLAR SYSTEM PROCESSES. METEORITICS & PLANETARY SCIENCE 2019; 54:1647-1691. [PMID: 31379423 PMCID: PMC6677159 DOI: 10.1111/maps.13350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 06/06/2019] [Indexed: 06/10/2023]
Abstract
AbstractChondrites consist of three major components: refractory inclusions (Ca,Al‐rich inclusions [CAIs] and amoeboid olivine aggregates), chondrules, and matrix. Here, I summarize recent results on the mineralogy, petrology, oxygen, and aluminum‐magnesium isotope systematics of the chondritic components (mainly CAIs in carbonaceous chondrites) and their significance for understanding processes in the protoplanetary disk (PPD) and on chondrite parent asteroids. CAIs are the oldest solids originated in the solar system: their U‐corrected Pb‐Pb absolute age of 4567.3 ± 0.16 Ma is considered to represent time 0 of its evolution. CAIs formed by evaporation, condensation, and aggregation in a gas of approximately solar composition in a hot (ambient temperature >1300 K) disk region exposed to irradiation by solar energetic particles, probably near the protoSun; subsequently, some CAIs were melted in and outside their formation region during transient heating events of still unknown nature. In unmetamorphosed, type 2–3.0 chondrites, CAIs show large variations in the initial 26Al/27Al ratios, from <5 × 10–6 to ~5.25 × 10–5. These variations and the inferred low initial abundance of 60Fe in the PPD suggest late injection of 26Al by a wind from a nearby Wolf–Rayet star into the protosolar molecular cloud core prior to or during its collapse. Although there are multiple generations of CAIs characterized by distinct mineralogies, textures, and isotopic (O, Mg, Ca, Ti, Mo, etc.) compositions, the 26Al heterogeneity in the CAI‐forming region(s) precludes determining the duration of CAIs formation using 26Al‐26Mg systematics. The existence of multiple generations of CAIs and the observed differences in CAI abundances in carbonaceous and noncarbonaceous chondrites may indicate that CAIs were episodically formed and ejected by a disk wind from near the Sun to the outer solar system and then spiraled inward due to gas drag. In type 2–3.0 chondrites, most CAIs surrounded by Wark–Lovering rims have uniform Δ17O (= δ17O−0.52 × δ18O) of ~ −24‰; however, there is a large range of Δ17O (from ~−40 to ~ −5‰) among them, suggesting the coexistence of 16O‐rich (low Δ17O) and 16O‐poor (high Δ17O) gaseous reservoirs at the earliest stages of the PPD evolution. The observed variations in Δ17O of CAIs may be explained if three major O‐bearing species in the solar system (CO, H2O, and silicate dust) had different O‐isotope compositions, with H2O and possibly silicate dust being 16O‐depleted relative to both the Genesis solar wind Δ17O of −28.4 ± 3.6‰ and even more 16O‐enriched CO. Oxygen isotopic compositions of CO and H2O could have resulted from CO self‐shielding in the protosolar molecular cloud (PMC) and the outer PPD. The nature of 16O‐depleted dust at the earliest stages of PPD evolution remains unclear: it could have either been inherited from the PMC or the initially 16O‐rich (solar‐like) MC dust experienced O‐isotope exchange during thermal processing in the PPD. To understand the chemical and isotopic composition of the protosolar MC material and the degree of its thermal processing in PPD, samples of the primordial silicates and ices, which may have survived in the outer solar system, are required. In metamorphosed CO3 and CV3 chondrites, most CAIs exhibit O‐isotope heterogeneity that often appears to be mineralogically controlled: anorthite, melilite, grossite, krotite, perovskite, and Zr‐ and Sc‐rich oxides and silicates are 16O‐depleted relative to corundum, hibonite, spinel, Al,Ti‐diopside, forsterite, and enstatite. In texturally fine‐grained CAIs with grain sizes of ~10–20 μm, this O‐isotope heterogeneity is most likely due to O‐isotope exchange with 16O‐poor (Δ17O ~0‰) aqueous fluids on the CO and CV chondrite parent asteroids. In CO3.1 and CV3.1 chondrites, this process did not affect Al‐Mg isotope systematics of CAIs. In some coarse‐grained igneous CV CAIs, O‐isotope heterogeneity of anorthite, melilite, and igneously zoned Al,Ti‐diopside appears to be consistent with their crystallization from melts of isotopically evolving O‐isotope compositions. These CAIs could have recorded O‐isotope exchange during incomplete melting in nebular gaseous reservoir(s) with different O‐isotope compositions and during aqueous fluid–rock interaction on the CV asteroid.
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The Effect of Jupiter's Formation on the Distribution of Refractory Elements and Inclusions in Meteorites. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-4365/aad95f] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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