1
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Castillo‐Rogez J, Weiss B, Beddingfield C, Biersteker J, Cartwright R, Goode A, Melwani Daswani M, Neveu M. Compositions and Interior Structures of the Large Moons of Uranus and Implications for Future Spacecraft Observations. JOURNAL OF GEOPHYSICAL RESEARCH. PLANETS 2023; 128:e2022JE007432. [PMID: 37034459 PMCID: PMC10078161 DOI: 10.1029/2022je007432] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 11/29/2022] [Accepted: 12/02/2022] [Indexed: 06/19/2023]
Abstract
The five large moons of Uranus are important targets for future spacecraft missions. To motivate and inform the exploration of these moons, we model their internal evolution, present-day physical structures, and geochemical and geophysical signatures that may be measured by spacecraft. We predict that if the moons preserved liquid until present, it is likely in the form of residual oceans less than 30 km thick in Ariel, Umbriel, and less than 50 km in Titania, and Oberon. The preservation of liquid strongly depends on material properties and, potentially, on dynamical circumstances that are presently unknown. Miranda is unlikely to host liquid at present unless it experienced tidal heating a few tens of million years ago. We find that since the thin residual layers may be hypersaline, their induced magnetic fields could be detectable by future spacecraft-based magnetometers. However, if the ocean is maintained primarily by ammonia, and thus well below the water freezing point, then its electrical conductivity may be too small to be detectable by spacecraft. Lastly, our calculated tidal Love number (k 2) and dissipation factor (Q) are consistent with the Q/k 2 values previously inferred from dynamical evolution models. In particular, we find that the low Q/k 2 estimated for Titania supports the hypothesis that Titania currently holds an ocean.
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Affiliation(s)
| | - Benjamin Weiss
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of Technology (MIT)CambridgeMAUSA
| | - Chloe Beddingfield
- SETI InstituteMountain ViewCAUSA
- NASA Ames Research CenterMountain ViewCAUSA
| | - John Biersteker
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of Technology (MIT)CambridgeMAUSA
| | | | - Allison Goode
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of Technology (MIT)CambridgeMAUSA
| | | | - Marc Neveu
- University of MarylandCollege ParkMDUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
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2
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Formation of Comets. UNIVERSE 2022. [DOI: 10.3390/universe8070381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Questions regarding how primordial or pristine the comets of the solar system are have been an ongoing controversy. In this review, we describe comets’ physical evolution from dust and ice grains in the solar nebula to the contemporary small bodies in the outer solar system. This includes the phases of dust agglomeration, the formation of planetesimals, their thermal evolution and the outcomes of collisional processes. We use empirical evidence about comets, in particular from the Rosetta Mission to comet 67P/Churyumov–Gerasimenko, to draw conclusions about the possible thermal and collisional evolution of comets.
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3
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Melwani Daswani M, Vance SD, Mayne MJ, Glein CR. A Metamorphic Origin for Europa's Ocean. GEOPHYSICAL RESEARCH LETTERS 2021; 48:e2021GL094143. [PMID: 35865189 PMCID: PMC9286408 DOI: 10.1029/2021gl094143] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 07/26/2021] [Accepted: 08/04/2021] [Indexed: 05/28/2023]
Abstract
Europa likely contains an iron-rich metal core. For it to have formed, temperatures within Europa reached ≳ 1250 K. Going up to that temperature, accreted chondritic minerals - for example, carbonates and phyllosilicates - would partially devolatilize. Here, we compute the amounts and compositions of exsolved volatiles. We find that volatiles released from the interior would have carried solutes, redox-sensitive species, and could have generated a carbonic ocean in excess of Europa's present-day hydrosphere, and potentially an early CO 2 atmosphere. No late delivery of cometary water was necessary. Contrasting with prior work, CO 2 could be the most abundant solute in the ocean, followed by Ca 2 + , SO 4 2 - , and HCO 3 - . However, gypsum precipitation going from the seafloor to the ice shell decreases the dissolved S/Cl ratio, such that Cl > S at the shallowest depths, consistent with recently inferred endogenous chlorides at Europa's surface. Gypsum would form a 3-10 km thick sedimentary layer at the seafloor.
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Affiliation(s)
| | - Steven D. Vance
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Matthew J. Mayne
- Department of Earth SciencesStellenbosch UniversityStellenboschSouth Africa
| | - Christopher R. Glein
- Space Science and Engineering DivisionSouthwest Research InstituteSan AntonioTXUSA
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4
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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.
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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
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5
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O'Rourke L, Heinisch P, Blum J, Fornasier S, Filacchione G, Van Hoang H, Ciarniello M, Raponi A, Gundlach B, Blasco RA, Grieger B, Glassmeier KH, Küppers M, Rotundi A, Groussin O, Bockelée-Morvan D, Auster HU, Oklay N, Paar G, Perucha MDPC, Kovacs G, Jorda L, Vincent JB, Capaccioni F, Biver N, Parker JW, Tubiana C, Sierks H. The Philae lander reveals low-strength primitive ice inside cometary boulders. Nature 2020; 586:697-701. [PMID: 33116289 DOI: 10.1038/s41586-020-2834-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 08/28/2020] [Indexed: 11/09/2022]
Abstract
On 12 November 2014, the Philae lander descended towards comet 67P/Churyumov-Gerasimenko, bounced twice off the surface, then arrived under an overhanging cliff in the Abydos region. The landing process provided insights into the properties of a cometary nucleus1-3. Here we report an investigation of the previously undiscovered site of the second touchdown, where Philae spent almost two minutes of its cross-comet journey, producing four distinct surface contacts on two adjoining cometary boulders. It exposed primitive water ice-that is, water ice from the time of the comet's formation 4.5 billion years ago-in their interiors while travelling through a crevice between the boulders. Our multi-instrument observations made 19 months later found that this water ice, mixed with ubiquitous dark organic-rich material, has a local dust/ice mass ratio of [Formula: see text], matching values previously observed in freshly exposed water ice from outbursts4 and water ice in shadow5,6. At the end of the crevice, Philae made a 0.25-metre-deep impression in the boulder ice, providing in situ measurements confirming that primitive ice has a very low compressive strength (less than 12 pascals, softer than freshly fallen light snow) and allowing a key estimation to be made of the porosity (75 ± 7 per cent) of the boulders' icy interiors. Our results provide constraints for cometary landers seeking access to a volatile-rich ice sample.
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Affiliation(s)
- Laurence O'Rourke
- European Space Agency (ESA), European Space Astronomy Centre (ESAC), Madrid, Spain.
| | - Philip Heinisch
- Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany
| | - Jürgen Blum
- Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany
| | - Sonia Fornasier
- LESIA, Observatoire de Paris, Université PSL, CNRS, Université de Paris, Sorbonne Université, Meudon, France.,Institut Universitaire de France (IUF), Paris, France
| | - Gianrico Filacchione
- Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy
| | - Hong Van Hoang
- LESIA, Observatoire de Paris, Université PSL, CNRS, Université de Paris, Sorbonne Université, Meudon, France.,Université Grenoble Alpes, CNRS, Institut de Planétologie et Astrophysique de Grenoble (IPAG), UMR, Grenoble, France
| | - Mauro Ciarniello
- Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy
| | - Andrea Raponi
- Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy
| | - Bastian Gundlach
- Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany
| | - Rafael Andrés Blasco
- Telespazio Vega UK Ltd for the European Space Agency (ESA), European Space Astronomy Centre (ESAC), Madrid, Spain
| | - Björn Grieger
- Aurora Technology BV for the European Space Agency (ESA), European Space Astronomy Centre (ESAC), Madrid, Spain
| | - Karl-Heinz Glassmeier
- Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany
| | - Michael Küppers
- European Space Agency (ESA), European Space Astronomy Centre (ESAC), Madrid, Spain
| | - Alessandra Rotundi
- Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy.,Dipartimento di Scienze e Tecnologie, Universitá degli Studi di Napoli Parthenope, Naples, Italy
| | | | - Dominique Bockelée-Morvan
- LESIA, Observatoire de Paris, Université PSL, CNRS, Université de Paris, Sorbonne Université, Meudon, France
| | - Hans-Ulrich Auster
- Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Braunschweig, Germany
| | | | - Gerhard Paar
- Joanneum Research Forschungsgesellschaft, Graz, Austria
| | | | - Gabor Kovacs
- Department of Mechatronics, Optics and Engineering Informatics, Budapest University of Technology and Economics, Budapest, Hungary
| | - Laurent Jorda
- Aix Marseille Université, CNRS, CNES, LAM, Marseille, France
| | | | - Fabrizio Capaccioni
- Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy
| | - Nicolas Biver
- LESIA, Observatoire de Paris, Université PSL, CNRS, Université de Paris, Sorbonne Université, Meudon, France
| | - Joel Wm Parker
- Planetary Science Directorate, Southwest Research Institute (SwRI), Boulder, CO, USA
| | - Cecilia Tubiana
- Istituto Nazionale di Astrofisica, Istituto di Astrofisica e Planetologia Spaziali, Rome, Italy.,Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany
| | - Holger Sierks
- Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany
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6
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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.
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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
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7
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Franceschi M, Penasa L, Massironi M, Naletto G, Ferrari S, Fondriest M, Bodewits D, Güttler C, Lucchetti A, Mottola S, Pajola M, Toth I, Deller J, Sierks H, Tubiana C. Global-scale brittle plastic rheology at the cometesimals merging of comet 67P/Churyumov-Gerasimenko. Proc Natl Acad Sci U S A 2020; 117:10181-10187. [PMID: 32341151 PMCID: PMC7229685 DOI: 10.1073/pnas.1914552117] [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] [Indexed: 11/18/2022] Open
Abstract
Observations of comet nuclei indicate that the main constituent is a mix of ice and refractory materials characterized by high porosity (70-75%) and low bulk strength (10-4-10-6 MPa); however, the nature and physical properties of these materials remain largely unknown. By combining surface inspection of comet 67P/Churyumov-Gerasimenko and three-dimensional (3D) modeling of the independent concentric sets of layers that make up the structure of its two lobes, we provide clues about the large-scale rheological behavior of the nucleus and the kinematics of the impact that originated it. Large folds in the layered structure indicate that the merging of the two cometesimals involved reciprocal motion with dextral strike-slip kinematics that bent the layers in the contact area without obliterating them. Widespread long cracks and the evidence of relevant mass loss in absence of large density variations within the comet's body testify that large-scale deformation occurred in a brittle-plastic regime and was accommodated through folding and fracturing. Comparison of refined 3D geologic models of the lobes with triaxial ellipsoids that suitably represent the overall layers arrangement reveals characteristics that are consistent with an impact between two roughly ellipsoidal cometesimals that produced large-scale axial compression and transversal elongation. The observed features imply global transfer of impact-related shortening into transversal strain. These elements delineate a model for the global rheology of cometesimals that could be possible evoking a prominent bonding action of ice and, to a minor extent, organics.
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Affiliation(s)
- Marco Franceschi
- Department of Mathematics and Geosciences, University of Trieste, 34128 Trieste, Italy;
- Department of Geosciences, University of Padova, 35131 Padova, Italy
| | - Luca Penasa
- Center of Studies and Activities for Space "G. Colombo," University of Padova, 35131 Padova, Italy
| | - Matteo Massironi
- Department of Geosciences, University of Padova, 35131 Padova, Italy
- Center of Studies and Activities for Space "G. Colombo," University of Padova, 35131 Padova, Italy
| | - Giampiero Naletto
- Department of Physics and Astronomy "Galileo Galilei," University of Padova, 35131 Padova, Italy
- Center of Studies and Activities for Space "G. Colombo," University of Padova, 35131 Padova, Italy
- Consiglio Nazionale delle Ricerche - Istituto di Fotonica e Nanotecnologie Padova, 35131 Padova, Italy
| | - Sabrina Ferrari
- Center of Studies and Activities for Space "G. Colombo," University of Padova, 35131 Padova, Italy
| | - Michele Fondriest
- Department of Geosciences, University of Padova, 35131 Padova, Italy
| | - Dennis Bodewits
- Physics Department, Auburn University, Leach Science Center, Auburn, AL 36849
| | - Carsten Güttler
- Max Planck Institute for Solar System Research, 37077 Göttingen, Germany
| | - Alice Lucchetti
- Istituto Nazionale di Astrofisica, Astronomical Observatory of Padova, 35122 Padova, Italy
| | - Stefano Mottola
- Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt, 12489 Berlin, Germany
| | - Maurizio Pajola
- Istituto Nazionale di Astrofisica, Astronomical Observatory of Padova, 35122 Padova, Italy
| | - Imre Toth
- Research Center for Astronomy and Geosciences, Hungarian Academy of Sciences, Konkoly Observatory, 1525 Budapest, Hungary
| | - Jacob Deller
- Max Planck Institute for Solar System Research, 37077 Göttingen, Germany
| | - Holger Sierks
- Max Planck Institute for Solar System Research, 37077 Göttingen, Germany
| | - Cecilia Tubiana
- Max Planck Institute for Solar System Research, 37077 Göttingen, Germany
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8
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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.
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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
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9
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Grundy WM, Bird MK, Britt DT, Cook JC, Cruikshank DP, Howett CJA, Krijt S, Linscott IR, Olkin CB, Parker AH, Protopapa S, Ruaud M, Umurhan OM, Young LA, Dalle Ore CM, Kavelaars JJ, Keane JT, Pendleton YJ, Porter SB, Scipioni F, Spencer JR, Stern SA, Verbiscer AJ, Weaver HA, Binzel RP, Buie MW, Buratti BJ, Cheng A, Earle AM, Elliott HA, Gabasova L, Gladstone GR, Hill ME, Horanyi M, Jennings DE, Lunsford AW, McComas DJ, McKinnon WB, McNutt RL, Moore JM, Parker JW, Quirico E, Reuter DC, Schenk PM, Schmitt B, Showalter MR, Singer KN, Weigle GE, Zangari AM. Color, composition, and thermal environment of Kuiper Belt object (486958) Arrokoth. Science 2020; 367:science.aay3705. [PMID: 32054693 DOI: 10.1126/science.aay3705] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 01/22/2020] [Indexed: 11/02/2022]
Abstract
The outer Solar System object (486958) Arrokoth (provisional designation 2014 MU69) has been largely undisturbed since its formation. We studied its surface composition using data collected by the New Horizons spacecraft. Methanol ice is present along with organic material, which may have formed through irradiation of simple molecules. Water ice was not detected. This composition indicates hydrogenation of carbon monoxide-rich ice and/or energetic processing of methane condensed on water ice grains in the cold, outer edge of the early Solar System. There are only small regional variations in color and spectra across the surface, which suggests that Arrokoth formed from a homogeneous or well-mixed reservoir of solids. Microwave thermal emission from the winter night side is consistent with a mean brightness temperature of 29 ± 5 kelvin.
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Affiliation(s)
- W M Grundy
- Lowell Observatory, Flagstaff, AZ 86001, USA. .,Department of Astronomy and Planetary Science, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - M K Bird
- Argelander-Institut für Astronomie, University of Bonn, D-53121 Bonn, Germany.,Rheinisches Institut für Umweltforschung, Universität zu Köln, 50931 Cologne, Germany
| | - D T Britt
- University of Central Florida, Orlando, FL 32816, USA
| | - J C Cook
- Pinhead Institute, Telluride, CO 81435, USA
| | | | - C J A Howett
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S Krijt
- Steward Observatory, University of Arizona, Tucson, AZ 85719, USA
| | | | - C B Olkin
- Southwest Research Institute, Boulder, CO 80302, USA
| | - A H Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S Protopapa
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M Ruaud
- NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - O M Umurhan
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,Carl Sagan Center, SETI Institute, Mountain View, CA 94043, USA
| | - L A Young
- Southwest Research Institute, Boulder, CO 80302, USA
| | - C M Dalle Ore
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,Carl Sagan Center, SETI Institute, Mountain View, CA 94043, USA
| | - J J Kavelaars
- National Research Council, Victoria, BC V9E 2E7, Canada.,Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 2Y2, Canada
| | - J T Keane
- California Institute of Technology, Pasadena, CA 91125, USA
| | - Y J Pendleton
- NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - S B Porter
- Southwest Research Institute, Boulder, CO 80302, USA
| | - F Scipioni
- NASA Ames Research Center, Moffett Field, CA 94035, USA.,Carl Sagan Center, SETI Institute, Mountain View, CA 94043, USA
| | - J R Spencer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S A Stern
- Southwest Research Institute, Boulder, CO 80302, USA
| | - A J Verbiscer
- University of Virginia, Charlottesville, VA 22904, USA
| | - H A Weaver
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - R P Binzel
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - M W Buie
- Southwest Research Institute, Boulder, CO 80302, USA
| | - B J Buratti
- NASA Jet Propulsion Laboratory, La Cañada Flintridge, CA 91011, USA
| | - A Cheng
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A M Earle
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - H A Elliott
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - L Gabasova
- Institut de Planétologie et d'Astrophysique de Grenoble, Centre National de la Recherche Scientifique, Université Grenoble Alpes, Grenoble, France
| | - G R Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - M E Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Horanyi
- University of Colorado, Boulder, CO 80309, USA
| | - D E Jennings
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - A W Lunsford
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D J McComas
- Princeton University, Princeton, NJ 08544, USA
| | | | - R L McNutt
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J M Moore
- NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - J W Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - E Quirico
- Institut de Planétologie et d'Astrophysique de Grenoble, Centre National de la Recherche Scientifique, Université Grenoble Alpes, Grenoble, France
| | - D C Reuter
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - P M Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - B Schmitt
- Institut de Planétologie et d'Astrophysique de Grenoble, Centre National de la Recherche Scientifique, Université Grenoble Alpes, Grenoble, France
| | - M R Showalter
- Carl Sagan Center, SETI Institute, Mountain View, CA 94043, USA
| | - K N Singer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - G E Weigle
- Big Head Endian LLC, Leawood, KS 67019, USA
| | - A M Zangari
- Southwest Research Institute, Boulder, CO 80302, USA
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10
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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.
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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
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11
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Combi M, Shou Y, Fougere N, Tenishev V, Altwegg K, Rubin M, Bockelée-Morvan D, Capaccioni F, Cheng YC, Fink U, Gombosi T, Hansen KC, Huang Z, Marshall D, Toth G. The Surface Distributions of the Production of the Major Volatile Species, H 2O, CO 2, CO and O 2, from the Nucleus of Comet 67P/Churyumov-Gerasimenko throughout the Rosetta Mission as Measured by the ROSINA Double Focusing Mass Spectrometer. ICARUS 2020; 335:113421. [PMID: 31631900 PMCID: PMC6800715 DOI: 10.1016/j.icarus.2019.113421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) suite of instruments operated throughout the over two years of the Rosetta mission operations in the vicinity of comet 67P/Churyumov-Gerasimenko. It measured gas densities and composition throughout the comet's atmosphere, or coma. Here we present two-years' worth of measurements of the relative densities of the four major volatile species in the coma of the comet, H2O, CO2, CO and O2, by one of the ROSINA sub-systems called the Double Focusing Mass Spectrometer (DFMS). The absolute total gas densities were provided by the Comet Pressure Sensor (COPS), another ROSINA sub-system. DFMS is a very high mass resolution and high sensitivity mass spectrometer able to resolve at a tiny fraction of an atomic mass unit. We have analyzed the combined DFMS and COPS measurements using an inversion scheme based on spherical harmonics that solves for the distribution of potential surface activity of each species as the comet rotates, changing solar illumination, over short time intervals and as the comet changes distance from the sun and orientation of its spin axis over long time intervals. We also use the surface boundary conditions derived from the inversion scheme to simulate the whole coma with our fully kinetic Direct Simulation Monte Carlo model and calculate the production rates of the four major species throughout the mission. We compare the derived production rates with revised remote sensing observations by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) as well as with published observations from the Microwave Instrument for the Rosetta Orbiter (MIRO). Finally we use the variation of the surface production of the major species to calculate the total mass loss over the mission and, for different estimates of the dust/gas ratio, calculate the variation of surface loss all over the nucleus.
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Affiliation(s)
- Michael Combi
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Yinsi Shou
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicolas Fougere
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Valeriy Tenishev
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Kathrin Altwegg
- Physikalisches Institut, University of Bern, Bern, Switzerland
| | - Martin Rubin
- Physikalisches Institut, University of Bern, Bern, Switzerland
| | - Dominique Bockelée-Morvan
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universites, UPMC Univ. Paris 06, Univ. Paris-Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, F-92195 Meudon, France
| | - Fabrizio Capaccioni
- 4INAF-IAPS, Istituto di Astrofisica e Planetologia Spaziali, via del fosso del Cavaliere 100, I-00133 Rome, Italy
| | - Yu-Chi Cheng
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universites, UPMC Univ. Paris 06, Univ. Paris-Diderot, Sorbonne Paris Cité, 5 place Jules Janssen, F-92195 Meudon, France
| | - Uwe Fink
- Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona, USA
| | - Tamas Gombosi
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Kenneth C Hansen
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Zhenguang Huang
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - David Marshall
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Gabor Toth
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, Michigan, USA
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12
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Combi MR, Mäkinen T, Bertaux JL, Quémerais E, Ferron S, Coronel R. Comet C/2017 S3 (PanSTARRS): Outbursts and Disintegration. THE ASTROPHYSICAL JOURNAL. LETTERS 2019; 884:10.3847/2041-8213/ab4887. [PMID: 31807263 PMCID: PMC6894164 DOI: 10.3847/2041-8213/ab4887] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Solar Wind ANisotropies (SWAN) all-sky hydrogen Lyman-alpha camera on the SOlar and Heliospheric Observer (SOHO) satellite observed the hydrogen coma of comet C/2017 S3 (PanSTARRS) for the last month of its activity from 2018 July 4 to August 4 and what appears to have been its final disintegration just 11 days before its perihelion on August 15. The hydrogen coma indicated water production had a small outburst on July 8 at a heliocentric distance of 1.1AU and then a much larger one on July 20 at 0.8 AU. Over the following two weeks the water production dropped by more than a factor of ten after which it was no longer detectable. The behavior is reminiscent of comet C/1999 S4 (LINEAR) in 2000, which had a few small outbursts on its inbound orbit and a major outburst at a heliocentric distance of about 0.8 AU, which was close to its perihelion, followed by its complete disintegration that was documented by several sets of observations including SWAN. C/2017 S3 (PanSTARRS) however had a much larger water production rate than C/1999 S4 (LINEAR). Here we estimate the size of the nucleus of C/2017 S3 just before its final outburst and apparent disintegration was estimated using the total amount of water produced during its last weeks for a range of values of the refractory/ice ratio in the nucleus. We also determine the size distribution of the disintegrating particles as the comet faded.
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Affiliation(s)
- M R Combi
- Dept. of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143
| | - T Mäkinen
- Finnish Meteorological Institute, Box 503, SF-00101 Helsinki, FINLAND
| | - J-L Bertaux
- LATMOS/IPSL, Université de Versailles Saint-Quentin, 11, Boulevard d'Alembert, 78280, Guyancourt, FRANCE
| | - E Quémerais
- LATMOS/IPSL, Université de Versailles Saint-Quentin, 11, Boulevard d'Alembert, 78280, Guyancourt, FRANCE
| | - S Ferron
- ACRI-st, Sophia-Antipolis, FRANCE
| | - R Coronel
- Dept. of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143
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13
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Stern SA, Weaver HA, Spencer JR, Olkin CB, Gladstone GR, Grundy WM, Moore JM, Cruikshank DP, Elliott HA, McKinnon WB, Parker JW, Verbiscer AJ, Young LA, Aguilar DA, Albers JM, Andert T, Andrews JP, Bagenal F, Banks ME, Bauer BA, Bauman JA, Bechtold KE, Beddingfield CB, Behrooz N, Beisser KB, Benecchi SD, Bernardoni E, Beyer RA, Bhaskaran S, Bierson CJ, Binzel RP, Birath EM, Bird MK, Boone DR, Bowman AF, Bray VJ, Britt DT, Brown LE, Buckley MR, Buie MW, Buratti BJ, Burke LM, Bushman SS, Carcich B, Chaikin AL, Chavez CL, Cheng AF, Colwell EJ, Conard SJ, Conner MP, Conrad CA, Cook JC, Cooper SB, Custodio OS, Dalle Ore CM, Deboy CC, Dharmavaram P, Dhingra RD, Dunn GF, Earle AM, Egan AF, Eisig J, El-Maarry MR, Engelbrecht C, Enke BL, Ercol CJ, Fattig ED, Ferrell CL, Finley TJ, Firer J, Fischetti J, Folkner WM, Fosbury MN, Fountain GH, Freeze JM, Gabasova L, Glaze LS, Green JL, Griffith GA, Guo Y, Hahn M, Hals DW, Hamilton DP, Hamilton SA, Hanley JJ, Harch A, Harmon KA, Hart HM, Hayes J, Hersman CB, Hill ME, Hill TA, Hofgartner JD, Holdridge ME, Horányi M, Hosadurga A, Howard AD, Howett CJA, Jaskulek SE, Jennings DE, Jensen JR, Jones MR, Kang HK, Katz DJ, Kaufmann DE, Kavelaars JJ, Keane JT, Keleher GP, Kinczyk M, Kochte MC, Kollmann P, Krimigis SM, Kruizinga GL, Kusnierkiewicz DY, Lahr MS, Lauer TR, Lawrence GB, Lee JE, Lessac-Chenen EJ, Linscott IR, Lisse CM, Lunsford AW, Mages DM, Mallder VA, Martin NP, May BH, McComas DJ, McNutt RL, Mehoke DS, Mehoke TS, Nelson DS, Nguyen HD, Núñez JI, Ocampo AC, Owen WM, Oxton GK, Parker AH, Pätzold M, Pelgrift JY, Pelletier FJ, Pineau JP, Piquette MR, Porter SB, Protopapa S, Quirico E, Redfern JA, Regiec AL, Reitsema HJ, Reuter DC, Richardson DC, Riedel JE, Ritterbush MA, Robbins SJ, Rodgers DJ, Rogers GD, Rose DM, Rosendall PE, Runyon KD, Ryschkewitsch MG, Saina MM, Salinas MJ, Schenk PM, Scherrer JR, Schlei WR, Schmitt B, Schultz DJ, Schurr DC, Scipioni F, Sepan RL, Shelton RG, Showalter MR, Simon M, Singer KN, Stahlheber EW, Stanbridge DR, Stansberry JA, Steffl AJ, Strobel DF, Stothoff MM, Stryk T, Stuart JR, Summers ME, Tapley MB, Taylor A, Taylor HW, Tedford RM, Throop HB, Turner LS, Umurhan OM, Van Eck J, Velez D, Versteeg MH, Vincent MA, Webbert RW, Weidner SE, Weigle GE, Wendel JR, White OL, Whittenburg KE, Williams BG, Williams KE, Williams SP, Winters HL, Zangari AM, Zurbuchen TH. Initial results from the New Horizons exploration of 2014 MU 69, a small Kuiper Belt object. Science 2019; 364:364/6441/eaaw9771. [PMID: 31097641 DOI: 10.1126/science.aaw9771] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/16/2019] [Indexed: 11/02/2022]
Abstract
The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.
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Affiliation(s)
- S A Stern
- Southwest Research Institute, Boulder, CO 80302, USA.
| | - H A Weaver
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J R Spencer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - C B Olkin
- Southwest Research Institute, Boulder, CO 80302, USA
| | - G R Gladstone
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - W M Grundy
- Lowell Observatory, Flagstaff, AZ 86001, USA
| | - J M Moore
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - D P Cruikshank
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA
| | - H A Elliott
- Southwest Research Institute, San Antonio, TX 78238, USA.,Department of Physics and Astronomy, University of Texas, San Antonio, TX 78249, USA
| | - W B McKinnon
- Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University, St. Louis, MO 63130, USA
| | - J Wm Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - A J Verbiscer
- Department of Astronomy, University of Virginia, Charlottesville, VA 22904, USA
| | - L A Young
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D A Aguilar
- Independent consultant, Carbondale, CO 81623, USA
| | - J M Albers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T Andert
- Universität der Bundeswehr München, Neubiberg 85577, Germany
| | - J P Andrews
- Southwest Research Institute, Boulder, CO 80302, USA
| | - F Bagenal
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - M E Banks
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - B A Bauer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - K E Bechtold
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C B Beddingfield
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - N Behrooz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K B Beisser
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S D Benecchi
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - E Bernardoni
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - R A Beyer
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - S Bhaskaran
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - C J Bierson
- Earth and Planetary Science Department, University of California, Santa Cruz, CA 95064, USA
| | - R P Binzel
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - E M Birath
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M K Bird
- Argelander-Institut für Astronomie, University of Bonn, Bonn D-53121, Germany.,Rheinisches Institut für Umweltforschung, Universität zu Köln, Cologne 50931, Germany
| | - D R Boone
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - A F Bowman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - V J Bray
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA
| | - D T Britt
- Department of Physics, University of Central Florida, Orlando, FL 32816, USA
| | - L E Brown
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M R Buckley
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M W Buie
- Southwest Research Institute, Boulder, CO 80302, USA
| | - B J Buratti
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - L M Burke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S S Bushman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B Carcich
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA.,Cornell University, Ithaca, NY 14853, USA
| | - A L Chaikin
- Independent science writer, Arlington, VT 05250, USA
| | - C L Chavez
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - A F Cheng
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E J Colwell
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S J Conard
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M P Conner
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C A Conrad
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J C Cook
- Pinhead Institute, Telluride, CO 81435, USA
| | - S B Cooper
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - O S Custodio
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C M Dalle Ore
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - C C Deboy
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - P Dharmavaram
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - G F Dunn
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - A M Earle
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - A F Egan
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J Eisig
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M R El-Maarry
- Department of Earth and Planetary Sciences, Birkbeck, University of London, London WC1E 7HX, UK
| | - C Engelbrecht
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B L Enke
- Southwest Research Institute, Boulder, CO 80302, USA
| | - C J Ercol
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - E D Fattig
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - C L Ferrell
- Southwest Research Institute, Boulder, CO 80302, USA
| | - T J Finley
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J Firer
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - W M Folkner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M N Fosbury
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - G H Fountain
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J M Freeze
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - L Gabasova
- University Grenoble Alpes, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, 38000 Grenoble, France
| | - L S Glaze
- NASA Headquarters, Washington, DC 20546, USA
| | - J L Green
- NASA Headquarters, Washington, DC 20546, USA
| | - G A Griffith
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - Y Guo
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Hahn
- Rheinisches Institut für Umweltforschung, Universität zu Köln, Cologne 50931, Germany
| | - D W Hals
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D P Hamilton
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - S A Hamilton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J J Hanley
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - A Harch
- Cornell University, Ithaca, NY 14853, USA
| | - K A Harmon
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - H M Hart
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J Hayes
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - C B Hersman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M E Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T A Hill
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J D Hofgartner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M E Holdridge
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Horányi
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - A Hosadurga
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A D Howard
- Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22904, USA
| | - C J A Howett
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S E Jaskulek
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D E Jennings
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - J R Jensen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M R Jones
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - H K Kang
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D J Katz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D E Kaufmann
- Southwest Research Institute, Boulder, CO 80302, USA
| | - J J Kavelaars
- National Research Council of Canada, Victoria, BC V9E 2E7, Canada
| | - J T Keane
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - G P Keleher
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M Kinczyk
- Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - M C Kochte
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - P Kollmann
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S M Krimigis
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - G L Kruizinga
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - D Y Kusnierkiewicz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M S Lahr
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T R Lauer
- National Optical Astronomy Observatory, Tucson, AZ 26732, USA
| | - G B Lawrence
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J E Lee
- NASA Marshall Space Flight Center, Huntsville, AL 35812, USA
| | | | - I R Linscott
- Independent consultant, Mountain View, CA 94043, USA
| | - C M Lisse
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A W Lunsford
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D M Mages
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - V A Mallder
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - N P Martin
- Independent consultant, Crested Butte, CO 81224, USA
| | - B H May
- Independent collaborator, Windlesham GU20 6YW, UK
| | - D J McComas
- Southwest Research Institute, San Antonio, TX 78238, USA.,Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
| | - R L McNutt
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D S Mehoke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - T S Mehoke
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - H D Nguyen
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - J I Núñez
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A C Ocampo
- NASA Headquarters, Washington, DC 20546, USA
| | - W M Owen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - G K Oxton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A H Parker
- Southwest Research Institute, Boulder, CO 80302, USA
| | - M Pätzold
- Rheinisches Institut für Umweltforschung, Universität zu Köln, Cologne 50931, Germany
| | | | | | - J P Pineau
- Stellar Solutions, Palo Alto, CA 94306, USA
| | - M R Piquette
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA
| | - S B Porter
- Southwest Research Institute, Boulder, CO 80302, USA
| | - S Protopapa
- Southwest Research Institute, Boulder, CO 80302, USA
| | - E Quirico
- University Grenoble Alpes, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, 38000 Grenoble, France
| | - J A Redfern
- Southwest Research Institute, Boulder, CO 80302, USA
| | - A L Regiec
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - D C Reuter
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - D C Richardson
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - J E Riedel
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M A Ritterbush
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - S J Robbins
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D J Rodgers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - G D Rogers
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D M Rose
- Southwest Research Institute, Boulder, CO 80302, USA
| | - P E Rosendall
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K D Runyon
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M G Ryschkewitsch
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - M M Saina
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - P M Schenk
- Lunar and Planetary Institute, Houston, TX 77058, USA
| | - J R Scherrer
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - W R Schlei
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - B Schmitt
- University Grenoble Alpes, Centre National de la Recherche Scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, 38000 Grenoble, France
| | - D J Schultz
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D C Schurr
- NASA Headquarters, Washington, DC 20546, USA
| | - F Scipioni
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - R L Sepan
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - R G Shelton
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - M Simon
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - K N Singer
- Southwest Research Institute, Boulder, CO 80302, USA
| | - E W Stahlheber
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | - J A Stansberry
- Space Telescope Science Institute, Baltimore, MD 21218, USA
| | - A J Steffl
- Southwest Research Institute, Boulder, CO 80302, USA
| | - D F Strobel
- Johns Hopkins University, Baltimore, MD 21218, USA
| | - M M Stothoff
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - T Stryk
- Roane State Community College, Oak Ridge, TN 37830, USA
| | - J R Stuart
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M E Summers
- George Mason University, Fairfax, VA 22030, USA
| | - M B Tapley
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - A Taylor
- KinetX Aerospace, Tempe, AZ 85284, USA
| | - H W Taylor
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - R M Tedford
- Southwest Research Institute, Boulder, CO 80302, USA
| | - H B Throop
- Planetary Science Institute, Tucson, AZ 85719, USA
| | - L S Turner
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - O M Umurhan
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - J Van Eck
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - D Velez
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
| | - M H Versteeg
- Southwest Research Institute, San Antonio, TX 78238, USA
| | - M A Vincent
- Southwest Research Institute, Boulder, CO 80302, USA
| | - R W Webbert
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - S E Weidner
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544, USA
| | - G E Weigle
- Independent consultant, Burden, KS 67019, USA
| | - J R Wendel
- NASA Headquarters, Washington, DC 20546, USA
| | - O L White
- NASA Ames Research Center, Space Science Division, Moffett Field, CA 94035, USA.,SETI Institute, Mountain View, CA 94043, USA
| | - K E Whittenburg
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | | | | | - S P Williams
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - H L Winters
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
| | - A M Zangari
- Southwest Research Institute, Boulder, CO 80302, USA
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Contributions from Accreted Organics to Titan’s Atmosphere: New Insights from Cometary and Chondritic Data. ACTA ACUST UNITED AC 2019. [DOI: 10.3847/1538-4357/aaf561] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Levasseur-Regourd AC, Agarwal J, Cottin H, Engrand C, Flynn G, Fulle M, Gombosi T, Langevin Y, Lasue J, Mannel T, Merouane S, Poch O, Thomas N, Westphal A. Cometary Dust. SPACE SCIENCE REVIEWS 2018; 214:64. [PMID: 35095119 PMCID: PMC8793767 DOI: 10.1007/s11214-018-0496-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 03/16/2018] [Indexed: 05/15/2023]
Abstract
This review presents our understanding of cometary dust at the end of 2017. For decades, insight about the dust ejected by nuclei of comets had stemmed from remote observations from Earth or Earth's orbit, and from flybys, including the samples of dust returned to Earth for laboratory studies by the Stardust return capsule. The long-duration Rosetta mission has recently provided a huge and unique amount of data, obtained using numerous instruments, including innovative dust instruments, over a wide range of distances from the Sun and from the nucleus. The diverse approaches available to study dust in comets, together with the related theoretical and experimental studies, provide evidence of the composition and physical properties of dust particles, e.g., the presence of a large fraction of carbon in macromolecules, and of aggregates on a wide range of scales. The results have opened vivid discussions on the variety of dust-release processes and on the diversity of dust properties in comets, as well as on the formation of cometary dust, and on its presence in the near-Earth interplanetary medium. These discussions stress the significance of future explorations as a way to decipher the formation and evolution of our Solar System.
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Affiliation(s)
- Anny-Chantal Levasseur-Regourd
- Sorbonne Université; UVSQ; CNRS/INSU; Campus Pierre et Marie Curie, BC 102, 4 place Jussieu, F-75005 Paris, France, Tel.: + 33 144274875,
| | - Jessica Agarwal
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg, 3, D-37077, Göttingen, Germany
| | - Hervé Cottin
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Université Paris-Est Créteil et Université Paris Diderot, Institut Pierre Simon Laplace, 94000 Créteil, France
| | - Cécile Engrand
- Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), CNRS/IN2P3 Université Paris Sud - UMR 8609, Université Paris-Saclay, Bâtiment 104, 91405 Orsay Campus, France
| | - George Flynn
- SUNY-Plattsburgh, 101 Broad St, Plattsburgh, NY 12901, United States
| | - Marco Fulle
- INAF - Osservatorio Astronomico, Via Tiepolo 11, 34143 Trieste Italy
| | - Tamas Gombosi
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yves Langevin
- Institut dAstrophysique Spatiale (IAS), CNRS/Université Paris Sud, Bâtiment 121, 91405 Orsay France
| | - Jérémie Lasue
- IRAP, Université de Toulouse, CNRS, UPS, CNES, Toulouse, France
| | - Thurid Mannel
- Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, 8042 Graz, Austria; Physics Institute, University of Graz, Universitätsplatz 5, 8010 Graz, Austria
| | - Sihane Merouane
- Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg, 3, D-37077, Göttingen, Germany
| | - Olivier Poch
- Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
| | - Nicolas Thomas
- Physikalisches Institut, Universität Bern, Sidlerstrasse 5, 3012, Bern, Switzerland
| | - Andrew Westphal
- Space Sciences Laboratory, U.C. Berkeley, Berkeley, California 94720-7450 USA
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16
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O'D Alexander CM, McKeegan KD, Altwegg K. Water Reservoirs in Small Planetary Bodies: Meteorites, Asteroids, and Comets. SPACE SCIENCE REVIEWS 2018; 214:36. [PMID: 30842688 PMCID: PMC6398961 DOI: 10.1007/s11214-018-0474-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 01/11/2018] [Indexed: 06/09/2023]
Abstract
Asteroids and comets are the remnants of the swarm of planetesimals from which the planets ultimately formed, and they retain records of processes that operated prior to and during planet formation. They are also likely the sources of most of the water and other volatiles accreted by Earth. In this review, we discuss the nature and probable origins of asteroids and comets based on data from remote observations, in situ measurements by spacecraft, and laboratory analyses of meteorites derived from asteroids. The asteroidal parent bodies of meteorites formed ≤4 Ma after Solar System formation while there was still a gas disk present. It seems increasingly likely that the parent bodies of meteorites spectroscopically linked with the E-, S-, M- and V-type asteroids formed sunward of Jupiter's orbit, while those associated with C- and, possibly, D-type asteroids formed further out, beyond Jupiter but probably not beyond Saturn's orbit. Comets formed further from the Sun than any of the meteorite parent bodies, and retain much higher abundances of interstellar material. CI and CM group meteorites are probably related to the most common C-type asteroids, and based on isotopic evidence they, rather than comets, are the most likely sources of the H and N accreted by the terrestrial planets. However, comets may have been major sources of the noble gases accreted by Earth and Venus. Possible constraints that these observations can place on models of giant planet formation and migration are explored.
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Affiliation(s)
- Conel M O'D Alexander
- Dept. Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road NW, Washington, DC 20015, USA. . Tel. (202) 478 8478
| | - Kevin D McKeegan
- Department of Earth, Planetary, and Space Sciences, University of California-Los Angeles, Los Angeles, CA 90095-1567, USA.
| | - Kathrin Altwegg
- Physikalisches Institut, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.
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17
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Combi MR, Mäkinen TT, Bertaux JL, Quémerais E, Ferron S, Avery M, Wright C. Water Production Activity of Nine Long-Period Comets from SOHO/SWAN Observations of Hydrogen Lyman-alpha: 2013-2016. ICARUS 2018; 300:33-46. [PMID: 28970625 PMCID: PMC5621766 DOI: 10.1016/j.icarus.2017.08.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Nine recently discovered long-period comets were observed by the Solar Wind Anisotropies (SWAN) Lyman-alpha all-sky camera on board the Solar and Heliosphere Observatory (SOHO) satellite during the period of 2013 to 2016. These were C/2012 K1 (PanSTARRS), C/2013 US10 (Catalina), C/2013 V5 (Oukaimeden), C/2013 R1 (Lovejoy), C/2014 E2 (Jacques), C/2014 Q2 (Lovejoy), C/2015 G2 (MASTER), C/2014 Q1 (PanSTARRS) and C/2013 X1 (PanSTARRS). Of these 9 comets 6 were long-period comets and 3 were possibly dynamically new. Water production rates were calculated from each of the 885 images using our standard time-resolved model that accounts for the whole water photodissociation chain, exothermic velocities and collisional escape of H atoms. For most of these comets there were enough observations over a broad enough range of heliocentric distances to calculate power-law fits to the variation of production rate with heliocentric distances for pre- and post-perihelion portions of the orbits. Comet C/2014 Q1 (PanSTARRS), with a perihelion distance of only ~0.3 AU, showed the most unusual variation of water production rate with heliocentric distance and the resulting active area variation, indicating that when the comet was within 0.7 AU its activity was dominated by the continuous release of icy grains and chunks, greatly increasing the active sublimation area by more than a factor of 10 beyond what it had at larger heliocentric distances. A possible interpretation suggests that a large fraction of the comet's mass was lost during the apparition.
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Affiliation(s)
- M R Combi
- Dept. of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143
| | - T T Mäkinen
- Finnish Meteorological Institute, Box 503, SF-00101 Helsinki, FINLAND
| | - J-L Bertaux
- LATMOS/IPSL, Université de Versailles Saint-Quentin, 11, Boulevard d'Alembert, 78280, Guyancourt, FRANCE
| | - E Quémerais
- LATMOS/IPSL, Université de Versailles Saint-Quentin, 11, Boulevard d'Alembert, 78280, Guyancourt, FRANCE
| | - S Ferron
- ACRI-st, Sophia-Antipolis, FRANCE
| | - M Avery
- Dept. of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143
| | - C Wright
- Dept. of Climate and Space Sciences and Engineering, University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109-2143
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18
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Taylor MGGT, Altobelli N, Buratti BJ, Choukroun M. The Rosetta mission orbiter science overview: the comet phase. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2016.0262. [PMID: 28554981 PMCID: PMC5454230 DOI: 10.1098/rsta.2016.0262] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/07/2017] [Indexed: 05/11/2023]
Abstract
The international Rosetta mission was launched in 2004 and consists of the orbiter spacecraft Rosetta and the lander Philae. The aim of the mission is to map the comet 67P/Churyumov-Gerasimenko by remote sensing, and to examine its environment in situ and its evolution in the inner Solar System. Rosetta was the first spacecraft to rendezvous with and orbit a comet, accompanying it as it passes through the inner Solar System, and to deploy a lander, Philae, and perform in situ science on the comet's surface. The primary goals of the mission were to: characterize the comet's nucleus; examine the chemical, mineralogical and isotopic composition of volatiles and refractories; examine the physical properties and interrelation of volatiles and refractories in a cometary nucleus; study the development of cometary activity and the processes in the surface layer of the nucleus and in the coma; detail the origin of comets, the relationship between cometary and interstellar material and the implications for the origin of the Solar System; and characterize asteroids 2867 Steins and 21 Lutetia. This paper presents a summary of mission operations and science, focusing on the Rosetta orbiter component of the mission during its comet phase, from early 2014 up to September 2016.This article is part of the themed issue 'Cometary science after Rosetta'.
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Affiliation(s)
| | - N Altobelli
- ESA/ESAC, 28692 Villanueva de la Cañada, Spain
| | - B J Buratti
- JPL/California Institute of Technology, Pasadena, CA 91109, USA
| | - M Choukroun
- JPL/California Institute of Technology, Pasadena, CA 91109, USA
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19
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A'Hearn MF. Comets: looking ahead. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:rsta.2016.0261. [PMID: 28554980 PMCID: PMC5454229 DOI: 10.1098/rsta.2016.0261] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/06/2016] [Indexed: 05/25/2023]
Abstract
We outline the key questions about comets that must be answered in order to understand cometary formation in the context of the protoplanetary disc and the role of comets in the formation and evolution of the solar system. We then discuss the new understanding of comets from Rosetta and from other recent advances, including work presented by others at the discussion meeting. Finally, we suggest some key directions for future projects to better address the above questions.This article is part of the themed issue 'Cometary science after Rosetta'.
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Affiliation(s)
- Michael F A'Hearn
- Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA
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20
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21
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El-Maarry MR, Groussin O, Thomas N, Pajola M, Auger AT, Davidsson B, Hu X, Hviid SF, Knollenberg J, Güttler C, Tubiana C, Fornasier S, Feller C, Hasselmann P, Vincent JB, Sierks H, Barbieri C, Lamy P, Rodrigo R, Koschny D, Keller HU, Rickman H, A’Hearn MF, Barucci MA, Bertaux JL, Bertini I, Besse S, Bodewits D, Cremonese G, Da Deppo V, Debei S, De Cecco M, Deller J, Deshapriya JDP, Fulle M, Gutierrez PJ, Hofmann M, Ip WH, Jorda L, Kovacs G, Kramm JR, Kührt E, Küppers M, Lara LM, Lazzarin M, Lin ZY, Lopez Moreno JJ, Marchi S, Marzari F, Mottola S, Naletto G, Oklay N, Pommerol A, Preusker F, Scholten F, Shi X. Surface changes on comet 67P/Churyumov-Gerasimenko suggest a more active past. Science 2017; 355:1392-1395. [DOI: 10.1126/science.aak9384] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 03/06/2017] [Indexed: 11/02/2022]
Affiliation(s)
- M. Ramy El-Maarry
- Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland
- Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80301, USA
| | - O. Groussin
- Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille, UMR 7326, 13388 Marseille, France
| | - N. Thomas
- Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland
| | - M. Pajola
- NASA Ames Research Center, Moffett Field, CA 94035, USA
| | - A.-T. Auger
- Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille, UMR 7326, 13388 Marseille, France
| | - B. Davidsson
- Jet Propulsion Laboratory, Pasadena, CA 91109, USA
| | - X. Hu
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - S. F. Hviid
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - J. Knollenberg
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - C. Güttler
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - C. Tubiana
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - S. Fornasier
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France
| | - C. Feller
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France
| | - P. Hasselmann
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France
| | - J.-B. Vincent
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - H. Sierks
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - C. Barbieri
- Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy
| | - P. Lamy
- Laboratoire d’Astrophysique de Marseille, UMR 7326 CNRS & Université Aix-Marseille, 13388 Marseille Cedex 13, France
| | - R. Rodrigo
- Centro de Astrobiología, Instituto Nacional de Técnica Aeroespacial, 28850 Torrejón de Ardoz, Madrid, Spain
- International Space Science Institute, 3012 Bern, Switzerland
| | - D. Koschny
- Operations Department, European Space Astronomy Centre/ESA, P.O. Box 78, 28691 Villanueva de la Cañada, Madrid, Spain
| | - H. U. Keller
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
- Institut für Geophysik und Extraterrestrische Physik, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - H. Rickman
- Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
- Polish Academy of Sciences, Space Research Center, 00716 Warsaw, Poland
| | - M. F. A’Hearn
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - M. A. Barucci
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France
| | - J.-L. Bertaux
- Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), CNRS–Université de Versailles Saint-Quentin-en-Yvelines–Institut Pierre Simon Laplace, 78280 Guyancourt, France
| | - I. Bertini
- Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy
| | - S. Besse
- Operations Department, European Space Astronomy Centre/ESA, P.O. Box 78, 28691 Villanueva de la Cañada, Madrid, Spain
| | - D. Bodewits
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - G. Cremonese
- Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Padova, 35122 Padova, Italy
| | - V. Da Deppo
- Consiglio Nazionale delle Ricerche–Istituto di Fotonica e Nanotecnologie, Unità Organizzativa di Supporto, Padova Luxor, 35131 Padova, Italy
| | - S. Debei
- Department of Industrial Engineering, University of Padova, 35131 Padova, Italy
| | | | - J. Deller
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - J. D. P. Deshapriya
- LESIA, Observatoire de Paris, PSL Research University, CNRS, Université Paris Diderot, Sorbonne Paris Cité, UPMC Université Paris 06, Sorbonne Universités, Meudon Principal Cedex 92195, France
| | - M. Fulle
- INAF, Osservatorio Astronomico di Trieste, 34014 Trieste, Italy
| | - P. J. Gutierrez
- Instituto de Astrofísica de Andalucía (CSIC), c/ Glorieta de la Astronomía s/n, 18008 Granada, Spain
| | - M. Hofmann
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - W.-H. Ip
- Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan
| | - L. Jorda
- Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille, UMR 7326, 13388 Marseille, France
| | - G. Kovacs
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - J.-R. Kramm
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - E. Kührt
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - M. Küppers
- Operations Department, European Space Astronomy Centre/ESA, P.O. Box 78, 28691 Villanueva de la Cañada, Madrid, Spain
| | - L. M. Lara
- Instituto de Astrofísica de Andalucía (CSIC), c/ Glorieta de la Astronomía s/n, 18008 Granada, Spain
| | - M. Lazzarin
- Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy
| | - Z.-Yi Lin
- Graduate Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan
| | - J. J. Lopez Moreno
- Instituto de Astrofísica de Andalucía (CSIC), c/ Glorieta de la Astronomía s/n, 18008 Granada, Spain
| | - S. Marchi
- Solar System Exploration Research, Virtual Institute, Southwest Research Institute, Boulder, CO 80302, USA
| | - F. Marzari
- Department of Physics and Astronomy, University of Padova, 35122 Padova, Italy
| | - S. Mottola
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - G. Naletto
- Consiglio Nazionale delle Ricerche–Istituto di Fotonica e Nanotecnologie, Unità Organizzativa di Supporto, Padova Luxor, 35131 Padova, Italy
- Department of Information Engineering, University of Padova, 35131 Padova, Italy
- Centro di Ateneo di Studi ed Attivitá Spaziali “Giuseppe Colombo” (CISAS), University of Padova, 35131 Padova, Italy
| | - N. Oklay
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - A. Pommerol
- Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland
| | - F. Preusker
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - F. Scholten
- Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Planetenforschung, 12489 Berlin, Germany
| | - X. Shi
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
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Giant ripples on comet 67P/Churyumov-Gerasimenko sculpted by sunset thermal wind. Proc Natl Acad Sci U S A 2017; 114:2509-2514. [PMID: 28223535 DOI: 10.1073/pnas.1612176114] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Explaining the unexpected presence of dune-like patterns at the surface of the comet 67P/Churyumov-Gerasimenko requires conceptual and quantitative advances in the understanding of surface and outgassing processes. We show here that vapor flow emitted by the comet around its perihelion spreads laterally in a surface layer, due to the strong pressure difference between zones illuminated by sunlight and those in shadow. For such thermal winds to be dense enough to transport grains-10 times greater than previous estimates-outgassing must take place through a surface porous granular layer, and that layer must be composed of grains whose roughness lowers cohesion consistently with contact mechanics. The linear stability analysis of the problem, entirely tested against laboratory experiments, quantitatively predicts the emergence of bedforms in the observed wavelength range and their propagation at the scale of a comet revolution. Although generated by a rarefied atmosphere, they are paradoxically analogous to ripples emerging on granular beds submitted to viscous shear flows. This quantitative agreement shows that our understanding of the coupling between hydrodynamics and sediment transport is able to account for bedform emergence in extreme conditions and provides a reliable tool to predict the erosion and accretion processes controlling the evolution of small solar system bodies.
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