PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b
GJ 1132b is a nearby Earth-sized exoplanet transiting an M dwarf, and is among the most highly characterizable small exoplanets currently known. In this paper, we study the interaction of a magma ocean with a water-rich atmosphere on GJ 1132b and determine that it must have begun with more than 5 wt...
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| Format: | Article |
| Language: | en_US |
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IOP Publishing
2017
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| Online Access: | http://hdl.handle.net/1721.1/108568 |
| _version_ | 1826189526317400064 |
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| author | Schaefer, Laura Wordsworth, Robin D. Sasselov, Dimitar Berta-Thompson, Zachory K |
| author2 | MIT Kavli Institute for Astrophysics and Space Research |
| author_facet | MIT Kavli Institute for Astrophysics and Space Research Schaefer, Laura Wordsworth, Robin D. Sasselov, Dimitar Berta-Thompson, Zachory K |
| author_sort | Schaefer, Laura |
| collection | MIT |
| description | GJ 1132b is a nearby Earth-sized exoplanet transiting an M dwarf, and is among the most highly characterizable small exoplanets currently known. In this paper, we study the interaction of a magma ocean with a water-rich atmosphere on GJ 1132b and determine that it must have begun with more than 5 wt% initial water in order to still retain a water-based atmosphere. We also determine the amount of O[subscript 2] that can build up in the atmosphere as a result of hydrogen dissociation and loss. We find that the magma ocean absorbs at most ~10% of the O[subscript 2] produced, whereas more than 90% is lost to space through hydrodynamic drag. The most common outcome for GJ 1132b from our simulations is a tenuous atmosphere dominated by O[subscript 2], though, for very large initial water abundances, atmospheres with several thousands of bars of O[subscript 2] are possible. A substantial steam envelope would indicate either the existence of an earlier H[subscript 2] envelope or low XUV flux over the system's lifetime. A steam atmosphere would also imply the continued existence of a magma ocean on GJ 1132b. Further modeling is needed to study the evolution of CO[subscript 2] or N[subscript 2]-rich atmospheres on GJ 1132b. |
| first_indexed | 2024-09-23T08:16:14Z |
| format | Article |
| id | mit-1721.1/108568 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T08:16:14Z |
| publishDate | 2017 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | mit-1721.1/1085682024-06-27T14:10:45Z PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b Schaefer, Laura Wordsworth, Robin D. Sasselov, Dimitar Berta-Thompson, Zachory K MIT Kavli Institute for Astrophysics and Space Research Berta-Thompson, Zachory K GJ 1132b is a nearby Earth-sized exoplanet transiting an M dwarf, and is among the most highly characterizable small exoplanets currently known. In this paper, we study the interaction of a magma ocean with a water-rich atmosphere on GJ 1132b and determine that it must have begun with more than 5 wt% initial water in order to still retain a water-based atmosphere. We also determine the amount of O[subscript 2] that can build up in the atmosphere as a result of hydrogen dissociation and loss. We find that the magma ocean absorbs at most ~10% of the O[subscript 2] produced, whereas more than 90% is lost to space through hydrodynamic drag. The most common outcome for GJ 1132b from our simulations is a tenuous atmosphere dominated by O[subscript 2], though, for very large initial water abundances, atmospheres with several thousands of bars of O[subscript 2] are possible. A substantial steam envelope would indicate either the existence of an earlier H[subscript 2] envelope or low XUV flux over the system's lifetime. A steam atmosphere would also imply the continued existence of a magma ocean on GJ 1132b. Further modeling is needed to study the evolution of CO[subscript 2] or N[subscript 2]-rich atmospheres on GJ 1132b. MIT Torres Fellowship for Exoplanet Research 2017-05-02T13:59:33Z 2017-05-02T13:59:33Z 2016-09 Article http://purl.org/eprint/type/JournalArticle 1538-4357 http://hdl.handle.net/1721.1/108568 Schaefer, Laura et al. “PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b.” The Astrophysical Journal 829.2 (2016): 63. © 2016 The American Astronomical Society en_US http://dx.doi.org/10.3847/0004-637x/829/2/63 Astrophysical Journal Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf IOP Publishing American Astronomical Society |
| spellingShingle | Schaefer, Laura Wordsworth, Robin D. Sasselov, Dimitar Berta-Thompson, Zachory K PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b |
| title | PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b |
| title_full | PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b |
| title_fullStr | PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b |
| title_full_unstemmed | PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b |
| title_short | PREDICTIONS OF THE ATMOSPHERIC COMPOSITION OF GJ 1132b |
| title_sort | predictions of the atmospheric composition of gj 1132b |
| url | http://hdl.handle.net/1721.1/108568 |
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