Extensive water ice within Ceres' aqueously altered regolith: Evidence from nuclear spectroscopy
Abstract
The surface elemental composition of dwarf planet Ceres constrains its regolith ice content, aqueous alteration processes, and interior evolution. Using nuclear spectroscopy data acquired by NASA's Dawn mission, we determined the concentrations of H, Fe, and K on Ceres. The data show that surface materials were processed by the action of water within the interior. The non-icy portion of Ceres' C-bearing regolith contains similar amounts of H to aqueously altered carbonaceous chondrites, but less Fe. This allows for the possibility that Ceres experienced modest ice-rock fractionation, resulting in differences between surface and bulk composition. At mid-to-high latitudes, the regolith contains high concentrations of H, consistent with broad expanses of water ice, confirming theoretical predictions that ice can survive for billions of years just beneath the surface.
Additional Information
© 2016 American Association for the Advancement of Science. 31 July 2016; accepted 23 November 2016. Published online 15 December 2016. Portions of this work were performed by the Planetary Science Institute under contract with the Jet Propulsion Laboratory, California Institute of Technology (JPL); by JPL under contract with NASA; and by the NASA Dawn at Ceres Guest Investigator Program. The Dawn mission is led by the University of California, Los Angeles, and managed by JPL under the auspices of the NASA Discovery Program Office. The Dawn data are archived with the NASA Planetary Data System (http://sbn.psi.edu/pds/archive/dawn.html).Attached Files
Supplemental Material - 14/science.aah6765.DC1/Prettyman.SM.pdf
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Additional details
- Eprint ID
- 72179
- DOI
- 10.1126/science.aah6765
- Resolver ID
- CaltechAUTHORS:20161121-075411945
- NASA/JPL/Caltech
- Created
-
2016-12-16Created from EPrint's datestamp field
- Updated
-
2022-11-23Created from EPrint's last_modified field
- Caltech groups
- Astronomy Department, Division of Geological and Planetary Sciences