Elsevier

Icarus

Volume 185, Issue 2, December 2006, Pages 563-567
Icarus

Note
The surface composition of Ceres: Discovery of carbonates and iron-rich clays

https://doi.org/10.1016/j.icarus.2006.08.022Get rights and content

Abstract

We present observational evidence that carbonates and iron-rich clays are present on the surface of Ceres. These components are also present in CI chondrites and provide a means of explaining the unusual spectrum of this object as well as providing potential insight into its evolution.

Section snippets

Conclusions

New observations of Ceres in the 2–4 μm spectral region were obtained in May 2005 using SpeX on the IRTF. Analysis of thermally-corrected spectra indicates the presence of carbonates at an abundance of 4–6% on Ceres' surface, similar to what is seen in CI meteorites. These carbonates are responsible for bands in the 3.3 and 3.8–3.9 μm region. Iron-rich phyllosilicates or ammonium-bearing phyllosilicates can both account for an absorption band at 3.05 μm, but consideration of mid-IR data from

Acknowledgements

This work was supported by a grant from the NASA Planetary Astronomy program. Thanks to the native peoples of Hawaii for allowing their sacred mountain to be used for astronomical research. Thoughtful reviews by Tom McCord and Larry Lebofsky greatly improved this manuscript. This research has made use of NASA's Astrophysics Data System.

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    1

    Visiting Astronomer at the Infrared Telescope Facility, which is operated by the University of Hawaii under Cooperative Agreement No. NCC 5-538 with the National Aeronautics and Space Administration, Science Mission Directorate, Planetary Astronomy Program.

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