Detection of Water Ice on the Centaur 1997 CU_(26)
We report the detection of the 1.5 and 2.0 μm absorption bands due to water ice in the near-infrared reflection spectrum of the Centaur 1997 CU_(26), which is currently located just outside the heliocentric distance of Saturn. The water ice bands are weaker than those detected on the surface of any other solar system body; the spectrum is well fit with a model surface consisting predominantly of a neutral dark absorbing substance with only ~3% areal coverage of water ice. The spectrum thus appears very different from that of the Centaur 5140 Pholus, although both objects are of similar brightness and are at similar heliocentric distances.
Additional Information© 1998 American Astronomical Society. Received 1998 May 5; accepted 1998 July 2; published 1998 August 24. Data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the Universities of California, and the National Aeronautics and Space Administration. The observatory was made possible by the generous financial support of the W. M. Keck Foundation. We thank the referee for useful and informative comments.
Published - 1538-4357_505_1_L65.pdf