Near-Infrared Spectrophotometry of the Satellites and Rings of Uranus
نویسندگان
چکیده
New spectrophotometry from 1.5 to 2.5 /zm is reported for the Uranian satellites Titania, Oberon, and Umbriel. A spectrum of the rings of Uranus from 2.0 to 2.4/zm is also reported. No evidence is found for frost covering the surface of the ring material, consistent with the low albedo of the rings (P~ = 0.03) previously reported by Nicholson and Jones (1980). The surfaces of the satellites are found to be covered by dirty water frost. Assuming albedos of the frost and gray components covering the Uranian satellites to be the same as the light and dark faces of Iapetus, radii are derived that are roughly twice those inferred from the assumption of a visual albedo of 0.5.
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