Title: Search for Nitrogen Ice on 2005 FY9, the Brightest Kuiper Belt Object
Abstract: The two minor planets with the greatest absolute magnitudes, 2005 FY9 and 2003 UB313, were discovered this year in our ongoing survey of the outer solar system. The largest, 2003 UB313, is larger than the planet Pluto for all albedo assumptions. Our initial observations of the two minor planets from Keck and Gemini show that they both have large methane ice absorption features. The only other known outer solar system bodies with methane ice are Pluto and Neptune's moon Triton, which both have large amounts of nitrogen ice on their surfaces. Nitrogen ice is very difficult to detect remotely, and thus may be present on 2005 FY9 and 2003 UB313, but would not have been detected in our initial observations. The presence of nitrogen on the surfaces of the bodies is a profound piece of information for understanding the nanobar atmosphere that may be present, as well as the origin of the bodies in the primordial solar system. In 2006A only 2005 FY9 is available for observation, thus we propose to search for nitrogen ice on 2005 FY9 as well as minor species such as carbon monoxide and carbon dioxide using medium resolution NIRI spectroscopy.
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