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Optical Spectroscopy of the Large Kuiper Belt Objects 136472 (2005 FY9) and 136108 (2003 EL61)

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 نشر من قبل Stephen Tegler
 تاريخ النشر 2006
  مجال البحث فيزياء
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We present high signal precision optical reflectance spectra of the large Kuiper belt objects 2005 FY9 and 2003 EL61. The spectrum of 2005 FY9 exhibits strong CH4-ice bands. A comparison between the spectrum and a Hapke model indicates the CH4 bands are shifted 3.25 +/- 2.25A relative to pure CH4-ice, suggesting the presence of another ice component on the surface of 2005 FY9, possibly N2-ice, CO-ice, or Ar. The spectrum of 2003 EL61 is remarkably featureless. There is a hint of an O2-ice band at 5773A; however, this feature needs to be confirmed by future spectroscopic observations of 2003 EL61 with a higher continuum signal precision, sufficient to detect a second weaker O2-ice band at 6275A.



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