Surface characterization of 28978 Ixion (2001 KX76)
Abstract
The Plutino 28978 Ixion, one of the largest objects in the Kuiper Belt, is measured by R filter photometry and linear polarimetry over the phase angle range as well as by BVRI colours and visible spectroscopy. Ixion is a medium red object with spectral slope of 17.7%/100 nm (400-900 nm). While its opposition phase curve surge (0.2 mag/deg) is within the typical range found for other solar system objects, it displays unusually high negative polarization (min. -1.3%). Comparison with model spectra and numerical modeling of the opposition brightening and polarization effects suggest an areal mixture of absorbing (dark) and icy (bright) compounds on its surface: the mixing ratio is about 6:1 for dark and bright material of 0.21 and 0.79 single-scattering albedo and of 250 and 33 dimensionless mean free path (length multiplied by wave number), respectively.
Based on observations collected at the ESO VLT within programs 69.C-0133 and 167.C-0340.- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- February 2004
- DOI:
- 10.1051/0004-6361:20040005
- Bibcode:
- 2004A&A...415L..21B
- Keywords:
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- transneptunian object;
- 28978 Ixion: 2001 KX$_{76