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arXiv · 0711.4974

Polarimetry of the dwarf planet (136199) Eris

I. Belskaya·S. Bagnulo·K. Muinonen·M. A. Barucci·G. P. Tozzi·S. Fornasier·L. Kolokolova
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Abstract

We investigate the surface characteristics of the large dwarf planet (136199) Eris. With the FORS1 instrument of the ESO VLT, we have obtained Bessell broadband R linear polarimetry and broadband V and I photometry. We have modelled the observations in terms of the coherent-backscattering mechanism to constrain the surface properties of the object. Polarimetric observations of Eris show a small negative linear polarization without opposition surge in the phase angle range of 0.15-0.5 degrees. The photometric data allow us to suppose a brightness opposition peak at phase angles below 0.2-0.3 degrees. The data obtained suggest possible similarity to the polarimetric and photometric phase curves of Pluto. The measured absolute magnitude and broadband colors of Eris are H_V=-1.15, V-R=0.41, and V-I=0.75.

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I. Belskaya, S. Bagnulo, K. Muinonen, M. A. Barucci, G. P. Tozzi, S. Fornasier, L. Kolokolova. 2007-11-30. Polarimetry of the dwarf planet (136199) Eris. https://doi.org/10.1051/0004-6361:20078241

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