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arXiv · 1003.5911

Quaoar: A Rock in the Kuiper belt

W. C. Fraser·M. E. Brown
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Abstract

Here we report WFPC2 observations of the Quaoar-Weywot Kuiper belt binary. From these observations we find that Weywot is on an elliptical orbit with eccentricity of 0.14 {\pm} 0.04, period of 12.438 {\pm} 0.005 days, and a semi-major axis of 1.45 {\pm} 0.08 {\times} 104 km. The orbit reveals a surpsingly high Quaoar-Weywot system mass of 1.6{\pm}0.3{\times}10^21 kg. Using the surface properties of the Uranian and Neptunian satellites as a proxy for Quaoar's surface, we reanalyze the size estimate from Brown and Trujillo (2004). We find, from a mean of available published size estimates, a diameter for Quaoar of 890 {\pm} 70 km. We find Quaoar's density to be ρ= 4.2 {\pm} 1.3 g cm^-3, possibly the highest density in the Kuiper belt.

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W. C. Fraser, M. E. Brown. 2010-03-30. Quaoar: A Rock in the Kuiper belt. https://doi.org/10.1088/0004-637x%2F714%2F2%2F1547

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