Masses of Nix and Hydra

  title={Masses of Nix and Hydra},
  author={David J. Tholen and Marc W. Buie and William M. Grundy and Garrett T. Elliott},
A four-body orbit solution for the Pluto system yields GM values of 870.3 ± 3.7, 101.4 ± 2.8, 0.039 ± 0.034, and 0.021 ± 0.042 km3 s−2 for Pluto, Charon, Nix, and Hydra, respectively. Assuming a Charon-like density of 1.63 gm cm−3, the implied diameters for Nix and Hydra are 88 and 72 km, leading to visual geometric albedos of 0.08 and 0.18, respectively, though with considerable uncertainty. The eccentricity of Charon’s orbit has a significant nonzero value; however, the 0.030 ± 0.009 deg yr−1… CONTINUE READING