DISINTEGRATING ASTEROID P/2013 R3

作者：Jewitt David^*; Agarwal Jessica; Li Jing; Weaver Harold; Mutchler Max; Larson Stephen

来源：Astrophysical Journal Letters, 2014, 784(1): L8.

DOI：10.1088/2041-8205/784/1/L8

• comets: general
• minor planets, asteroids: general
• minor planets, asteroids: individual (P/2013 R3)

Splitting of the nuclei of comets into multiple components has been frequently observed but, to date, no main-belt asteroid has been observed to break up. Using the Hubble Space Telescope, we find that main-belt asteroid P/2013 R3 consists of 10 or more distinct components, the largest up to 200 m in radius (assumed geometric albedo of 0.05) each of which produces a coma and comet-like dust tail. A diffuse debris cloud with total mass similar to 2 x 10(8) kg further envelopes the entire system. The velocity dispersion among the components, Delta V similar to 0.2-0.5 m s(-1), is comparable to the gravitational escape speeds of the largest members, while their extrapolated plane-of-sky motions suggest a break up between 2013 February and September. The broadband optical colors are those of a C-type asteroid. We find no spectral evidence for gaseous emission, placing model-dependent upper limits to the water production rate <= 1 kg s(-1). Breakup may be due to a rotationally induced structural failure of the precursor body.

• 出版日期2014-3-20