2010/11/22 by Pascal Descamps, P. Descamps, Franck Marchis +29 · 2 citations
Physics and Astronomy · #Astro and Planetary Science #Planetary Science and Exploration #Stellar, planetary, and galactic studies #astro-ph.EP
paper · pdf · doi:10.1016/j.icarus.2010.11.016
35 pages, 3 Tables, 9 Figures. In press to Icarus
openalex publication_date 2010/11/22 · crossref created 2010/11/22 · arxiv created 2010/11/24 · crossref issued 2011/02/01 · crossref published 2011/02/01 · crossref published-print 2011/02/01 · arxiv updated 2015/05/20 · crossref deposited 2018/12/06 · openalex created_date 2025/10/10 · crossref indexed 2026/03/14 · openalex updated_date 2026/07/28
To take full advantage of the September 2008 opposition passage of the M-type asteroid (216) Kleopatra, we have used near-infrared adaptive optics (AO) imaging with the W.M. Keck II telescope to capture unprecedented high resolution images of this unusual asteroid. Our AO observations with the W.M. Keck II telescope, combined with Spitzer/IRS spectroscopic observations and past stellar occultations, confirm the value of its IRAS radiometric radius of 67.5 km as well as its dog-bone shape suggested by earlier radar observations. Our Keck AO observations revealed the presence of two small satellites in orbit about Kleopatra (see Marchis et al., 2008). Accurate measurements of the satellite orbits over a full month enabled us to determine the total mass of the system to be 4.64+/-0.02 1018 Kg. This translates into a bulk density of 3.6 +/-0.4 g/cm3, which implies a macroscopic porosity for Kleopatra of ~ 30-50%, typical of a rubble-pile asteroid. From these physical characteristics we measured its specific angular momentum, very close to that of a spinning equilibrium dumbbell.