2011/09/15 by Henry H. Hsieh, Bin Yang, Nader Haghighipour
Physics and Astronomy · #Astro and Planetary Science #Planetary Science and Exploration #Stellar, planetary, and galactic studies #astro-ph.EP
paper · pdf · doi:10.1088/0004-637x/744/1/9
13 pages, 4 figures, accepted for publication in ApJ
arxiv created 2011/09/15 · openalex publication_date 2011/12/07 · arxiv updated 2015/05/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We present observations and a dynamical analysis of the comet-like main-belt object, (596) Scheila. V -band photometry obtained on UT 2010 December 12 indicates that Scheila's dust cloud has a scattering cross-section ∼1.4 times larger than that of the nucleus, corresponding to a dust mass of M d ∼ 3 × 10 7 kg. V − R color measurements indicate that both the nucleus and dust are redder than the Sun, with no significant color differences between the dust cloud's northern and southern plumes. We also undertake an ultimately unsuccessful search for CN emission, where we find CN and H 2 O production rates of Q CN < 9 × 10 23 s −1 and s −1 . Numerical simulations indicate that Scheila is dynamically stable for >100 Myr, suggesting that it is likely native to its current location. We also find that it does not belong to a dynamical asteroid family of any significance. We consider sublimation-driven scenarios that could produce the appearance of multiple plumes of dust emission, but reject them as being physically implausible. Instead, we concur with previous studies that the unusual morphology of Scheila's dust cloud is most simply explained by a single oblique impact, meaning that this object is likely not a main-belt comet but is instead the second disrupted asteroid after P/2010 A2 (LINEAR) to be discovered.