Peculiar Near-Nucleus Outgassing of Comet 17P/Holmes During Its 2007 Outburst
نویسندگان
چکیده
We present high angular resolution Submillimeter Array observations of the outbursting Jupiter family comet 17P/Holmes on 2007 October 26–29, achieving a spatial resolution of 2.5, or∼3000 km at the comet distance. The observations resulted in detections of the rotational lines CO 3–2, HCN 4–3, HCN 4–3, CS 7–6, H2CO 31,2-21,1, H2S 22,0–21,1, and multiple CH3OH lines, along with the associated dust continuum at 221 and 349 GHz. The continuum has a spectral index of 2.7±0.3, slightly steeper than blackbody emission from large dust particles. From the imaging data, we identify two components in the molecular emission. One component is characterized by a relatively broad line width (∼1 km s FWHM) exhibiting a symmetric outgassing pattern with respect to the
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