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arXiv · 1410.2033

Comet C/2013 A1 (Siding Spring) as seen with the Herschel Space Observatory

Abstract

The thermal emission of comet C/2013 A1 (Siding Spring) was observed on March 31, 2013, at a heliocentric distance of 6.48 au using the PACS photometer camera of the Herschel Space Observatory. The comet was clearly active, showing a coma that could be traced to a distance of 10", i.e. 50000 km. Analysis of the radial intensity profiles of the coma provided dust mass and dust production rate; the derived grain size distribution characteristics indicate an overabundance of large grains in the thermal emission. We estimate that activity started about 6 months before these observations, at a heliocentric distance of 8 au.

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Cs. Kiss, T. G. Müller, M. Kidger, P. Mattisson, G. Marton. 2014-12-25. Comet C/2013 A1 (Siding Spring) as seen with the Herschel Space Observatory. https://doi.org/10.1051/0004-6361%2F201425127

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