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arXiv · 1104.4672

Rotation of Comet Hartley 2 from Structures in the Coma

Nalin H. Samarasinha·Beatrice E. A. Mueller·Michael F. A'Hearn·Tony L. Farnham·Alan Gersch
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Abstract

The CN coma structure of the EPOXI mission target, comet 103P/Hartley 2, was observed during twenty nights from September to December 2010. These CN images probe the rotational state of the comet's nucleus and provide a ground-based observational context to complement the EPOXI observations. A dynamically excited cometary nucleus with a changing rotational rate is observed, a characteristic not seen in any comet in the past. The lack of rotational damping during the four-month observing interval places constraints on the interior structure of the nucleus.

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Nalin H. Samarasinha, Beatrice E. A. Mueller, Michael F. A'Hearn, Tony L. Farnham, Alan Gersch. 2011-04-25. Rotation of Comet Hartley 2 from Structures in the Coma. https://doi.org/10.1088/2041-8205%2F734%2F1%2Fl3

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