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SWAS observations of comet 9P/Tempel 1 and Deep Impact

Frank Bensch·Gary J. Melnick·David A. Neufeld·Martin Harwit·Ronald L. Snell·Brian M. Patten
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Abstract

On 4 July 2005 at 1:52 UT the Deep Impact mission successfully completed its goal to hit the nucleus of 9P/Tempel 1 with an impactor, forming a crater on the nucleus and ejecting material into the coma of the comet. The 370 kg impactor collided with the sunlit side of the nucleus with a relative velocity of 10.2 km/s. NASA's Submillimeter Wave Astronomy Satellite (SWAS) observed the 1(10)-1(01) ortho-water ground-state rotational transition in comet 9P/Tempel 1 before, during, and after the impact. No excess emission from the impact was detected by SWAS. However, the water production rate of the comet showed large natural variations of more than a factor of three during the weeks before the impact.

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Frank Bensch, Gary J. Melnick, David A. Neufeld, Martin Harwit, Ronald L. Snell, Brian M. Patten. 2005-10-13. SWAS observations of comet 9P/Tempel 1 and Deep Impact. https://doi.org/10.1017/s1743921306007502

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