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arXiv · 1104.4906

Water Production by Comet 103P/Hartley 2 Observed with the SWAN Instrument on the SOHO Spacecraft

M. R. Combi·J. -L. Bertaux·E. Quémerais·S. Ferron·J. T. T. Mäkinen
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Abstract

Global water production rates were determined from the Lyman-α emission of hydrogen around comet 103P/Hartley 2, observed with the SWAN (Solar Wind ANisotropies) all-sky camera on the SOHO spacecraft from September 14 through December 12, 2010. This time period included the November 4 flyby by the EPOXI spacecraft. Water production was 3 times lower than during the 1997 apparition also measured by SWAN. In 2010 it increased by a factor of ~2.5 within one day on September 30 with a similar corresponding drop between November 24 and 30. The total surface area of sublimating water within {\pm}20 days of perihelion was ~0.5 km^2, about half of the mean cross section of the nucleus. Outside this period it was ~0.2 km^2. The peak value was 90%, implying a significant water production by released nucleus icy fragments.

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M. R. Combi, J. -L. Bertaux, E. Quémerais, S. Ferron, J. T. T. Mäkinen. 2011-04-26. Water Production by Comet 103P/Hartley 2 Observed with the SWAN Instrument on the SOHO Spacecraft. https://doi.org/10.1088/2041-8205%2F734%2F1%2Fl6

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