Paper: astro-ph/0507036
Date: Fri, 1 Jul 2005 19:35:09 GMT (405kb)

Title: Thermal evolution and activity of Comet 9P/Tempel 1 and simulation of a
deep impact

Authors: G.Sarid (1), D. Prialnik (1), K. J. Meech (2), J. Pittichova (2) and
T. L. Farnham (3) ((1) Department of Geophysics and Planetary Sciences, Tel
Aviv University, (2) Institute for Astronomy, University of Hawaii, (3)
Department of Astronomy, University of Maryland)
Comments: 25 pages, 8 figures, accepted for publication in PASP (in press). For
fig.xx (composite image, sec.4) and a better resolution of fig.6 see,
http://geophysics.tau.ac.il/personal/gal%5Fsarid/
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We use a quasi 3-D thermal evolution model for a spherical comet nucleus,
which takes into account the diurnal and latitudinal variation of the solar
flux, but neglects lateral heat conduction. We model the thermal evolution and
activity of Comet 9P/Tempel 1, in anticipation of the Deep Impact mission
encounter with the comet. We also investigate the possible outcome of a
projectile impact, assuming that all the energy is absorbed as thermal energy.
An interesting result of this investigation, is that the estimated amount of
dust ejected due to the impact is equivalent to 2--2.6 days of activity, during
"quiet" conditions, at perihelion.

We show that production rates of volatiles that are released in the interior
of the nucleus depend strongly on the porous structure, in particular on the
surface to volume ratio of the pores. We develop a more accurate model for
calculating this parameter, based on a distribution of pore sizes, rather than
a single, average pore size.

\\ ( http://arXiv.org/abs/astro-ph/0507036 , 405kb)