QUESTION:
Is there any residual heat signatures detectable by Galileo from
the sl9 comet impact? If not, when did the "fires" finally die away?

ANSWER from Chris Tanski on March 3, 1997:
The fireballs died down approximately ten minutes after they formed
according to observations by ground and space-based telescopes. About
30 minutes after the fireballs were formed, they turned into big
dark clouds, "dark spots" and were easily visibles with ground-based
telescopes. The major structures were still visible several months
later.