This web page shows the brightening of Comet 9P/ Tempel 1 during the Deep Impact spacecraft's impact on 2005 July 4 UT. Eventually I'll put a 3-hour movie here.

Light curve for Comet Tempel during impact. The slow brightening trend prior to impact may be due to it's rotation from an end-on orientation toward a more face-on orientation (with a 40-hour rotation period).

My neighbor (Dave Healy), using a 32-inch RC with an eyepiece, reports that the coma brightened, not the nucleus. He estimates 2 or 3 magnitudes of brightening. That makes sense. My CCD images don't have the spatial resolution to distinguish between the two components, so my 36% brightening (0.33 mag) is a lower limit estimate for what happened to the coma.

This site opened:  July 04, 2005.  Last Update:  July 05, 2005