Sometime between today and Saturday, there is a 1 in 3,200 chance of a person being hit by a falling satellite.  The Upper Atmosphere Research Satellite (UARS) was decommissioned in December 2005, and its altitude has been slowly decreasing ever since.

The 12,500 pound UARS, the size of a school bus, is traveling at 17,000 miles per hour as it approaches reentry.  As it breaks up, the debris will be spread along a path as long as 500-miles.

Get more details on the falling UARS satellite here, and track it's location here.