Defunct NASA satellite to crash to Earth this week

CAPE CANAVERAL, Florida (Reuters) - A defunct NASA science satellite is expected to fall back to Earth on Friday, showering debris somewhere on the planet although scientists cannot predict exactly where, officials said.

The 6.5-ton Upper Atmosphere Research Satellite, or UARS, was carried into orbit during a space shuttle mission in 1991. It operated for 14 years, collecting measurements of ozone and other chemicals in the atmosphere.

Since completing its mission in 2005, UARS has been slowly losing altitude, tugged by Earth's gravity. On Friday, the 35-foot-long, 15-foot diameter (10.6-metres long, 4.5-metres diameter) satellite is expected to plunge into the atmosphere, NASA reported on its website.