It wasn’t always junk. The latest doomed craft, called ROSAT, is a German space telescope that observed in X-ray light from 1990 to 1999 in an orbit 575 km above the Earth.
Atmospheric drag has already brought ROSAT (ROentgen SATellite) to a height of less than 327 km and it has no on-board propulsion system to control its descent.
NASA experts are warning that as many as 30 fragments, weighing a total of 1.6 tons, could survive re-entry to hit the ground, including the largest chunk, the observatory’s hefty glass mirror.
It will re-enter the atmosphere at a speed of around 28,000 km per hour and disintegrate in early November. There is currently an error of plus or minus five weeks in this prediction, so the crash landing could occur in early October.
Fluctuations in solar activity which can cause variation in the density of the fringes of the atmosphere add to the uncertainty.
Most of the inhabited world lies under the track of ROSAT which flies in an orbit that carries it from 53 degrees north to 53 degrees south. Experts expect most of the debris to impact the ground in a compact region but fragments could fall within an 80 km wide path.
EURS and FEMA
With UARS, a massive dead satellite due to plunge back to Earth this week, the Federal Emergency Management Agency (FEMA) is laying the groundwork for a fast response in case the 6 1/2-ton spacecraft falls over, or on American soil.
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