Satellite L-21 (UARS) entered our atmosphere with ease, giving a breath of fresh air to skywatchers everywhere. Only moments after the excitement, we come to find that yet another satellite is to fall to Earth. The satellite named ROSAT was launched by NASA on June 1, 1990, set for a mission to last five years, instead lasting eight years then shutting down February 12, 1999.
The X-ray observatory satellite is expected to fall between the end of October and December, 2011. The satellite began as a cooperative program between Germany, the United Stated and the United Kingdom. The name ROSAT came from a short form of the original name Roentgen Satellite. Although being smaller than L-21, it is predicted to be more of a risk of injury upon impact. The German Space Agency predicts approximately 30 pieces of the 5,300-pound spacecraft to survive through re-entry.
ROSAT was designed and built in Germany using a great amount of ceramics and glass, materials that are unlikely to disintegrate through the immense heat of re-entry. The estimated odds of injury is said to be 1 in 2,000 people, opposed to the estimated 1 in 3,200 odds from the L-21. To date, no one has been struck by falling space debris.
Unfortunately, it is difficult for the German Space Agency to predict where the satellite will strike. When an object plummets to Earth, the density in the atmosphere is so big, so far up, that it produces different amounts of drag. This means that a crash site prediction that was wrong by merely a few minutes could be hundreds of miles away from the actual site. L-21 landed over a 500-mile span in the Pacific Ocean by Christmas Island avoiding any injuries. A YouTube video posted from Italy claims to have witnessed debris from the L-21 satellite falling to Earth. It is hard to determine whether it is a shooting star or actually debris from the satellite, although beautiful either way. Keep a lookout in the next couple months and you may be able to catch a once-in-a-lifetime sighting of a falling satellite.