A defunct German satellite is expected to fall to Earth this weekend, with experts predicting that up to 30 big pieces of the junked spacecraft could hit the planet. But exactly when and where the satellite will fall remains a mystery.
The 2.7-ton Roentgen Satellite, or ROSAT, will likely plummet to Earth on Saturday or Sunday (Oct. 22 or 23), according to the latest update from the German Aerospace Center.
"Currently, the re-entry date can only be calculated to within plus/minus one day," agency officials said in a statement. "This time slot of uncertainty will be reduced as the date of re-entry approaches. However, even one day before re-entry, the estimate will only be accurate to within plus/minus five hours."
ROSAT weighs about 5,348 pounds (2,426 kilograms) and launched into orbit in June 1990 as part of a joint mission by Germany, the United States and the United Kingdom. In 1998, the satellite's star tracker failed, which caused its X-ray sensors to point directly at the sun. This permanently damaged the spacecraft, and ROSAT was officially decommissioned in February 1999.
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