October 18, 2011
ROSAT Satellite Could Plunge To Earth By Halloween
Less than a month after one defunct satellite plummeted back to Earth, it appears as though a second is on its way, and the debris could reach our planet's surface by the end of the month, according to a Monday report by Dan Vergano of USA Today.
Sometime between 11:23 p.m. EDT on September 23 and 1:09 a.m. EDT on September 24, the Upper Atmosphere Research Satellite (UARS) fell back to earth, splashing down somewhere in the Pacific Ocean.
Now Vergano, channeling baseball great Yogi Berra, said it was "dÃ©jÃ vu all over again," as a second satellite -- the German-built RÃ¶ntgensatellit or ROSAT -- will likely enter the planet's atmosphere sometime prior to November.
As previously reported here on RedOrbit, the ROSAT is a 2.4 ton space telescope, built by the German Aerospace Center (DLR) and disabled after a guidance system failure in 1999. Originally, experts believed that the satellite would burn up completely in the Earth's atmosphere.
It appears as though that will no longer be the case, however, as pieces of debris from the X-ray telescope, some of which reportedly could weigh up to 800 pounds, might collide with the planet's surface shortly after ROSAT's re-entry, which Vergano reports could happen around Halloween.
"It will not be possible to make any kind of reliable forecast about where the satellite will actually come down until about one or two hours before the fact," Heiner Klinkrad of the European Space Agency (ESA) said in a statement, according to USA Today.
"In the final phase, ROSAT will be 'caught' by the atmosphere at which point it will not even complete an orbit around the Earth: Instead, it will go into 'free fall'," Klinkrad added.
According to Vergano, the DLR has said that the odds of anyone being hit by falling fragments of the satellite are 1 in 2,000. For the record, NASA had placed the odds of anyone being hit by UARS debris at 1 in 3,500, making it somewhat more likely that ROSAT could cause physical harm.
ROSAT is a 5,300-pound satellite that was launched in 1990. The satellite, named after Wilhelm Roentgen, the Nobel Prize winning physicist who discovered X-rays, embarked on an 18-month mission to map interstellar sources of X-rays.
"ROSAT mapped roughly 110,000 stars, supernovas and cosmic ray sources of X-rays," Vergano said. "It also discovered that comets emit X-rays and went silent in 1999, years after the extension of its original mission."
Telegraph reporter Andy Bloxham reported on the German satellite's impending descent and the possibility of debris surviving re-entry back in September. He noted at that time that as many as 30 pieces of metal and carbon fiber, including ROSAT's giant, heat-resistant mirrors, were "expected to survive the blazing temperatures of re-entry to the Earth´s atmosphere and strike land."
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