According to Russian media, preliminary data from US STRATCOM’s Joint Space Operation’s Center predicts that debris from Phobos-Grunt could impact southwestern Afghanistan in the Helmand province on January 14, 2012. The prediction, which was derived from current orbital data, was provided by US STRATCOM to the Russian Federal Space Agency under its Space Situational Sharing (SSA) Program. The preliminary calculation provided by US STRATCOM is a refined calculation from a previous prediction that Phobos-Grunt will fall from orbit between January 9 and 19, 2012 in the range of 51.4 degrees north latitude to 51.4 degrees south latitude. This zone includes the continental Unites States, China, Africa, Australia, Japan, the southern part of Western Europe and Ukraine. The prior prediction does not include Belarus and much of the territory of Russia, including Moscow.
According to the Russian Federal Space Agency, about 20-30 fragments of refractory materials of the total weight not exceeding 200 kilogram could reach the surface of the Earth. This is in contradiction to earlier statements by the Agency that no components of the spacecraft would survive reentry. However, the Agency continues to insist that the propellant on the spacecraft will not survive reentry since the propellant tanks are made of aluminum and expected to melt from the heat of reentry thereby allowing the propellant to explode in the upper atmosphere. This assertion is supported by Nicholas Johnson, NASA’s chief space debris scientist.
The announced predicted reentry and impact site of Phobos-Grunt is likely to change as its orbit continues to decay. Current models of reentering space objects only allow accurate predictions a few hours before the actual event as was seen with the reentries of NASA’s UARS and DLR’s ROSAT spacecraft in 2011. Debris from the respective spacecraft was expected to survive reentry and calculations have determined that any surviving debris fell into the Pacific Ocean and the Bay of Bengal.
Source: Ria Novosti
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