NASA: Narrows Down UAR Satellite Earth Impact Time

September 22, 2011

NASA: Narrows Down UAR Satellite Earth Impact Time

The U.S. Space Agency is reporting  that the 6.5-ton, city-bus sized, Upper Atmosphere Research Satellite, or UARS is expected to plunge into the lower atmosphere, “sometime during the afternoon of Friday, Sept. 23, Eastern Daylight Time”. While most of the spacecraft will be incinerated, NASA anticipates that 26 potentially hazardous parts, weighing a total of 1100 lbs, could remain intact and hit the Earth.

 The debris will spread along an estimated 500-mile corridor of the Earth’s surface. The strike zone path is somewhere between latitudes 57 deg. N and 57 deg. S of the equator. That’s as far north as Edmonton, Alberta and Aberdeen, Scotland, and as far south as Cape Horn, the tip of South America. Every continent but Antarctica is currently a potential crash site. But since 70% of the Earth’s surface is covered by water, a splash-down for the debris seems more likely. Although, there is always the possibility that some debris could fall on land.

Pinpointing exactly where and when it will strike has been particularly difficult due to  the satellite’s irregular shape and the tumbling action of its orbit.NASA put the odds of anyone being struck by a falling part of the spacecraft at one in 3,200. The individual risk to a particular person is much less – one in 3,200 multiplied by the billions that live under the satellite’s flight path.

The UARS was launched from the space shuttle Discovery in 1991. Its mission was to study the make-up of Earth’s atmosphere, particularly its protective ozone layer. The satellite’s mission was completed in 2005, and NASA decommissioned the craft. The last large U.S.satellite to lose orbit was Skylab it crashed into the Western Australia desert in 1979.

NASA has warned members of the public not to touch any pieces of the spacecraft which may survive the re-entry, urging them to contact local law enforcement authorities.



Publisher: Salient News