Plummeting US Satellite to Hit Earth Friday
September 20, 2011
This conceptual image shows the Upper Atmosphere Research Satellite, launched on September 15, 1991, by the space shuttle Discovery.
20 years ago this month, NASA launched the Upper Atmosphere Research Satellite (UARS). And now that bus-sized satellite is plunging toward Earth.
Mark Matney, an orbital debris scientist at NASA's Johnson Space Center in Texas, says UARS will likely reenter the atmosphere on September 23, 2011. He says scientists will be able to narrow the time frame as it gets closer.
As far as where it will crash, Matney says UARS passes over the Earth between 57 degrees north latitude and 57 degrees south latitude.
"Everything from Canada down to the tip of South America, and from Siberia down to the tip of Africa and Australia [could be where the satellite lands]," says Matney. "So, it's quite a bit of land."
It is also quite a bit of ocean. Given that more than two-thirds of the planet is covered by water, space debris usually lands with a splash.
Still, there is the chance that UARS could land with a thud, although NASA's Matney says this week's satellite reentry is not cause for great concern.
Take Cover?
"If you talk about the probability of you getting hit, it's something like one in trillions, so actually the odds of you getting hit is quite small," Matney says. "So, I don't think anybody needs to be unduly concerned about it."
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