MOUNTAIN VIEW (CBS SF) – A dead 6-ton satellite baffled NASA experts Friday by slowing its descent toward Earth and delaying its ultimate crash until the weekend.

Scientists were unable to pinpoint the exact time and place where the Upper Atmosphere Research Satellite, or UARS, will land due to unpredictable changes in the thickness of the atmosphere, fuelled in part by a powerful solar flare on Thursday.

But when it does make landfall, chances are the debris will not hit anyone in the Bay Area or elsewhere in North America.

The odds of getting hit by space junk are slim to none, officials said. They noted that there is only one recorded incident of a person getting hit by falling debris and it happened in 1997 in Tulsa, Oklahoma.

You can bet that scientists at the NASA Ames Research Center in Mountain View are keeping a close eye on the situation.

As CBS 5 first reported in May, researchers there spent the past two years studying ways to use lasers to battle space junk, which has become an increasing threat.

The satellite expected to crash this weekend is one of about 20,000 pieces of space debris loitering in orbit around Earth.

Scientist Creon Levit at NASA Ames said most of the threatening space junk is from space launches of satellites and other objects years ago when no one was concerned about debris control.

“Nowadays when you launch something into space,” said Levit, “you have to have a debris mitigation plan.”

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