Satellite tumbling toward Earth causes concern at NASA

Since we were kids we've been told it's impossible to count the number of stars in space.

It is though, apparently, a bit easier to figure out the amount of junk floating amongst them.

NASA calculates as many as 22,000 pieces of debris are orbiting the earth right now.

But the scientists and the rest of the world are worried about one, the nearly six-ton upper atmosphere research satellite that is plummeting back to earth.

NASA still isn't sure when and where it might hit.

Right now their best guess is Friday, somewhere between Newfoundland and Argentina.

"It's difficult to be precise when the object is not behaving. It's tumbling in ways that we can't control," says NASA orbital debris scientist Dr. Mark Matney.

Most of the satellite should disintegrate during re-entry, but 26 pieces or so will make it all the way to earth.

Some of those could be significant in size and weight.

So you're wondering, no doubt, what are the odds?

With about three-quarters of the earth covered by water, nasa puts the chances at one in 3,200 that someone, somewhere will be hit.

With around seven billion of us on the planet, the odds that you'll be hit are 1 in 21-trillion.

In fact there's a much better chance you'll get struck by lightning this year.

Those odds are one in a million.

One thing scientists are almost 100-percent sure of is that at least three more satellites will make uncontrolled entries into our atmosphere.

The next free fall is expected in April of 2014.

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