Transcript for Stargazers Watch Earthbound Satellite Make Fiery Reentry
There is a space mystery playing out tonight. It could happen at any moment, anywhere. A satellite falling from the sky. No one is sure where the pieces will land. The experts say likely in the ocean. Fwhau meet but that meteorite is fresh in all of our minds from last year. And here tonight, abc's clayton sandell. Reporter: It's a galactic heads up. In just hours, a research satellite will crash, or splash, down to earth. We cannot say where re-entry is going to happen. Reporter: Goch launched in 2009, studying earth's gravity field. But now it's out of gas. Just another piece of spiraling space junk. Nasa estimates we are surrounded by 20,000 pieces, zipping lialong at 25,000 miles an hour. Causing disaster for astronauts when russians blow up a satellite in the movie "gravity." But in real life, when it falls to earth, most of it is harmless. About 15,000 tons have returned from space. Most of this burns up when it re-enters. Reporter: But experts say pieces as big as 200 pounds could reach the ground. Give or take a few pounds, that's a piece roughly my size. In february, cameras captured a 10,000-ton meteor exploding over russia. Injuring hundreds. But scientists say you're far more likely to win the lottery than have the sky fall on your head. Back in 1997, lottie williams of tulsa became the only person ever known to get hit. Just a brush, really. Sometimes the best advice the simplest. My advice is to be outside. If you see it coming, run. Uh-huh. Reporter: Like that apple that first sparked sir isaac newton's theory of gravity 300 years ago, the satellite is once again proving that everything that goes up, must come down. Clayton sandell, abc news, denver.
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