Transcript for Out of control Chinese space station expected to fall to Earth within several hours
Now to the out of control space station, plunging from the sky. The Chinese station falling to Earth, expected to burn up within the next several hours. Space agencies are tracking the station and possible debris. Where it hits is anyone's guess. But we are getting a major update tonight. Here's whit Johnson. Reporter: Tonight, the final countdown. The explosive re-entry of China's first space station, expected at any moment. The latest simulation video, showing most of it burning up in the sky. And now, a new prediction. We have extremely high confidence that the united States is in the clear. Reporter: The updated path of re-entry, far south of the United States. The pacific ocean, hundreds of miles off the coast of south America. Still, ever since the Chinese lost control of tiangong one two years ago, the exact location of its fiery finale has been difficult to predict. The aerospace corporation, tracking its orbit, not ruling out another surprise. If it were to re-enter earlier, it would be over Asia. And if it were to re-enter later, it would be south America. And then passing northeast over Africa and into Asia again. Reporter: The odds of getting hit by a piece of space junk are a trillion to one. But that hasn't stopped many from looking to the sky. Including Bill Nye. What's unique about this space station? Debris from outer space, thousands of tons hit the Earth every night, every day, all the time. But this thing is 8 1/2 tons and it's cylindrical. The solar panels are going to go like this or like this, so there are a lot of unknowns. Whit, I see you're not wearing your helmet. A good sign for Americans. If people were in the area around re-entry, what could they see? Reporter: Definitely no helmets needed in North America. Scientists say if you were in South America, you would see a streak of light break apart. Tom?
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