Transcript for NASA Spacecraft Begins 7-Year Journey to Ancient Asteroid
Now to that nasa spacecraft on a seven-year journey to make some big discoveries and ABC's David Kerley has more on this remarkable mission. Good morning, David. Reporter: Good morning, Michael. I'm kind of a space geek. This is an exciting mission. You get to travel to an asteroid and grab some dust that could tell us how all life started on Earth. You may hear more about this asteroid because it's headed our way. It's what we call a global killer. Reporter: Remember Bruce Willis trying to save the Earth from an asteroid in "Armageddon." You don't know how to fail. Press it. Reporter: Well, now nasa is facing a real-life dark and potential asteroid. Its name is bennu. 1600 feet of space rock and there's a chance it could one day hit Earth. It could be catastrophic. I'm not sure it would end all life on Earth but it would be a bad day. Reporter: But that's 150 years off in the mean time -- Liftoff of the osiris-rex. Reporter: Nasa is going for a visit with this probe launching last night to take samples from bennu which may help answer some of the very big questions about the origins of life. I was crying and I said, because we've just done something amazing. Reporter: The probe won't make it to bennu for another two year, won't be back here on Earth until 2023. Now, this probe will never actually land on the asteroid like Bruce Willis did but touch it with its arm and there is a chance that bennu is going to hit us actually in 150 years is 1 in 3,000, which I think those are not really great odds. We should have sent Bruce Willis. We've already seen him do it. Yeah. Why not. All right, thank you, David.
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