DAVID GREENE, HOST:
Rachel, I hate to tell you this. The head of NASA is saying that meteors are a real threat to our planet.
RACHEL MARTIN, HOST:
Ah.
GREENE: He warned a room full of scientists about this.
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JIM BRIDENSTINE: This is not about Hollywood. It's not about movies. This is about ultimately protecting the only planet we know right now to host life.
GREENE: That is NASA's administrator, Jim Bridenstine. He was speaking at the Planetary Defense Conference outside Washington, D.C., and he pointed to the Chelyabinsk meteor which injured 1,500 people in Russia back in 2013.
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BRIDENSTINE: So the modeling says this is going to happen once every 60 years. So these events are not rare.
MARTIN: So what do we do about it? Ed Lu is executive director of B612. It's a group that works on planetary defense. And this is what he told NPR's Weekend Edition.
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ED LU: Simply mapping the locations of all the asteroids - where they are, and where they're going. 'Cause that will tell you which, if any, of these things are a danger to the Earth.
GREENE: NASA is working on this. The goal is to track 90 percent of the large objects near Earth. Bridenstine said, so far, the agency is only a third of the way there. Transcript provided by NPR, Copyright NPR.