Scientists will use a radar to study the 2012 DA14 asteroid, as it flies past the Earth tonight, to learn about its structure and composition.
They hope to use the information to help them plan in the event of another incoming space rock.
Video source: NASA
Scientists are looking at ways to 'nudge' an asteroid if it was a threat to Earth, as blowing it up would only result in debris falling to Earth, they said.
Tonight an asteroid will approach Earth, passing closer than ever before.
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