One of the most dangerous asteroids on record zipped close by Earth last month. It made headlines on Thursday, when reports said that there's a chance it could strike our planet in less than 20 years. Such a collision could unleash a force as powerful as a couple of thousand atomic bombs. But NASA was quick to calm nerves and point out some very good news. The most dangerous known asteroids don't really pose much of a threat. And there are very few of them. Also, the chances that this one, which the Ukrainian astronomers who discovered it named 2013 TV135, will collide with Earth are extremely slim, NASA said in a statement it called "a reality check."
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In September, a large asteroid passed close by our planet
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The asteroid, 2013 TV135, was discovered this month
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NASA says there is very little chance of it posing a threat to Earth
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Someday a massive asteroid will wreak havoc on Earth, but that is likely millions of years away
That's the size of four football fields, but it does not quite make it an @placeholder crusher.