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Tracking Apophis

August 12, 2021

Earth has dodged a cosmic bullet — at least for now. Tracking with a radio telescope early this year showed there’s no chance the asteroid Apophis will hit us any time in the next century. Until those observations, there was a tiny chance it might slam into Earth in 2068.

Apophis is about 1100 feet across — big enough to cause major damage if it hit. When it was discovered, in 2004, early calculations showed it might do just that — in 2029, ’36, or ’68. The first two possibilities were ruled out quickly, but the third persisted until this year.

Although it won’t hit us, Apophis will get close. In 2029, it’ll pass less than 20,000 miles away. And some teams of scientists want to take advantage of that approach. They’re drafting plans to send small satellites to intercept the asteroid.

Apophis Pathfinder would be launched a few years before the encounter. Two small probes would tag along with Apophis well before it gets here. They’d help define its orbit, measure its mass, map its surface, and more.

Another mission, Reconnaissance of Apophis, would launch a little later. A single spacecraft would look for changes as the asteroid flies past Earth. Watching those changes could help us better understand how asteroids behave as they orbit the Sun. That’s especially important for Apophis, which still could be a threat — but not over the next century.

Script by Damond Benningfield

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