Space

How to Divert an Asteroid the Size of Nine Cruise Ships: Destroy it with a Nuclear Warhead

Catherine Griffin
First Posted: May 29, 2013 08:55 AM EDT

There are some terrifying things out there in space, and an asteroid the size of nine cruise ships is one of them. The asteroid, known as 1998 QE2 will harmlessly sail past Earth on May 31. Yet what would happen if it was set on a trajectory toward our planet? Good question. The best idea NASA has come up with would be to destroy it with a nuclear warhead.

Asteroids can be devastating. Past impacts have caused climate change as debris was hurtled into the air, damage to the landscape and other issues. There are currently more than 1,300 potentially hazardous asteroids (PHAs) about 150 yards across that have a small chance of making an impact. Their orbital paths will take them close to Earth, but there's no guarantee that they'll crash land. But since asteroids move so quickly--about 27,000 to 33,000 miles per hour--relative to Earth, they carry enormous energy. This means that if one were to crash into Earth, there could be significant impacts.

This is why NASA is currently developing ways to divert and destroy asteroids that could hurtle toward Earth. The nuclear warhead method, though, is currently the best idea so far. It would work by launching an anti-asteroid spacecraft that would deliver the nuclear warhead in order to destroy an incoming threat before it could reach Earth. More specifically, the two-section spacecraft would consist of a kinetic energy impactor that would separate before arrive and blast a crater in the asteroid, according to Space.com. The other half of the spacecraft would carry the nuclear weapon, which would then explode inside the crater after the vehicle impacted.

Why a nuclear warhead? It's the only thing that would work against an asteroid on short notice, according to Space.com. In fact, other systems could take as much as 10 to 20 years advance notice.

The current asteroid that's set to swoop by Earth isn't a threat, of course. It will get no closer than about 3.6 million miles, which is 15 times the distance between the Earth and the moon. While it won't get too close for comfort, though, it will get close enough so that those who dabble in radar astronomy will have a nice target to image.

"Asteroid 1998 Q2 will be an outstanding radar imaging target at Goldstone and Arecibo, and we expect to obtain a series of high-resolution images that could reveal a wealth of surface features," said radar astronomer, Lance Benner, in a news release. "Whenever an asteroid approaches this closely, it provides an important scientific opportunity to study it in detail to understand its size, shape, rotation, surface features and what it can tell us about its origin."

While 1998 Q2 isn't a threat, though, other asteroids in the future might be. Blasting them out of the sky could potentially save Earth from a devastating impact, though whether it will actually work remains to be seen.

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