NASA will test a strategy to save the Earth by smashing a satellite into an asteroid

In a test of "planetary defence," NASA wants to crash a spaceship speeding at 15,000 mph (24,000 kph) into an asteroid next year.

The purpose of the Double Asteroid Redirection Test (DART) is to see if this is an efficient approach to deflect an asteroid's route if one ever threatens the Earth.

The DART spacecraft is set to launch from Vandenberg Space Force Base in California at 10:20 p.m. Pacific time on Wednesday aboard a SpaceX Falcon 9 rocket.

In a press event earlier this month, NASA disclosed details on the DART project, which is expected to cost $330 million.

"Although there isn't a currently known asteroid that's on an impact course with the Earth, we do know that there is a large population of near-Earth asteroids out there," said Lindley Johnson, NASA's Planetary Defense Officer.

"The key to planetary defense is finding them well before they are an impact threat," Johnson said. "We don't want to be in a situation where an asteroid is headed towards Earth and then have to test this capability."

If the launch goes as planned, the asteroid will collide with Earth between September 26 and October 1 next year, at a distance of 6.8 million miles.