Nasa boffins unveil ‘historic’ plan to redirect asteroid with amazing new defence technique

Nasa has unveiled a bold new plan to eliminate the threat of massive asteroids colliding with Earth by redirecting them.

The space agency is set to test its new defence system - Double Asteroid Redirection Test (Dart) - on the asteroid system named Didymos.

Asteroids hit Earth most days, however because they are so small they burn up in our planet's atmosphere.

However Nasa is determined to eliminate the threat of asteroids that are so big they won't burn up - potentially causing devastation.

The test will take place in 2022, as Nasa scientists work with the John Hopkins Applied Physics Laboratory.

Lindley Johnson, Nasa's planetary defense officer, said: "Dart would be Nasa's first mission to demonstrate what's known as the kinetic impactor technique - striking the asteroid to shift its orbit - to defend against a potential future asteroid impact.

"This approval step advances the project toward an historic test with a non-threatening small asteroid."

Didymos is set to near Earth in 2022 - at which time Nasa will launch a fridge-sized spacecraft towards it, hoping to change its direction.

The space agency said in a statement: "The kinetic impact technique works by changing the speed of a threatening asteroid by a small fraction of its total velocity.

"But by doing it well before the predicted impact so that this small nudge will add up over time to a big shift of the asteroid's path away from Earth."

Andy Cheng, one of the leaders of the Johns Hopkins team, added: "DART is a critical step in demonstrating we can protect our planet from a future asteroid impact.

"With Dart, we can show how to protect Earth from an asteroid strike with a kinetic impactor by knocking the hazardous object into a different flight path that would not threaten the planet."