Nasa Dart spacecraft to smash into asteroid to ‘prepare’ Earth

Nasa is to crash one of its spacecrafts into an asteroid to see how hard it would be to protect Earth against potential asteroid or comet hazards.

The space agency’s Double Asteroid Redirection Test (Dart) spacecraft will intentionally crash into Dimorphos about 12.14am UK time on Tuesday.

While the asteroid poses no threat to Earth, this is the world's first test of the technique using a spacecraft to deflect an asteroid for planetary defence.

“This test will show a spacecraft can autonomously navigate to a target asteroid and intentionally collide with it to change the asteroid’s motion in a way that can be measured using ground-based telescopes,” Nasa said in a statement.

“Dart will provide important data to help better prepare for an asteroid that might pose an impact hazard to Earth, should one ever be discovered.”

Live coverage of the event will begin at 11pm BST, on Monday with a briefing from the the Johns Hopkins Applied Physics Laboratory (APL). The labratory is the builder and manager of the spacecraft for Nasa.

Nasa has been able to “pinpoint” the location of the asteroid, Dimorphos, by taking hundreds of images over July and August.

Using observations taken every five hours, the Dart team moved the spacecraft towards the asteroid to “further reduce the margin of error for the spacecraft’s required trajectory to impact”.

After the final manoeuvre on Sunday, roughly 24 hours before impact, the navigation team could pinpoint Dimorphos within 2km.

From there, Dart - which weighs 570kg - will be on its own to autonomously guide itself to its collision with the asteroid moonlet, Nasa said.

Dart will be returning images to Earth at the rate of one per second as it heads towards the impact. What at first will appear as a dot of light in the pictures will quickly grow to fill the entire field of view, before the feed then suddenly cuts out as the spacecraft is destroyed.

Dart has carried with it a 14kg cubesat which will record what happens. Its pictures, taken 50km from the action, will be beamed back to Earth over the coming days.