Human survival could come down to Elon Musk after Nasa chose his space company to help to deflect asteroids that may one day hurtle towards Earth.

Nasa is planning to smash a spacecraft into an asteroid at high speed to see if it can alter its course. Mr Musk’s company will help to launch the spacecraft in question.

Nasa has announced that it will be using a rocket designed by Mr Musk’s space exploration company SpaceX, called Falcon 9, to take its asteroid-averting spacecraft into orbit.

The project is called Dart (Double Asteroid Redirection Test) and is being designed in a partnership with Johns Hopkins University in Baltimore, Maryland.

While asteroids the size of a table hit Earth all the time, what Dart is