European Space Agency is planning to launch a mission to assess whether it would be possible to save Earth, should we discover that an asteroid is on a collision course with our planet.

if it goes ahead in 2015, will see a satellite fired at break-neck speed into a ‘test’ asteroid to see if its course changes.

The mission, called Don Quijote, will involve sending two spacecraft towards a near-Earth asteroid.

One will be an ‘impactor’, which is fired into the asteroid, the other an orbitor that will analyse data from the experiment.

One potential target is a 1600ft-wide asteroid called 99942 Apophis, which experts say does have a minute chance - around one in 250,000 - of hitting Earth in 2036, so it would be useful target practice.

The 500kg impact craft, which will be called Hidalgo, will ram into the asteroid at a speed of around six miles a second.

The orbitor, called Sancho, will scan the collision and monitor whether the asteroid changes direction at all.