Scientists are trying to find a way to protect Earth from the giant rocks which travel around the Milky Way.

Run out of Berlin with funds from the EU, the NEOShield project, which will look for a way to protect earth from the space rocks, is expected to take three years to complete.

Some of the ideas being tossed around at the moment include repelling asteroids with projectiles or explosives or using gravity to change its course.

The project though is a little late as a chunk of rock 400 times the City of London is set to hurtle closer than a rock of its size has in a very long time.

The asteroid labelled ‘(433) Eros’ measures 19 by 8 by 8 miles and is set to pass by next week.

Despite its massive size, the cosmic rock shouldn’t be too cause too much of a threat as it is on a circular path far outside the moon"s orbit.

Nevertheless, with NASA estimating that there are almost one thousand asteroids over one kilometre in length and 19,500 over 100-metres, scientists at the Institute of Planetary Research are trying to find a way to protect Earth.

With an investment of some € million by the European Commission and an extra €.8 million coming from scientific institutions and partners, the German Aerospace Center aims to have a plan for a test mission drafted within three years.

After that, if they can find the extra cash, the mission may be launched by 2020. The scientists will be looking at a host of ideas, many of which have already been proposed.

"Of course, a lot of things have already been proposed," Alan Harris, the study’s leader, told Spiegel Online. ‘But, so far, most of them have come from a single institution, perhaps even from a single person. So it has been hard to pursue them.’

Investigating each idea ‘will take place on paper and in lab experiments, since we don"t have the money to do more than that,’ said Wolfram Lork, who works with a subsidiary on the project.

One other, coarser idea would be ‘blast deflection’ which would involve deterring the asteroid with directed explosive charges. Harris says this would be the ‘final, desperate approach.’