Rather than Hollywood’s preferred option, engineers are trying to develop unmanned rockets that can land on space rocks and use the asteroids’ own material to propel them into a safer orbit.
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“It is like throwing rocks out of a rowing boat on a lake. The rocks go in one direction and the boat is slowly pushed in the other under the laws of physics,” said John Olds, the chief executive of SpaceWorks, the firm behind the scheme. “Over several months we think we can make the difference between a hit and a miss.” Astronomers fear that a 400-yard wide asteroid will pass dangerously close to the Earth within 30 years. Typically, one the size of a football pitch strikes every 100 years or so, and it is also almost 100 years since the last major impact which caused an explosion equivalent to a 15 megaton nuclear bomb in Tunguska, Siberia on June 30, 1908.