2
7
A gigantic 'doomsday' asteroid is on course to slam into Earth in 2135 amid fears humans could be powerless to stop it without a new defence system.
The space boulder called Bennu is the size of a village and as tall as New York's Empire State Building.
There's a one in 2,700 chance it could crash into Earth on September 21, 2135, and wipe out life with an impact 23 times bigger than a hydrogen bomb blast.
Today's technology may not be advanced enough to stop the threat, but US space scientists have designed a concept spacecraft that would blow up or deflect oncoming asteroids with a nuclear explosion.