Nasa’s Dart probe to smash into asteroid in first Earth defence test

Aim is to see whether space rocks can be deflected should one threaten humans with same fate as dinosaurs

Most mission scientists would wince at the thought of their spacecraft being smashed to smithereens. But for those behind Nasa's Dart probe, anything short of total destruction will be chalked up as a failure.

The $330m (300m) spacecraft is due to slam head-on into an asteroid about 11m kilometres above the Indian Ocean soon after midnight on Monday. The impact, at nearly seven kilometres a second, will obliterate the half-tonne probe, all in the name of planetary defence.