In its most violent mission so far, the US space agency Nasa slammed two probes into the moon, in the hope of detecting lunar ice in a plume of moondust.

But the event was an anticlimax for many thousands of people around the world watching live images on the internet as a two-tonne Centaur rocket hit the target. There was no sign of the expected flash or explosion and no obvious dust cloud rising from the impact zone, the Cabeus crater near the lunar south pole.