Mars Curiosity rover's 'crazy' landing system
30 July 2012 Last updated at 00:24 BST
Nasa's $2.5bn Curiosity rover mission relied on a revolutionary new landing system that even the mission team conceded looked a bit "crazy".
On descent, the rover was held in a rocket-propelled cradle which slowed itself to a halt and hover 20m above the surface of Mars to lower the rover down on nylon cables.
This clip from the BBC's Horizon programme was first broadcast 30 July 2012