Hopping rockets and flying washing machines in Google's wacky race to moon

Five competitors remain in a $20m Google contest to land a probe on the lunar surface by the end of the year, but all their craft are untested, rudimentary, or look like R2-D2

By the end of the year, space engineers hope to fulfil one of their greatest dreams. They plan to land a privately funded probe on the moon and send a small robot craft trundling over the lunar surface. If they succeed they will open up the exploitation of the moon for mining and ultimately human colonisation - and earn $20m prize money as winners of the Google Lunar XPrize.

Out of the 29 companies that originally entered the competition, only five remain in contention. Each has until the end of 2017, the XPrize deadline, to launch its robot mission.