Google sponsors moon landing prize

"We're starting on steps that will eventually lead to permanent settlement of the moon and Mars," Worden said. "That's probably going to get led by the private sector."

To help aspiring lunar explorers, startup launch services firm Space Exploration Technologies (SpaceX) of El Segundo, Calif., is offering to fly contestants' rovers on its Falcon rockets at cost, which would be about $7 million for its smallest booster.

"I'm a huge believer in us becoming a space-faring civilization," said SpaceX founder Elon Musk, the creator of Internet payments scheme PayPal.