CAPE CANAVERAL, Florida- Web search leader Google Inc. will sponsor a $30 million competition for an unmanned lunar landing, following up on the $10 million Ansari X Prize that spurred a private sector race to space.

Like the Ansari X Prize, which was claimed in 2004 by aircraft designer Burt Rutan and financier Paul Allen for a pair of flights by SpaceShipOne, the Google Lunar X Prize is open to private industry and non-government entities worldwide, organizers said before an official announcement on Thursday.

First prize is $20 million for the group that can land a lunar rover -- an unmanned robotic probe -- on the moon, take it on a 500 meter (1,640 ft) trek and broadcast video back to Earth by December 31, 2012.

The prize falls to $15 million if the landing takes place by December 31, 2014.

A second-place winner will receive $5 million. In addition, at least $5 million in bonuses are available for milestones such as finding relics from the U.S. Apollo moon landings, or from Soviet lunar explorations, detecting water ice or keeping the rover alive on the lunar surface overnight.

"Our hope is to educate and change public views about the moon," X Prize Foundation founder Peter Diamandis told Reuters in an interview last week. "The moon is an offshore island of Earth that has valuable resources which will benefit us as we grow as a species. We should look at it in that fashion."

The program was to be officially unveiled at Wired magazine's NextFest technology showcase, which opened Thursday in Los Angeles.

NASA had considered a similar venture as part of its Centennial Challenges program, but the agency so far has been able to fund prizes only up to $750,000. The NASA competitions also are closed to non-Americans.

"NASA is kind of an interested bystander," said Pete Worden, director of NASA's Ames Research Center in California and a longtime commercial space and lunar development advocate. "If a private company perfects a process to get payloads to the moon, NASA will have a lot interest in that."

The United States plans to retire its space shuttles in 2010 and develop new vehicles that can fly people to the International Space Station as well as the moon.

NASA, which landed six crews on the moon between 1969 and 1972 under the Apollo program, hopes to return astronauts to the lunar surface by 2020.

They may find it a busy place, as Russia, Japan, India and China have announced their own lunar ambitions.

SEEDING NEW INDUSTRY

Diamandis said he guessed four or five teams in the United States have the technical skills and financial backing to enter the race, and about the same number overseas. He estimated building, flying and operating a rover on the moon will cost between $20 million and $60 million.

It could seed a new industry. The SpaceShipOne flights paved the way for the construction of a fleet of commercial suborbital spacecraft for Virgin Galactic, an offshoot of Richard Branson's Virgin Group. Passenger service is expected to begin in 2009 or 2010.

"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.