Google, the web search giant, joined today the XPrize Foundation in announcing the Google Lunar X Prize, which will be awarded to the first private company that will be able to land a privately funded robotic rover on the Moon. The Google Lunar X Prize was announced at the Wired NextFest in Los Angeles.

But just a landing will not be enough in order to claim the prize, because Google and XPrize Foundation said that the rover will need to complete several mission objectives, including roaming the lunar surface for at least 500 meters and sending video, images and data back to the Earth.

In fact, the $30 million prize purse is segmented into a $20 million Grand Prize, a $5 million Second Prize and $5 million in bonus prizes.

If a company will be able to make a rover that will land on the Moon until December 31st 2012, then it can claim the Grand Prize of $20 million. But if the mission will be completed until December 31st 2014, then the Grand Prize it will be worth only $15 million. On December 31st 2014 the competition will be terminated.

In order to win the $5 million Second Prize, the spacecraft will need to transmit images and data back to Earth. The rest of the money represent bonus prizes for successfully completing additional mission tasks such as roving longer distances (> 5,000 meters), imaging man made artifacts, discovering water ice, and/or surviving through a frigid lunar night (approximately 14.5 Earth days).

As Google announced the imagery and other data sent by the rover from the Moon would be shared with the world via the Google Lunar X Prize's Web site.

“The Google Lunar X PRIZE calls on entrepreneurs, engineers and visionaries from around the world to return us to the lunar surface and explore this environment for the benefit of all humanity,” said Dr. Peter H. Diamandis, Chairman and CEO of the X PRIZE Foundation. “We are confident that teams from around the world will help develop new robotic and virtual presence technology, which will dramatically reduce the cost of space exploration.”

“Having Google fund the purse and title the competition punctuates our desire for breakthrough approaches and global participation,” continued Diamandis. “By working with the Google team, we look forward to bringing this historic private space race into every home and classroom. We hope to ignite the imagination of children around the world.”

With this prize announced one thing it’s sure: Google loves space. Last month Google introduced a new feature in its Google Earth program, called Sky. Sky combines high resolution imagery and informative overlays in order to create a unique playground for visualizing and learning about space. The images used to recreate the sky are offered the Space Telescope Science Institute (STScI), the Sloan Digital Sky Survey (SDSS), the Digital Sky Survey Consortium (DSSC), CalTech’s Palomar Observatory, the United Kingdom Astronomy Technology Centre (UK ATC), and the Anglo-Australian Observatory (AAO).

Thanks to its collaboration with NASA Google has already launched, Google Mars and Google Moon, two projects similar to Google Earth.

"Why does Google love space? Well, for one thing, we just think it's cool," Alan Eustace, senior vice president of engineering at Google, said in a blog post. "More seriously, space exploration has a remarkable history of producing technological breakthroughs, from ablative heat shields and asteroid mining to invisible braces and Tang; the X Prize, too, could lead to important developments in robotic space exploration, a whole host of new Space Age materials, precision landing control technology and who knows what else."

Also Google co-founders said they are honored to sponsor the XPrize Foundation's project ."It's a great honour to participate in the Google Lunar X Prize," said Sergey Brin. "We are embarking upon this great adventure of having a nongovernmental, commercial organization return to the moon and explore."

"I hope that a ... very ambitious team of people will allow us all to virtually go back to the moon very soon. I couldn't be more excited about that," Larry Page said at WIRED show in Los Angeles.

The X Prize Foundation is known for its prizes offered to encourage privately funded research groups. In 2005 the foundation announced $10 million Ansari X Prize for the first private company that will build and launch a a reusable manned spacecraft into space twice within two weeks. The prize was won by a space SpaceShipOne designed by Burt Rutan and financed by Microsoft co-founder Paul Allen. Later SpaceShipOne flights inspired Richard Branson's Virgin Group to build a fleet of commercial suborbital spacecraft for Virgin Galactic.

In 2006 XPrize Foundation announced another prize, the $10m Archon X-Prize for Genomics, which will be given to the first private research group to sequence 100 human genomes in 10 days.

According to AP famed roboticist William "Red" Whittaker of Carnegie Mellon University has already expressed his interest for XPrize. He said is putting together a team to build a lunar rover. Last year, Whittaker was in charge of two autonomous vehicles that competed in a robot race across the Mojave Desert.

Back in the 60’s the race to the Moon was a fierce competition between the United States and the Soviet Union and the first era of lunar exploration reached a dramatic conclusion in December of 1972 as Apollo 17 Astronauts Captain Gene Cernan and Dr. Harrison Schmitt became the last men on the Moon.

Now the space agencies and governments from all around the world are competing again in order to send probes to the Moon.

Earlier this month Roskosmos, the Russian space agency, announced it that its plans for the future include a manned mission to the Moon. Anatoly Perminov, the head of Roskosmos, said that Russia plans to send a manned mission to the Moon by 2025. Also Russia has plans to build a permanent manned base on lunar soil, until 2032.

NASA is planning to launch an unmanned mission to the Moon in the fall of 2008. Lunar Reconnaissance Orbiter is a robotic mission designed to create a new type of comprehensive, digital map of the Moon's features and resources, necessary to cost-effectively, but mostly will focus on selecting safe landing sites for future human missions. Also NASA hopes to return the Moon by 2020.

The other countries are also considering unmanned missions. Earlier this year British space scientists have said they plan to undertake the country's first mission to the moon by the end of the decade. Germany also plans an unmanned flight to the moon by 2013. Beside Germany and UK, China, Japan, India and Italy have similar plans.

As XPrize Foundation explained in its press statement there are numerous reasons tot explore the Moon.

For example the Moon can be useful in launching other missions. Space exploration is expensive because every ounce of propellant and spacecraft must be launched out of the Earth’s strong gravity field. A natural storehouse of materials, lunar soil is more than 40% oxygen by weight and oxygen makes up most of the mass of rocket propellant. Because of its shallower gravity well, the Moon is the stepping stone to the universe.

The Moon can be also a platform for astronomical observation unhindered by atmosphere. The far side of the Moon is the one “quiet” place in the Solar System that is shielded from the Earth’s cacophony of radio, television and data broadcasts. The body of the Moon itself provides this shielding, and a radio telescope on the lunar far side can detect energy from the beginning of the universe.