Editor's note (Jan. 24): The XPRIZE Foundation confirmed on Tuesday that five teams remain in the competition for the Google Lunar XPrize. Contenders will now have until Dec. 31 for their spacecraft to be launched. Previously, the missions had to be completed by then.
It has taken five years longer than expected, but a competition intended to spark commercial development of the moon is in the home stretch, with at least five teams aiming to land robotic spacecraft on the lunar surface before the end of the year.
The first vehicle to successfully complete a series of tasks on the moon, such as sending back video and flying, rolling or hopping to a second lunar touchdown, will clinch a $20 million cash price.
The contest, backed by Google, is one of nine ongoing tournaments developed by the non-profit XPRIZE Foundation, which seeks to advance private sector development of aerospace, medicine, environmental health and other technologies with cash incentives for specific achievements.
The first, best-known and perhaps most audacious contest was to develop a reusable, manned spaceship that could travel in suborbital space. Billionaire Paul Allen, a co-founder of Microsoft, and Scaled Composites, now wholly owned by Northrop Grumman, won the $10 million Ansari XPRIZE in 2004. The vehicle, SpaceShipOne, became the model for a commercial passenger ship developed and currently undergoing testing by Richard Branson's Virgin Galactic.
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The Google Lunar XPRIZE aims for higher ground. To win the contest, a contender needs to land a spacecraft on the moon; have it fly, drive or hop at least 500 meters (1640feet); and relay high-resolution pictures and video back to Earth, all by Dec. 31, 2017.
The first team to do so wins $20 million. Second place is worth $5 million and bonus money is available for other milestones, such as traveling five kilometers (3.1 miles), touching down near an Apollo or other historic site, finding evidence of water and/or operating on two different lunar days. (A day on the moon lasts 27.3 Earth days.)
Teams' funding must be at least 90 percent from non-government entities.
After extending the original 2012 deadline three times, the XPRIZE Foundation on Tuesday will unveil which teams remain in the running. So far, the foundation has verified launch contracts for five contenders. They are:
The finalists have one less team to worry about. U.S. based Astrobotic, once considered a front-runner, decided late last year the Google Lunar XPrize no longer fit into its business plans.
"Things are really good right now. We are no longer planning to compete for the GLXP, but we remain totally committed to flying commercial lunar delivery missions," said chief executive John Thornton.
The Google Lunar XPrize was announced in 2007.
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