NASA announced plans today to crash a space probe into the moon in search of water.
The probe will hitchhike on a lunar orbiter that the agency aims to launch in late 2008.
The landing will be the first step in an effort by NASA to return humans to the moon and eventually establish a manned base there.
"This mission is an early attempt at getting to know what some of the resources are [on the moon] that are going to have large implications [for] what we do in the future of [space] explorations," said Scott Horowitz, the exploration chief for NASA, at a news conference in Washington, D.C.
The mission will be the first U.S. moon landing in 36 years.
In late January, NASA asked its 10 regional field centers to submit proposals for a spacecraft that could travel to the moon with the Lunar Reconnaissance Orbiter, which will be launched in October 2008.
The agency received 19 proposals.
Today NASA announced the winner of the competition: the Lunar Crater Observation and Sensing Satellite (LCROSS). A team at NASA's Ames Research Center in Moffett Field, California, will develop the spacecraft.
The LCROSS mission consists of an impact probe and a "shepherding" spacecraft.
The SUV-size probe will crash into one of the permanently shadowed craters located near the moon's south pole. (See and download a photo of the moon's surface.)
Evidence of abundant stores of hydrogen—a prime element of water—has been detected near the moon's poles by U.S. orbiters launched in the 1990s.
The probe's impact is expected to create a plume of debris that may vault 40 miles (65 kilometers) above the moon's surface.
The shepherding spacecraft will then fly through that plume. Its instruments will analyze the cloud to look for signs of water ice and other compounds.
"It's a big swath of material that we're kicking up, so it will give us a definitive understanding of what we have there," said Dan Andrews, the LCROSS project manager, at the news conference.
The mission will kick-start a new phase of unmanned lunar exploration, which will set the stage for humans' return to the moon by 2020, a goal set by the Bush Administration.
The LCROSS shepherding craft will make detailed maps of the lunar surface to identify possible landing sites for the planned return of U.S. astronauts.
"This is the first mission out of the gate for our program," said Butler Hine, deputy program manager for the Robotic Lunar Exploration program based at the Ames Research Center.
"This will create the fundamental maps that we need to accomplish the human mission."
Scientists also hope to identify resources on the moon that could eventually be used to establish a human presence the moon.
The presence of water is considered key to setting up a lunar base. Oxygen on the moon could be used as breathable air and as a component in rocket propellant.
"These resources can make future human occupation much more cost-effective," Hine said.
"If we can live off the land and use the resources that are available there, rather than lift them out of the Earth's gravity, then it becomes much less expensive."