NASA has launched a new lunar mission that is aimed at paving the way for astronauts to return to the moon's surface by 2020. The goal is to map new landing sites and search for water and other potential resources.
U.S. astronauts first set foot on the moon nearly 40 years ago, during the historic Apollo 11 mission led by Neil Armstrong.
"Houston, Tranquility Base here. The Eagle has landed," he announced a the time.
The Apollo 11 mission pushed the boundaries of planetary science, but it left some questions unanswered, such as whether there is water on the moon.
NASA hopes to answer that question and others with a two-part mission launched on a rocket from Kennedy Space Center in Florida.
The rocket is carrying the Lunar Reconnaissance Orbiter, which will collect data on temperature, terrain and other qualities in the polar region. NASA officials said one goal is mapping the area to find landing sites for future manned missions as early as 2020.
LRO scientist Rich Vondrak said the poles would be the best site for astronauts to gather sunlight for heat and for solar energy.
"We know there is one important resource there and that is nearly continuous sunlight" he said.
The second part of the mission is the Lunar Crater Observation and Sensing Satellite, or LCROSS, which will descend to the surface of the moon.
Principal investigator Tony Colaprete said the project is targeting areas that are constantly shadowed from sunlight.
"How do you get something that has been in the dark for maybe two billion years out to study it? We use the Centaur, a 2300 kilogram dead weight as an impacter," he said.
Colaprete said two Centaur weights will smash into the moon's surface, creating an explosion of material, which then can be analyzed by cameras and other tools.
A chief goal of LRO and LCROSS is to locate water, which could be a valuable resource to astronauts or scientists working on the moon's surface.
For years, scientists like Erik Hauri of the Carnegie Institution for Science in Washington have been searching for proof of water on the moon.
"It becomes prohibitively expensive to bring water to the Moon from the Earth, so if we can find any water on the moon to mine, then that gives the lunar outpost idea a big boost," he said.
Last year, Hauri was part of a team which proved for the first time that water is present in volcanic fragments brought back by Apollo astronauts. The project used highly sensitive tools to discover minute quantities of water in the glass-like beads.
"That's not a lot of water. It would be prohibitive to mine drinkable water from rocks with that little water. But we think magma had a lot more water at the time they were erupting," he said.
If larger quantities of water existed on the moon millions of years ago, scientists say then some of it may remain in the form of ice.
Last year, NASA's Phoenix Mars Lander collected samples of water ice for the first time on the surface of Mars. NASA officials said a similar discovery on the moon would bring a key boost for future exploration of Earth's closest neighbor.