Two NASA Moon Probes Head to Launch Site

Two spacecraft are headed for NASA's Florida space center to prepare for their piggyback mission to the moon.

NASA's Lunar Crater Observation and Sensing Satellite, known as LCROSS, set out from Northrop Grumman's facility in California this week for the agency?s Kennedy Space Center spaceport in Cape Canaveral Fla. Meanwhile, NASA's Lunar Reconnaissance Orbiter (LRO) — which will launch with LCROSS — was also expected to make the same trip.

The two unmanned spacecraft are the first in NASA's plan to return humans to the moon and begin establishing a lunar outpost by 2020. LCROSS will aim a double sledgehammer at the moon to search for water ice in a permanently shadowed crater near one of the lunar poles. LRO will spend at least one year in a low polar orbit on its primary exploration mission, with the possibility of three more years to collect additional detailed scientific information about the moon and its environment.

The joint LCROSS/LRO mission is currently slated to launch on April 24. This follows a delay of its planned launch late last year, in order to give priority to a military payload for a United Launch Alliance Atlas 5 rocket.

"This is the culmination of four years of hard work by everyone on the LRO Project," said Cathy Peddie, LRO deputy project manager at NASA's Goddard Space Flight Center in Maryland. "LRO now begins its launch site processing, where it will be prepped for integration with our sister mission LCROSS, and eventually encapsulated in the Atlas 5 for its journey to the moon."

After launch, the LCROSS spacecraft and the Centaur upper stage of its Atlas 5 rocket are designed to fly by the moon and enter into an elongated orbit to position the spacecraft for impact.

On final approach, the spacecraft and Centaur will separate, with the Centaur stage expected to strike a pre-selected lunar crater, creating a debris plume that should rise above the surface. Four minutes later, LCROSS would fly through the debris plume, collecting and relaying data back to Earth before striking the moon's surface and creating a second debris plume. Scientists will use data from the debris clouds to determine the presence or absence of water ice.

LCROSS?s sister spacecraft LRO will carry seven instruments to provide scientists with detailed maps of the lunar surface and enhance understanding of the moon's topography, lighting conditions, mineralogical composition and natural resources. Information gleaned from LRO will be used to select safe landing sites, determine locations for future lunar outposts and help mitigate radiation dangers to astronauts.

The polar regions of the moon are the main focus of the mission because continuous access to sunlight may be possible and water ice may exist in permanently shadowed areas of the poles.

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