NASA Mission Reaches Moon

Four days after launch, the Lunar Reconnaissance Orbiter and the Lunar Crater Observation and Sensing Satellite reach their lunar destinations. The LRO will orbit the moon on a mapping mission while the LCROSS will crash into the surface in attempt to determine whether water ice actually exists on the moon.

NASA's Lunar Reconnaissance Orbiter successfully entered orbit around the moon June 23, four days after launching from Cape Canaveral along with its companion vehicle, the Lunar Crater Observation and Sensing Satellite. A series of four engine burns over the next four days will put the LRO into its commissioning phase orbit.

The primary objective of the LRO mission, which is scheduled for a one-year mapping exploration trip with the possibility of an additional three-year scientific mission, is to conduct investigations that prepare for future lunar exploration. NASA claims the LRO will return more data about the moon than any previous mission.

"Lunar orbit insertion is a crucial milestone for the mission," said Cathy Peddie, LRO deputy project manager at NASA's Goddard Space Flight Center. "The LRO mission cannot begin until the moon captures us. Once we enter the moon's orbit, we can begin to build up the data set needed to understand in greater detail the lunar topography, features and resources."

The LRO's commissioning phase will take approximately two months, after which the LRO will use its engines to transition to its primary mission orbit about 31 miles above the moon's surface. During the commissioning period, NASA engineers will check out each of satellite's seven instruments and bring them online.

According to NASA, the LRO will explore the "moon's deepest craters, examining permanently sunlit and shadowed regions, and provide understanding of the effects of lunar radiation on humans."

While the LRO orbits the moon to compile high-resolution, three-dimensional maps of the lunar surface, NASA plans to crash the LCROSS into the moon's surface to probe a permanently shadowed crater near one of the moon's poles. The idea is to answer the question of whether water ice actually exists on the moon. If the answer is yes, it could potentially be a useful resource for future exploration. The LCROSS mission is scheduled for three to seven months.

The LCROSS began beaming live photos from the moon June 23.

In addition to the planned LCROSS lunar impact, NASA will also guide an empty upper stage of the Atlas V launch rocket on a collision course with a permanently shaded crater in an effort to kick up evidence of water at the moon's poles. The empty Centaur rocket stage is currently coupled with the LCROSS.

The two vehicles will separate approximately 5 hours before impact at a height of 54,059 miles above the moon. At impact, the Centaur will be traveling at approximately 1.55 miles per second. The LCROSS impact will follow 4 minutes later.

The Centaur's impact will excavate more than 350 metric tons of lunar material and create a crater 66 feet in diameter to a depth of 13 feet. Most of the material in the Centaur debris plume will remain at altitudes below 6.2 miles. The LCROSS impact will excavate an estimated 150 metric tons, with a crater 46 feet in diameter to a depth of 6 feet.