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Hawaii to Play Key Role in LCROSS Moon Mission

LCROSS heads for Moon

As LCROSS approaches the Moon, the Shepherding Spacecraft and rocket will separate. First the rocket and then the spacecraft will impact the Moon, creating a debris plume that will rise above the lunar surface. The impacts will be timed so that they can be observed with the large telescopes on Mauna Kea. Courtesy NASA.

The Lunar CRater Observation and Sensing-- LCROSS--mission will attempt to answer the question, Is there water on the Moon? Telescopes in Hawaii will play a key role in the mission.

It is important to find water before people return to the Moon because it would be impractical to transport large quantities of water from Earth. Previous space missions have detected hydrogen inside lunar craters near the Moon's poles. While the Sun's heat would have caused most water near the Moon's surface to evaporate long ago, these craters are permanently shadowed, so water ice may still exist there.

A rocket will launch LCROSS together with another spacecraft called the Lunar Reconnaissance Orbiter (LRO). Launch is now scheduled for the period June 17-21. The LRO, which will orbit the Moon for a year, will separate from the LCROSS after launch. LCROSS will consist of the upper stage of the rocket, which will act as the impactor, and the Shepherding Spacecraft, which will guide the rocket through multiple 38-day orbits of the Earth-Moon system. This will give scientists time to select and target a crater with great precision. Sometime between October 7 and 11, the impactor will separate from the spacecraft and hit the lunar South Pole at more than twice the speed of a bullet. While this is happening, the cameras on the Shepherding Spacecraft will photograph the rocket's descent and impact into the Moon. Four minutes later, the Shepherding Spacecraft will descend through the dust plume and analyze it with instruments that will be looking for evidence of water. The Shepherding Spacecraft will transmit the data back to Earth before it too hits the Moon.

Our view of the impacts will be obscured by the crater's rim. However, ground-based and orbiting observatories (including LRO) will observe the dust and, if present, the water vapor plumes caused by the two impacts. The impact cloud, which should rise more than three miles (6 km) above the lunar surface, should be visible from Earth several seconds after impact and peak in brightness 30-00 seconds after impact. The impacts will be timed so that they can be observed with the large telescopes on Mauna Kea, including the NASA Infrared Telescope Facility, the W. M. Keck Observatory, Gemini North, Subaru, and the Canada-France-Hawaii Telescope. Those with telescopes as small as 10-12 inches (25-30 cm) should also be able to see the impact cloud.

Amateur astronomers and students in Hawaii will participate in the mission. After launch, they will assist with observations that will characterize the impact target, which will be chosen after launch, so that NASA knows exactly where to aim the spacecraft. Some Hawaii students will be able to use the Faulkes Telescope North on Maui and the Goldstone Apple Valley Radio Telescope (GAVRT), a 34-meter dish that is part of NASA's Deep Space Network, to follow the progress of LCROSS from their classrooms and help NASA monitor spacecraft health and status. Amateur astronomers will also observe the impact. Several IfA staff members, including Technology Education and Outreach Specialist JD Armstrong and Optics/Electronics Engineer Joe Ritter on Maui, and Science Education and Public Outreach Officer Gary Fujihara and NAI Postdoctoral Fellow Josh Walawender in Hilo are working with the groups of amateur astronomers and students to prepare for the mission.

The LCROSS mission will actively solicit images of the impact from the public. These images will provide a valuable addition to the archive of data chronicling the impact and its aftermath. The LCROSS website will include a gallery of images received from both the public and professional communities.

LCROSS website

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