As Ulysses ends its mission to the sun, another spacecraft begins orbiting the moon. After flying through space for four and a half days, NASA?s Lunar Reconnaissance Orbitor [LRO] reached the moon and was positioned into a 200 km polar Earth orbit. The US space agency launched the Lunar Crater Observation and Sensing Satellite [LCROSS] on a mission to confirm the presence or absence of water in a permanently shadowed crater at the Moon?s South Pole. To that end, the goal is for LCROSS, its attached Centaur upper stage rocket, and all its sophisticated instruments to literally crash into the moon.
Several rocket burns put it on target for impact on October 9, 2009. On June 27, LRO was securely in its commissioning orbit. Craig Tooley, LRO project manager at NASA’s Goddard Space Flight Center sat in the control room as engineers powered up and calibrated LRO?s instruments and systems. Calibration was accomplished by scanning three sites on the lunar surface, plus the lunar horizon. In two months, LRO will transition into its permanent orbit until it is sent crashing into the moon. The purpose of the impending collision is to create debris plumes that will be analyzed for the presence of water ice or water vapor, hydrocarbons and hydrated materials.
In addition to some sophisticated instruments, what might be characterized as a type of time capsule went along for the ride. Over one million people submitted their names to be included on a microchip that went to the moon with the space ship. The microchip is encased in a radiation hardened container and attached to the back of the propulsion module access panel.
Everyone wants to be involved in the project, but the scientists and engineers are at the heart of the mission. "Our job is to perform reconnaissance of the moon’s surface using a suite of seven powerful instruments," Tooley said. "NASA will use the data LRO collects to design the vehicles and systems for returning humans to the moon and selecting the landing sites that will be their destinations."
To glean that information, the LCROSS science payload [LCROSS equipment description PDF download] consists of two near-infrared spectrometers, a visible light spectrometer, two mid-infrared cameras, two near-infrared cameras, a visible camera and a visible radiometer. The LCROSS instruments were selected to provide mission scientists with multiple views of the flash of light and debris plume created by the Centaur impact.
A set of lasers will be bounced off the surface of the moon to make a detailed map of the moon?s topography, its lunar craters, hills and boulders. Cameras will take pictures that can resolve details less than one yard across.
Diviner, an instrument built by the Jet Propulsion Laboratory, will be used to make a temperature map of the moon, looking into recesses of shadowed polar craters where the temperature can range from a cold of minus 370 degrees Fahrenheit. It will also test the equator where it can get as hot as 240 degrees under the sun’s radiation.
Several well-known companies participated in the project. Ames manages the mission, conducting mission operations. They developed the payload instruments and their scientists will spearhead the data analysis. Northrop Grumman designed and built the spacecraft for this ambitious mission.