The lunar orbiter was launched earlier this year

Dec 16, 2009 19:01 GMT  ·  By

The Lunar Reconnaissance Orbiter (LRO) is one of the two Moon-bound spacecraft that NASA launched this June, aboard an Atlas V delivery system. While the LCROSS impactor already finished its mission, after slamming a spent rocket stage, and then itself, into the lunar south pole, the LRO is still returning valuable data, and will most likely continue to do so for a long time, officials at the American space agency say.

Speaking at the American Geophysical Union's meeting in San Francisco, experts from the Goddard Space Flight Center (GSFC), in Greenbelt, Maryland, presented the most recent findings made by three of the seven powerful scientific instruments aboard the orbiter. The science group added at the meeting that the LRO would most likely become the lunar equivalent of the Mars Reconnaissance Orbiter, which is to say it will send more data by itself than all other orbiting missions before it combined.

The Goddard team revealed new data collected via the LRO Camera (LROC), the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) and the Diviner Lunar Radiometer Experiment (Diviner) instruments. LROC has just recently finished photographing all of the Apollo landing sites, as well as the 50 patches of lunar soil that experts with Project Constellation determined to be representative of the landscape on the surface of the Earth's natural satellite. “From a practical, scientific standpoint, the Apollo landing sites have served as a fantastic source of calibration for the LROC Narrow Angle Cameras,” the LROC principal investigator, Mark Robinson, who is based at the Arizona State University, in Tempe, explained.

“Since the locations of some of the hardware left by the astronauts are known to about nine feet absolute accuracy, we can tie the Narrow Angle Camera geometric and timing calibration to the coordinates of the Apollo Laser Ranging Retroreflectors and Apollo Lunar Surface Experiments Packages. This ground truth enabled more accurate coordinates to be derived for virtually anywhere on the Moon,” he added. The camera also photographed the 50 Constellation sites with a spatial resolution of a meter or less, the scientist revealed.

“Scientists are currently analyzing brightness differences of the surface material stirred up by the Apollo astronauts, comparing them with the local surroundings to estimate physical properties of the surface material. Such analyses will provide critical information for interpreting remote sensing data from LRO, as well as from India's Chandrayaan-1, and Japan's Kaguya missions,” Robinson said. “The high-resolution images reveal a moon whose surface is geologically complex, scientifically compelling, and far more varied than one might expect on the basis of the limited number of landing sites from previous missions.”

The CraTER instrument is also playing an important part in the investigations, as it's currently trying to determine the level of radiations the Moon is exposed to. This will help NASA devise new methods of protecting its astronauts during future, planned missions to return to the satellite. “The rarest events – cosmic rays with enough energy to punch through the whole telescope – are seen once per second, nearly twice higher than anticipated. CRaTER radiation measurements taken during this unique, worst-case solar minimum will help us design safe shelters for astronauts,” the CRaTER principal investigator, Harlan Spence, shared. He holds a joint appointment, at the Boston University and the University of New Hampshire.

The Diviner instrument focused its attention on the lunar craters. It has determined that they are “brutally cold,” possibly the coldest places in the solar system, according to some analysts. The features are permanently shadowed, and the LRO was able to conclude that, during the mid-winter season, the temperature inside northern lunar craters dropped to about 26 Kelvin (-416 degrees Fahrenheit, or -249 degrees Celsius).

“These are the coldest temperatures that have been measured thus far anywhere in the solar system. These regions are cold enough to trap a wide range of compounds such as water, carbon dioxide, and organic molecules. There could be all kinds of interesting compounds trapped there,” University of California in Los Angeles (UCLA) scientist David Paige, the principal investigator of the Diviner instrument, said.

More details of the presentations can be found here.