More than 40 years after the last Apollo astronauts left the moon, NASA is preparing to launch a small robotic spacecraft to investigate one of their most bizarre discoveries.
Crews reported seeing an odd glow on the lunar horizon just before sunrise. The phenomenon, which prompted a notebook sketch by Apollo 17 Commander Eugene Cernan, was unexpected because the airless moon lacked atmosphere for reflecting sunlight.
Scientists began to suspect that dust from the lunar surface was being electrically charged and somehow lofted off the ground, a theory that will be tested by the U.S. space agency's upcoming Lunar Atmosphere and Dust Experiment.
The spacecraft, known as LADEE, is scheduled to be launched at 11:27 p.m. EDT on Friday from NASA's Wallops Flight Facility on Wallops Island, Virginia.
"Terrestrial dust is like talcum powder. On the moon, it's very rough. It's kind of evil. It follows electric field lines, it works its way in equipment. ... It's a very difficult environment to deal with," said LADEE project manager Butler Hine of NASA's Ames Research Center in Moffett Field, California.
In addition to studying fly-away lunar dust, LADEE will probe the tenuous envelope of gases that surrounds the moon, a veneer so thin it stretches the meaning of the word "atmosphere."
Instead, scientists refer to these environments as exospheres and hope that understanding the moon's gaseous shell will shed light on similar pockets around Mercury, asteroids and other airless bodies.
"LADEE is part of a much broader scientific exploration of the solar system," said John Grunsfeld, NASA's associate administrator for science ( via news.yahoo.com ).