NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) is now on station, orbiting the moon every two hours. The LADEE spacecraft comes to within 8 miles of the lunar surface at its closest point! That's what comes of a tenuous atmosphere.
(LADEE status video 2013)
LADEE's orbit carries the car-size spacecraft around the moon's equator, allowing the probe repeatedly see the moon during lunar day and night. Scientists hope it will be able to see strange, glowing "rays and streamers" in the moon's atmosphere that were first seen in early unmanned lunar photographs and reports from Apollo lunar landing astronauts.
Science fiction writers in the 1950's and 1960's were fascinated by the possibility that the moon might be covered in dust - no one knew how much - and how it would affect lunar exploration.
SF author Hal Clement predicted in a 1956 short story that electrostatically charged lunar dust particles might actually suspend themselves above the surface:
"…The [Moon's] surface material is one of the lousiest imaginable electrical conductors, so the dust normally on the surface picks up and keeps a charge. And what, dear student, happens to particles carrying like electrical charges?"
"They are repelled from each other."
(From Dust Rag, Astounding Science Fiction, 1956)
One of LADEE's mission parameters is to try to determine levels of dust in the thin lunar atmosphere.