This is an interesting video about a thin layer of ionized dust above the lunar surface. Via NASA and SpaceWeather.com:
How can a world without air have an ionosphere? Somehow the Moon has done it. Lunar researchers have been struggling with this mystery for years, and they may have finally found a solution.
This reminds me of a joke a fellow student told me while I was in college: Astronauts were stranded on the moon. NASA told them, “Open your helmets. It will be quick.” They did, and replied, “O.K., Now what?”
More properly, it would have been, “They opened their helmets, took a deep breath, and said, ‘Now what?'”
Funny. I saw a sci-fi flick a while back (can’t remember the title) where one of the Mars-bound astronauts had a ‘quick’ experience when he opened his helmet. Good special effects but bad science. It looked like his face froze when in reality his head would have exploded.