Here's why our moon is engulfed in permanent, lopsided dust cloud

New research shows that moon is engulfed in a permanent but lopsided dust cloud that increases in density when annual events like the Geminids spew shooting stars

Hints of the moon's halo date back to the late 1960s and NASA's Apollo program, but this permanent veil of dust was first characterized in 2014 with the help of data from NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft.

And now University of Colorado Boulder scientists say that the cloud, composed primarily of tiny grains kicked up from the lunar surface by the impact of interplanetary dust particles, increases in density whenever meteor showers and other celestial events boost the volume of the particles striking the moon.

Study leader Mihaly Horanyi said that identifying this permanent dust cloud engulfing the moon was a nice gift from this mission, adding that they can carry these findings over to studies of other airless planetary objects like the moons of other planets and asteroids.

Knowledge of the dusty environments in space has practical applications, said Horanyi. Knowing where the dust is and where it is headed in the solar system, for example, could help mitigate hazards for future human exploration, including dust particles damaging spacecraft or harming astronauts.

The study appears in Nature.