The Moon has been shown to have a "tail" of sodium atoms too faint to be detected by the human eye. Hundreds of thousands of kilometers long, the feature was discovered in 1998 as a result of scientists from Boston University observing the Leonid meteor shower.[1][2]

The Moon is constantly releasing atomic sodium as a fine dust from its surface due to photon-stimulated desorption, solar wind sputtering, and meteorite impacts.[3] Solar radiation pressure accelerates the sodium atoms away from the Sun, forming an elongated tail toward the antisolar direction.

The continual impacts of small meteorites produce a constant "tail" from the Moon, but the Leonids intensified it,[4] thus making it more observable from Earth than usual.[5]

ISRO's Chandrayaan-2 recently[when?] discovered an abundance of sodium on the Moon.[6]

See also


  1. ^ "Astronomers discover that moon has long, comet-like tail". CNN. 1999-06-07. Retrieved 2007-12-18.
  2. ^ "The Sodium Tail of the Moon". NASA. 2009-12-01. Retrieved 2017-10-20
  3. ^ Matta, M. Smith; Smith, S.; Baumgardner, J.; Wilson, J.; Martinis, C.; Mendillo, M. (December 1, 2009). "The Sodium Tail of the Moon". Icarus. NASA. 204 (2): 409–417. Bibcode:2009Icar..204..409M. doi:10.1016/j.icarus.2009.06.017 – via ScienceDirect.
  4. ^ "Lunar Leonids 2000". NASA. 2000-11-17. Archived from the original on 2007-11-26. Retrieved 2007-12-18.
  5. ^ "Moon's tail spotted". BBC. 1999-06-09. Retrieved 2009-11-15.
  6. ^ "Chandrayaan-2 Orbiter Maps An 'Abundance of Sodium' On the Moon's Surface for the First Time Ever; Here's What It Means". The Weather Channel. Retrieved 2022-11-08.