Stellar association

Main associations of the galactic plane in the night sky

A stellar association is a very loose star cluster, looser than both open clusters and globular clusters. Stellar associations will normally contain from 10 to 100 or more visible stars. An association is primarily identified by commonalities in its member stars' movement vectors, ages, and chemical compositions. These shared features indicate that the members share a common origin. Nevertheless, they have become gravitationally unbound, unlike star clusters, and the member stars will drift apart over millions of years, becoming a moving group as they scatter throughout their neighborhood within the galaxy.[1]

Stellar associations were discovered by Victor Ambartsumian in 1947.[2][3][4] The conventional name for an association uses the names or abbreviations of the constellation (or constellations) in which they are located; the association type, and, sometimes, a numerical identifier.

  1. ^ Cite error: The named reference nao-cas was invoked but never defined (see the help page).
  2. ^ Lankford, John, ed. (2011) [1997]. "Ambartsumian, Viktor Amazaspovich (b. 1908)". History of Astronomy: An Encyclopedia. Routledge. p. 10. ISBN 9781136508349.
  3. ^ Cite error: The named reference baas29 was invoked but never defined (see the help page).
  4. ^ Saxon, Wolfgang (15 August 1996). "Viktor A. Ambartsumyan, 87, Expert on Formation of Stars". The New York Times. p. 22.