0 one of the independent groups of stars in the universe --
Present tonight at the long-awaited opening of this film are a whole galaxy of stars from the acting and musical professions.
1 one of the large, independent groups of stars in the universe --
The possibility of this happening is about as likely as humans walking the surface of planets of distant galaxies.
We read how the galaxies are grouped in clusters.
Such a large axion density would be incompatible with the formation of galaxies and so is anthropically disallowed.
There must have been something there to contribute to the gravity needed to keep the stars and galaxies gravitationally bound to their system.
Perhaps the strongest form of evidence for the existence of dark matter is the rotation curves of galaxies.
Such a regime may hold at the centre of galaxies or close to collapsed stars.
Quasars are widely believed to be the cores of young galaxies.
I have distinguished three sorts of galaxies, but it remains an open question which of the three types are instantiated.
