Astrophysics (Index)About

fossil group

(apparent remnant of a galaxy group)

A fossil group (fossil galaxy group) is what appears to have been a galaxy group, consisting of a large elliptical galaxy surrounded by X-ray-emitting plasma much like an intracluster medium (ICM). It is presumed that the galaxies of the group merged to form the remaining galaxy.

(galaxy clusters,galaxies)
Further reading: