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 just one large elliptical galaxy surrounded by considerable X-ray-emitting plasma much like an intracluster medium (ICM). It is presumed that the galaxies of a former group merged to form the remaining galaxy.


(galaxy clusters,galaxies)
Further reading:
https://en.wikipedia.org/wiki/Galaxy_group#Fossil_groups
https://astronomy.swin.edu.au/cosmos/F/Fossil+Groups

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