How do galaxies grow?

Composite colour-image of the brightest galaxies in four groups located about 4 billion light-years away. The galaxies are ordered in increasing stellar mass, i.e. a rough time sequence. The brightest galaxies in group 1 and 2 both have obvious bright, gravitationally bound companions. Further images obtained with the Hubble Space Telescope shows that the brightest galaxy in group 3 has a double nucleus. Thus, these galaxies are currently in the process of merging. This discovery provides unique and powerful validation of hierarchical formation as manifested in both galaxy and cluster assembly.

Credit:

ESO

About the Image

Id:eso0824a
Type:Collage
Release date:26 August 2008
Related releases:eso0824
Size:1646 x 408 px

About the Object

Name:Galaxies
Type:Early Universe : Galaxy : Type : Interacting
Category:Galaxies

Image Formats

Large JPEG
184.2 KB
Screensize JPEG
91.3 KB