History of our Universe
Copyright: A. Dressler (Carnegie Institutions of Washington), M. Dickinson (STScI), D. Macchetto (ESA/STScI), M. Giavalisco (STScI), and NASA
These galaxies existed in a rich cluster when the universe was approximately two-thirds its present age. Elliptical galaxies (top) appear fully evolved because they resemble today's descendants. By contrast, some spirals have a frothier appearance, with loosely shaped arms of young star formation. The spiral population appears more disrupted due to a variety of possible dynamical effects that result
from dwelling in a dense cluster.
Last Update: 1 September 2019