APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
A Cluster Too Far
Explanation: Why is this galaxy cluster so red? Nearby clusters have galaxies with colors that are much more yellow and blue. A leading explanation is that this cluster of galaxies lies so far across our universe (z~1) that cosmological time dilation significantly reddens the light. If true, this cluster might lie too far away to have formed in a dense universe, implying that our universe is not very dense. HST 035528+09435 is one of the reddest clusters found in the Hubble Space Telescope 's Medium Deep Survey . Astronomers will now work to confirm the high distance to this cluster , and contemplate what it signifies about the nature of our universe .
| Date | September 8, 1998 |
|---|---|
| Credit | Credit: E. J. Ostrander et al. (Carnegie Mellon U.), WFPC2, HST, NASA |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |