Hubble image archive
A "Hubble Atlas" of Ancient Galaxies
Hubble Space Telescope's high resolution allows astronomers to classify galaxies in a cluster (CL 0939+4713) that existed four billion years ago, when the universe was two- thirds of its present age.The galaxies in this mosaic are arranged according to the well-established system...
- Date
- Jan 1, 1992
- Mission
- Hubble Space Telescope
- Archive ID
- hubblesite-images-1992-28-84-image
Hubble Space Telescope's high resolution allows astronomers to classify galaxies in a cluster (CL 0939+4713) that existed four billion years ago, when the universe was two- thirds of its present age.
The galaxies in this mosaic are arranged according to the well-established system developed by American astronomer Edwin Hubble in the 1920s. Despite the cluster's great distance of four billion light-years, the Space Telescope pictures are sharp enough to distinguish between various forms galaxies.
The top three rows show familiar types of galaxies which are found today in nearby clusters: elliptical galaxies and lens shaped galaxies (SO) which may be transition objects between spiral and elliptical galaxies.
Rows 4 through 7 show spiral galaxies categorized by the openness of their pinwheel- shaped arms (Hubble classification Sa, Sb, Sc, Sd). Many of these have since disappeared through possibly a variety of processes: merger, disruption, and fading. In particular the spirals in row 7 (Sd) show peculiar morphologies.
The bottom row shows galaxies apparently merging into single systems.
Space Telescope reveals that star-forming galaxies were far more prevalent in the clusters of the younger universe than in modern clusters, a result having important implications for theories of galaxy evolution.
The image was taken with HST's Wide Field/Planetary Camera in Wide Field Camera mode, and required a six-hour exposure.
Credits
Alan Dressier, Carnegie Institution, and NASA Co-investigators: Augustus Oemler (Yale Urnversfty), James E. Gunn (Princeton Universfty), Harvey Butcher (the Netherlands Foundation for Research in Astronomy).Image Details
| About The Object | |
|---|---|
| Object Name | CL 0939+4713 |
| R.A. Position | 09h 42m 56.59s |
| Dec. Position | 46° 59' 21.99" |
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Source
Image and source material are credited to the official mission archive linked below.
View on NASA.gov