Hubble Space Telescope Provides New Perspective

By  //  January 9, 2014

finds deepest cluster of galaxies ever found

This long-exposure Hubble Space Telescope image of massive galaxy cluster Abell 2744 (foreground) is the deepest ever made of any cluster of galaxies. It shows some of the faintest and youngest galaxies ever detected in space. (NASA.gov)
This long-exposure Hubble Space Telescope image of massive galaxy cluster Abell 2744 (foreground) is the deepest ever made of any cluster of galaxies. It shows some of the faintest and youngest galaxies ever detected in space. (NASA.gov)

NASA.gov — NASA’s Hubble Space Telescope is providing a new perspective on the remote universe, including new views of young and distant galaxies bursting with stars and scientists described the findings Tuesday in a news conference sponsored by the American Astronomical Society (AAS).

Normally too faint for Hubble to see, these galaxies were revealed through gravitational lensing focused on a massive galaxy cluster known as Abell 1689 in the constellation Ursa Major. The cluster magnified light emitted by distant objects behind it, causing the newly discovered galaxies to appear bigger and brighter. If this sample is representative of the entire population at the time, then the majority of new stars formed in such small, unseen galaxies. (NASA.gov image)
Normally too faint for Hubble to see, these galaxies were revealed through gravitational lensing focused on a massive galaxy cluster known as Abell 1689 in the constellation Ursa Major. The cluster magnified light emitted by distant objects behind it, causing the newly discovered galaxies to appear bigger and brighter. If this sample is representative of the entire population at the time, then the majority of new stars formed in such small, unseen galaxies. (NASA.gov image)

The immense gravity in Abell 2744 is being used as a lens to warp space and brighten and magnify images of more distant background galaxies. The more distant galaxies appear as they did longer than 12 billion years ago, not long after the big bang.

The Hubble exposure reveals almost 3,000 of these background galaxies interleaved with images of hundreds of foreground galaxies in the cluster. Their images not only appear brighter, but also smeared, stretched and duplicated across the field. Because of the gravitational lensing phenomenon, the background galaxies are magnified to appear as much as 10 to 20 times larger than they would normally appear. Furthermore, the faintest of these highly magnified objects is 10 to 20 times fainter than any galaxy observed previously. Without the boost from gravitational lensing, the many background galaxies would be invisible.

THE HUBBLE EXPOSURE TO BE COMBINED WITH OTHER IMAGES

The Hubble exposure will be combined with images from Spitzer and NASA’s Chandra X-ray Observatory to provide new insight into the origin and evolution of galaxies and their accompanying black holes.