Frontier fields, a collaborative program for imaging distance celestial bodies has found a cluster of galaxies believed to have formed when the universe was very young, no more than 650 million years old. The program known as “frontier fields” is a collaboration between NASA and ESA (European Southern Observatory). The imaged cluster of galaxies is officially named Abell2744Y1; located in the constellation Sculptor nearly 3.5 billion light years away. This cluster is the result of at least four galaxies that collided in the distant past. Dubbed Pandora’s cluster by the astronomer community because of the chaotic mesh of galaxies seen in the images take by Hubble.
Pandora’s cluster is just the first of six galactic clusters that will be observed for the frontier fields program. These observations are possible because of what astronomers call gravitational lensing. A natural phenomena created when large celestial bodies, such as Abell2744Y1, warp light around them with their gravitational force. The result being whatever light is warped become magnified. This allows astronomers to peer into deep space where the faint light of these galaxies are hidden. Although this also creates some distortions to galaxies on the fringe of the gravitational lens. Some galaxies are duplicated while others appear to be blurred or smeared across the warped lens.
Lead astronomers from various universities and research institutions have used the Hubble telescope, NASA’s Spitzer infrared telescope and Chandra X-ray observatory to study the cluster. Astronomers hope to find clues as to how galaxies formed during the early stages of the universe, after the Big Bang.
Calculating the age of these galaxies is possible because of the great distance the light must travel. As the light travels farther from the observer, its frequency lengthens shifting it across the spectrum to a reddish hue. This is known as a redshift. The further the light source is, the more red it will appear. The last galaxy imaging program was known as “Deep Field” where they used the Hubble telescope to image nearly 3,000 previously unknown galaxies back in 1996. The redshift scale ranges from 1 to 12; the frontier fields cluster ranges from 8.5 to 12, the very dawn of the known universe.
“It is the deepest view of the universe ever taken,” Jennifer Lotz of the Space Telescope Science Institute of Baltimore says “We’re seeing things 10 or 20 times fainter than anything we’ve seen before.” The Hubble telescope takes nearly 5 hours exposer to adequately capture the faint light from the far off galaxies. Preliminary findings show that many of the galaxies in Pandora’s cluster are usually smaller and contain more stars than younger galaxies found. Many of the initial images from the program have already been released for the 223rd American Astronomical Society meeting in Washington, DC.
The frontier fields program will continue to study galactic clusters with the Hubble telescope for the next three years; as it orbits 840 times around the selected celestial bodies. For astronomers the study of ancient far off galaxies is a window to the past. When the universe was still violent, chaotic and full of energy. Theres no telling what secrets Pandora’s cluster will reveal to the frontier fields program but the possibilities have astronomers eager to look even further.
By Eric Ohm