January 8, 2014
Hubble Frontier Fields Mission Captures First Image Of Pandora’s Cluster
redOrbit Staff & Wire Reports - Your Universe Online
Abell 2744, a giant galaxy cluster believed to have formed when four smaller galaxy clusters crashed into one another, is the subject of the first image captured by Hubble's Frontier Fields observational program, NASA and ESA announced Tuesday.
Abell 2744, which was first observed by the Hubble Space Telescope in 2011, is also known as Pandora’s Cluster because the mixture of elliptical and colorful spiral galaxies that formed it resulted in some unusual, never-before-seen cosmic phenomenon, according to an ESA statement.
It is the first of six targets for Frontier Fields, a three-year, 840-orbit initiative that astronomers expect to provide the deepest views of the universe to date. The program will use the power of Hubble and a phenomenon known as gravitational lensing effects to explore distant regions of space that could not be seen otherwise.
Gravitational lensing, ESA explained, is caused by the influence an object has on the space-time that surrounds it. Massive objects such as galaxy clusters warp and distort this space-time, bending and deflecting light from distant objects hidden behind makeshift lenses. This can lead to a plethora of unusual optical effects.
The image, which was released Tuesday during the 223rd meeting of the American Astronomical Society (AAS) in Washington, DC, shows the elliptical and spiral galaxies clumping together in the picture’s center. The effects of the Pandora Cluster’s gravity can be seen in blue arcs and distorted shapes, which are actually distorted images of distant galaxies.
“Some results from this program are already starting to emerge, with Abell 2744 as the first target,” ESA said. A research paper submitted to The Astrophysical Journal in November 29, 2013 described how astronomers were able to use Abell 2744 like a lens in order to detect a large number of distant, gravitationally-lensed galaxy candidates.
NASA and ESA added that they found that five of those candidates “are part of distant systems that appear to have been imaged multiple times due to the cluster's gravitational lensing effects. These deep surveys using massive galaxy clusters like Abell 2744 show that looking through cosmic lenses can be an effective and useful way to study the distant Universe.”
The Hubble Frontier Fields mission, which got underway in October 2013, combines three of the most powerful space telescopes in the world (Hubble, Spitzer and Chandra) with naturally occurring “zoom lenses” in space. The goal is to locate galaxies up to 100 times fainter than could normally be detected by any of the three observatories alone.
“The Frontier Fields program is exactly what NASA’s great observatories were designed to do; working together to unravel the mysteries of the Universe,” explained John Grunsfeld, associate administrator for NASA’s Science Mission Directorate. “Each observatory collects images using different wavelengths of light with the result that we get a much deeper understanding of the underlying physics of these celestial objects.”