NASA Science News has the scoop on a telescope that, believe it or not, is bigger than a galaxy.
… At the January 2014 meeting of the American Astronomical Society, researchers revealed a patch of sky seen through a lens more than 500,000 light years wide.
The “lens” is actually a massive cluster of galaxies known as Abell 2744. As predicted by Einstein’s Theory of General Relativity, the mass of the cluster warps the fabric of space around it. Starlight passing by is bent and magnified, much like an ordinary lens except on a vastly larger scale.
Lately, the Hubble Space Telescope, along with the Spitzer Space Telescope and the Chandra X-ray Observatory, has been looking through this gravitational lens as part of a program called “Frontier Fields.”
“Frontier Fields is an experiment to explore the first billion years of the Universe’s history,” says Matt Mountain from the Space Telescope Science Institute in Baltimore, Maryland. The question is, “Can we use Hubble’s exquisite image quality and Einstein’s theory of general relativity to search for the first galaxies?”
The answer seems to be “yes.” At the AAS meeting, an international team led by astronomers from the Instituto de Astrofísica de Canarias and La Laguna University discussed Hubble and Spitzer observations of the Abell 2744 cluster. Among the results was the discovery of one of the most distant galaxies ever seen—a star system 30 times smaller yet 10 times more active than our own Milky Way. Bursting with newborn stars, the firebrand is giving astronomers a rare glimpse of a galaxy born not long after the Big Bang itself.
Overall, the Hubble exposure of Abell2744 revealed almost 3,000 distant galaxies magnified as much as 10 to 20 times larger than they would normally appear. Without the boost of gravitational lensing, almost all of those background galaxies would be invisible.
Abell 2744 is just the beginning. Frontier Fields is targeting six galaxy clusters as gravitational lenses. Together, they form an array of mighty telescopes capable of probing the heavens as never before.