Washington, March 4 (IANS) By pushing NASAs Hubble Space Telescope to its limits, an international team of astronomers has shattered the cosmic distance record by measuring the farthest galaxy ever seen in the universe.
This surprisingly bright infant galaxy, named GN-z11, is seen as it was 13.4 billion years in the past -- just 200-300 million years after the Big Bang.
GN-z11 is located in the direction of the constellation of Ursa Major.
We've taken a major step back in time, beyond what we'd ever expected to be able to do with Hubble. We see GN-z11 at a time when the universe was only three percent of its current age, explained principal investigator Pascal Oesch from Yale University.
The team includes scientists from Yale University, the Space Telescope Science Institute (STScI), and the University of California.
The new Hubble observations take astronomers into a realm that was once thought to be only reachable with NASA's upcoming James Webb Space Telescope which is scheduled to be operational in 2018.
This measurement provides strong evidence that some unusual and unexpectedly bright galaxies found earlier in Hubble images are really at extraordinary distances.
Astronomers measure large distances by determining the "redshift" of a galaxy.
This phenomenon is a result of the expansion of the universe; every distant object in the universe appears to be receding from us because its light is stretched to longer, redder wavelengths as it travels through expanding space to reach our telescopes.
The greater the redshift, the farther the galaxy.
"Our spectroscopic observations reveal the galaxy to be even farther away than we had originally thought, right at the distance limit of what Hubble can observe," said Gabriel Brammer of STScI, second author of the paper forthcoming in the Astrophysical Journal..
Before astronomers determined the distance for GN-z11, the most distant galaxy measured spectroscopically had a redshift of 8.68 (13.2 billion years in the past).
Now, the team has confirmed GN-z11 to be at a redshift of 11.1, nearly 200 million years closer to the Big Bang.
This is an extraordinary accomplishment for Hubble. It managed to beat all the previous distance records held for years by much larger ground-based telescopes," said investigator Pieter van Dokkum of Yale University. "This new record will likely stand until the launch of the James Webb Space Telescope."
The results reveal surprising new clues about the nature of the very early universe.
It's amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon," explained investigator Garth Illingworth of the University of California, Santa Cruz.
This new discovery shows that the Webb telescope will surely find many such young galaxies reaching back to when the first galaxies were forming," added Illingworth.
