Distant galaxy seen for the first time
A team of international scientists has observed a distant galaxy that has never been glimpsed before, so remote that its light takes billions of years to reach the earth.
Spectacular images of the far-off galaxy were spied through the Hubble space telescope and confirmed by the Keck observatory in Hawaii.
The scientists revealed their findings during the annual meeting of the American Association for the Advancement of Science in Seattle (US).
It took 13 billion light-years for light from the galaxy to reach the earth, light that was first emitted from the galaxy when the universe was just 750 million years old, according to the scientists.
Faint
“The galaxy we have discovered is extremely faint, and verifying its distance has been an extraordinary challenging adventure,” explained astronomer Jean-Paul Kneib, of the California Institute of Technology and the Midi-Pyrenees observatory in France, the principal investigator who helped confirmed the sighting.
The location of the galaxy was plotted through a long exposure of the Abell 2218 cluster taken with the Hubble space telescope and confirmed with telescopes based at the Keck laboratory.
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“Our study has only been possible by pushing our current observatories to the limits of their capabilities” Jean-Paul Kneib, |
The galaxy was spotted with the help of so-called “gravitational lensing,” which is based on Albert Einstein’s theory of relativity.
Gravitational lensing works on the basis that light can be bent in predictable ways, this helps scientists to identify and locate far away objects and galaxies.
“Our study has only been possible by pushing our current observatories to the limits of their capabilities,” Kneib said.
“As we were searching for distant galaxies magnified by Abell 2218, we detected a pair of strikingly similar images whose arrangement and colour indicated a very distant object,” Kneib explained.
“The existence of two images of the same object indicated that the phenomenon of gravitational lensing was at work.”
According to the study, an intriguing property of the new galaxy is the apparent lack of the typically bright hydrogen emission seen in many distant objects, and an intense ultraviolet signal.