Keck Telescopes Confirm Existence of Faintest, Furthest Galaxy 13 Billion Light Years Away
Scientist from UC Davis discovered have detected and confirmed the existence of the faintest early-universe galaxy that is presumed to be as it was about 13 billion years ago.
The discovery, published in the Astrophysical Journal Letters, was made possible using DEIMOS (Deep Imaging and Multi-Object Spectrograph) instrument mounted on the 10-meter telescope at the W.M. Keck Observatory on the summit of Mauna Kea, Hawaii and was powered by gravitational lensing.
Sir Albert Einstein first predicted the phenomena behind gravitational lensing. According to the researchers, the ability of gravity to bend the path light made it possible for a distant galaxy to be magnified through the lens created by another object between the viewer and the observed object.
For their discovery, researchers detected the object behind the MACS2129.4-0741, a massive cluster of galaxies big enough to create three different images of the object. The objects were known to belong to same galaxy due to their similar spectra.
"This galaxy is exciting because the team infers a very low stellar mass, or only 1 percent of 1 percent of the Milky Way galaxy," said Marc Kassis, staff astronomer at the Keck Observatory, in a statement.
"It's a very, very small galaxy and at such a great distance, it's a clue in answering one of the fundamental questions astronomy is trying to understand: What is causing the hydrogen gas at the very beginning of the universe to go from neutral to ionized about 13 billion years ago? That's when stars turned on and matter became more complex," added Kassis in the same report.
Researchers believe that the galaxy that they discovered is at the edge of reionization epoch, the period when galactic hydrogen gases shifted from neutrality to ionization.
According to the report from Tech Times, the discovered galaxy was first captured by Hubble and Spitzer space telescopes late last year, but it is only now that the scientists have applied gravitational lensing in their search that made it more easy to be observed.