The team of American and Dutch astronomers led by scientists from Yale University and the University of Calfornia-Santa Cruz, identified the galaxy originally based on its striking blue color in images of the Hubble and Spitzer space telescopes of NASA.
galaxy that EGS zs8-1 is called, is one of the brightest and most massive objects in the early universe. The exact distance from Earth, 13.1 billion light-years, was calculated using the powerful tool MOSFIRE of the 10-meter telescope at the Keck Observatory in Hawaii, according to the shift of the light.
Age and distance are inextricably linked in any discussion about the universe. The light that we see from our sun, is doing just eight minutes to reach us, and the light we see with our telescopes from distant galaxies, there have been billions of years to reach us, and we see these galaxies than as well as billions of years ago looked like.
The galaxy EGS zs8-1 looks as if it is a 100 million years old, and there are new stars formed at a very fast pace, almost 80 times faster than in our galaxy.
“The galaxy has already built more than 15 percent of the mass of our galaxy,” said Pascal Oesch, an astronomer at Yale and lead author of the study on the Yale website. “But it was only 670 million years to do that. The universe was still very young.”
Re-ionization
So far only a handful of galaxies from the very early universe calculated the distance accurately. “Any confirmation (from a distance) adds another piece to the puzzle of how the first generations of galaxies originated in the early universe,” said Pieter van Dokkum, the leader of the department of astronomy at Yale and the author of the second study. “Only the largest telescopes are powerful enough to handle these large distances.”
The observations show EGS zs8-1 at the time that the universe underwent a major change: the hydrogen between galaxies was changing from a neutral state to an ionized state. “It seems that the young stars in early galaxies like EGS zs8-1, the main aanstuurders were for this transition, which is called re-ionization,” said Rychard Bouwens of Leiden Observatory, one of the co-authors of the study.
Taken together, throw the observations of the new Keck Observatory and the Hubble and Spitzer telescope also new questions. They confirm that there existed early in the history of the universe, massive galaxies, but they also show that these galaxies had very different physical properties compared to what we see today around us. Astronomers now have strong evidence that the remarkable colors of early galaxies, as seen on the images of Spitzer, find their origin in the rapid formation of massive, young stars, who responded to the primordial gas in the galaxies.
Exciting discoveries
The MOSFIRE-instrument Keck telescope allows astronomers to study several galaxies at the same time efficiently. The survey of galaxies at extreme distances and the characterization of their properties, an important goal will be the next decade, the researchers said.
The observations underline the exciting discoveries that will be possible if NASA her James Webb Space Telescope will launch in 2018, the researchers say. Not only will enable these observations that still further be in the past, but he will also be able to analyze the light of EGS-zs8-1 and astronomers to provide details about the properties of the gases in the galaxy.
“Our current observations show that it will be very easy in the future with the James Webb Space Telescope to accurately measure the distance to distant galaxies,” said co-author Garth Illingworth of the University of California-Santa Cruz. “The results of the measurements of JWST will have a much more complete picture of the formation of galaxies in the early universe.”
The study on EGD zs8-1 published in The Astrophysical Journal Letters.
The galaxy was first identified in images from Hubble and the Spitzer Space Telescope (Photo : NASA / ESA / P.Oesch / I.Momcheva / 3D HST and HUDF09 / XDF)
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