Astronomers have located the farthest galaxy ever measured in the universe, more than 13 billion light-years away from the Earth.
An international team of astronomers, led by Yale University and the University of California-Santa Cruz, have lately discovered an extremely bright blue galaxy some 13.1 billion years in the past, when the universe was only five percent of its present age, according to a study published online in Astrophysical Journal Letters on May 5.
To measure its exact distance from the Earth, researchers have used the powerful MOSFIRE instrument on the W.M. Keck Observatory’s 10-meter telescope in Hawaii.
The galaxy, EGS-zs8-1, was first identified due to its special colors in pictures taken by NASA’s Hubble and Spitzer space telescopes, and is one of the most luminous and massive objects in the early universe.
“It has already built more than 15 percent of the mass of our own Milky Way today,” said Pascal Oesch, a Yale astronomer and lead author of the study. “But it had only 670 million years to do so. The universe was still very young then.”
Age and distance are interwoven in any discussion of the universe. The images of distant galaxies, taken via today’s advanced telescopes, are what actually those galaxies looked like billions of years ago depending on their distance from the Earth.
“Every confirmation adds another piece to the puzzle of how the first generations of galaxies formed in the early universe,” said Pieter van Dokkum, the Sol Goldman Family Professor of Astronomy and chair of Yale’s Department of Astronomy, the second author of the study. “Only the largest telescopes are powerful enough to reach to these large distances.”
According to researchers, measuring galaxies at extreme distances and characterizing their properties will be a major goal of astronomy over the next decade.
“Our current observations indicate that it will be very easy to measure accurate distances to these distant galaxies in the future with the James Webb Space Telescope,” said co-author Garth Illingworth of the University of California-Santa Cruz. “The result of JWST’s upcoming measurements will provide a much more complete picture of the formation of galaxies at the cosmic dawn.”
According to the Big Bang theory, the prevailing cosmological model, about 13.8 billion years ago, the whole universe was in an extremely high-density state and then expanded, forming the universe we know today.