Early galaxies seen by James Webb Telescope offer insight into early universe

Nov. 18 (UPI) -- The James Webb Space Telescope (JWST) has captured images of two of the farthest galaxies seen to date.

The two galaxies are located several billion light years behind the giant galaxy cluster Abell 2744. Data indicates the two galaxies would have had to have been formed approximately 450 million and 350 million years after the Big Bang.

Two research papers analyzing Webb's data have been published in the Astrophysical Journal Letters, one lead by Marco Castellano, of the National Institute for Astrophysics in Rome, Italy, and one lead by Rohan Naidu, of the Harvard-Smithsonian Center for Astrophysics in Massachusetts.

"With Webb we were amazed to find the most distant starlight that anyone has ever seen, just days after Webb released its first data," Naidu.

The initial findings come from two Early Release Science Programs within the Webb initiation, the Grism Lens-Amplified Survey from Space (GLASS) and the Cosmic Evolution Early Release Science Survey (CEERS).

The new data suggests that galaxies in the early universe were much brighter than originally thought, meaning Webb may be able to gather significantly more data about the early universe.

"We've nailed something incredibly fascinating. These galaxies would have had to have started coming together maybe just 100 million years after the Big Bang. Nobody expected that the dark ages would have ended so early," said Garth Illingworth, a Naidu/Oesch team member from the University of California at Santa Cruz.

Scientists theorize that the brightness could be caused by population III stars, the extremely hot, bright stars that formed shortly after the Big Bang. Such stars were composed of only primordial hydrogen and helium, and would have burned much brighter and more quickly than the stars we see in the local universe, where population III stars don't exist.

"These observations just make your head explode. This is a whole new chapter in astronomy. It's like an archeological dig, and suddenly you find a lost city or something you didn't know about. It's just staggering," said Paola Santini, a co-author of Castellano's GLASS-JWST paper.

"Everything we see is new. Webb is showing us that there's a very rich universe beyond what we imagined," said Tommaso Tree of the University of California at Los Angeles, principal investigator on one of the Webb programs.