The most distant known galaxy has been captured in a record-breaking image by the James Webb Space Telescope.
The galaxy, named JADES-GS-z14-0, is revealed as it was just 290 m years after the Big Bang, at the dawn of the universe. The telescope’s previous record holder was a galaxy seen 325m years after the Big Bang, which occurred nearly 14 billion years ago.
The newly observed galaxy is much brighter than expected, suggesting that the first generation of stars were either more luminous or formed much faster than conventional cosmological theories predicted.
“The universe in these early stages was different from what it is today,” said Dr Francesco D’Eugenio, from the University of Cambridge, one of the team behind the discovery. “Early galaxies – these are the most distant ones found, but there are others – appear to be brighter than expected from the models.”
Launching in 2021, the $10 billion James Webb Space Telescope can see further into the cosmos than any previous telescope. Due to the expansion of the universe, light from distant galaxies stretches to longer wavelengths as it moves, an effect known as redshift. In these galaxies, the effect is extreme, extending by a factor of 15, and even moving the ultraviolet light from the galaxies into infrared wavelengths where only the James Webb Space Telescope has the ability to see it.
These incredibly distant observations reveal the universe in its infant state and are already transforming scientists’ understanding of the early universe. An emerging theme is that galaxies and black holes appear to have grown much faster than expected.
Dr Stefano Carniani, of the Scuola Normale Superiore in Pisa, the lead author of the discovery paper, said: “JADES-GS-z14-0 is now becoming the archetype of this phenomenon. It’s amazing that the universe can make such a galaxy in only 300m years.”
This suggests that either the earliest stars were much more luminous than those seen today or that the galaxy was much more massive. “We’re not quite sure which one it is,” D’Eugenio said.
The unexpected brightness of these early galaxies means the telescope can make even more distant observations.
Prof Brant Robertson, from the University of California-Santa Cruz, said: “We could have detected this galaxy even though it was 10 times fainter, which means we could see other examples even earlier in the universe – probably in the first 200m years . The early universe has so much more to offer.”
