The James Webb Space Telescope The four most distant galaxies ever observed have been discovered, including one that formed just 320 million years after the Big Bang when the universe was still in its infancy, new research said Tuesday.
The Webb Telescope has made a flurry of scientific discoveries since it went live last year, peering into more distant regions of the universe than ever before – meaning it’s looking back in time.
By the time light from the most distant galaxy reaches Earth, it has been stretched by the expansion of the universe and shifted into the infrared region of the light spectrum.
The Webb Telescope’s NIRCam instrument has an unprecedented ability to detect this infrared light, allowing it to quickly identify a never-before-seen range of galaxies—some of which could change astronomers’ understanding of the early universe.
inside Two studies Published in Nature Astronomy journal, astronomers revealed that they had “ambiguously identified” four of the most distant galaxies ever observed.
The galaxy dates from 300 to 500 million years after the Big Bang, 13 billion years ago, when the universe was only two percent of its current age.
That means galaxies have what’s called a “regeneration age,” a period when the first stars are believed to have formed. The epoch was directly followed by the Cosmic Dark Ages by the Big Bang.
Stephen Charlotte, a researcher at the Institute of Astrophysics in Paris and co-author of the two new studies, told AFP that the most distant galaxy – called JADES-GS-z13-0 – formed 320 million years after the Big Bang.
This is the largest distance observed by astronomers, he said.
The Webb Telescope confirmed the existence of JADES-GS-z10-0, which was observed 450 million years after the Big Bang and earlier by the Hubble Space Telescope.
All four galaxies are “very low in mass,” weighing in at about a hundred million solar masses, Charlotte said. According to some estimates, the Milky Way weighs 1.5 trillion solar masses.
But galaxies are “very active in star formation relative to their mass,” Charlotte said.
These stars were forming “at about the same rate as the Milky Way,” a pace that was “surprising for such an early universe,” he added.
Galaxies were also “Metals are very poor,” she added.
This is consistent with the standard model of cosmology, science’s best understanding of how the universe works, which says that closer to the Big Bang, there would be less time for such metals to form.
A technical tour de force
However, the discovery in February of six massive galaxies 500-700 million years after the Big Bang has some astronomers questioning the Standard Model.
These galaxies, also observed by the Webb Telescope, are larger than what was thought possible shortly after the birth of the universe – if confirmed, the Standard Model may need to be updated.
Peter van Dokum, an astronomer at Yale University who was not involved in the latest study, Confirmation welcome One of four newly discovered distant galaxies as a “technological tour de force”.
“The frontier is moving almost every month,” van Dokkum Comment inside the natureadding that there was now “only about 300 million years of undiscovered history of the universe between this galaxy and the Big Bang”.
The Webb Telescope has observed possible galaxies close to the Big Bang, but they have not yet been confirmed, he said.
© Agence France-Presse