Webb’s telescope – here is a picture of some of the most distant galaxies. GLASS-z12 goes for a record
A few days after the start of its mission, the James Webb Telescope took an image of the galaxy cluster Abell 2744 (also known as Pandora), in order to capture in this image two galaxies located much further away, claiming to be the farthest ever observed. One of them existed 450 million years after the Big Bang, while the other, called GLASS-z12, emitted light already 350 million years after the beginning of the universe – so it traveled towards the Earth for as long as 13.5 billion years. These revelations are revealed in two scientific papers that have just been published in the Astrophysical Journal Letters.
It is possible that GLASS-z12 will become the farthest and oldest galaxy known to mankind. This turn of events will be determined by Webb’s spectroscopic studies, which will allow for a detailed calculation of the object’s distance. At the moment, scientists have estimated it based on the redshift analysis, which in the case of the aforementioned galaxy ranges from as much as 12.2 to 12.4 (the latter has a redshift of 10.4 to 10.6). This is how both objects look like – GLASS-z12 has been described with the number 2:
The record for the farthest galaxy is officially still held by GN-z11, spotted in 2016 by the Hubble and Keck telescopes, which existed only 400 million years after the Big Bang. However, her days on the throne seem numbered; in the near future, HD1, discovered in April (redshift – 13.27; it would have to exist 324 million years after the beginning of creation), as well as numerous galaxies spotted by the Webb telescope, will be subjected to spectroscopic studies. At least one scientific paper is waiting for a review, the authors of which claim that the galaxy they observed had a redshift of as much as 16.
Scientists who discovered GLASS-z12 reveal that it is a relatively small object (its diameter is only a few percent of the diameter of the Milky Way) that surprises with its unexpectedly high brightness; it appears that in the early universe, many galaxies shone much brighter than researchers had previously believed. As if that wasn’t enough, GLASS-z12 and other of the oldest galaxies were probably already forming around 100 million after the Big Bang – also much earlier than scientists thought.
Paola Santini, one of the authors of the work on newly discovered galaxies, sums up the whole situation in this way:
These observations make your head explode. We are starting a whole new chapter in astronomy. It’s like doing an archaeological dig and suddenly you find a lost city and something you didn’t know existed. It’s amazing.