The most distant galaxy in the universe.. "James Webb" surprises continue
The James Webb Space Telescope has detected the most distant galaxy ever discovered, which formed in the early ages of the universe, just 320 million years after the Big Bang, according to two studies whose results were published Tuesday.
It is well known that the more distant galaxies are, i.e. young ones in turn, the more difficult it is to detect them due to the weak optical signal emanating from them.
The first data recorded by the James Webb telescope, which has been in service since July 2022, has identified many galaxies whose light signals may be within the infrared range, which are wavelengths invisible to the human eye and whose observation allows diving into the depths of the distant past.
The NIRCam camera integrated with the telescope, thanks to its powerful ability to probe infrared radiation, along with spectral analysis that analyzes the light emanating from an object to determine its chemical elements, confirmed "unequivocally" the existence of four galaxies, all of which are located on the red side in the sky. The ends of the spectrum, that is, they are very far away.
The formation of these galaxies dates back to a period ranging between 300 million years and 500 million years after the Big Bang (which occurred 13.8 billion years ago), according to two studies published in the journal Nature Astronomy.
The age of the universe at that time was only 2% of its current age, in what is called the period of reionization, that is, when the universe re-ignited somewhat and began to produce a huge number of stars, after a period called the Dark Ages.
Stéphane Charlot of the Astrophysical Institute in Paris, one of the study's authors, explained to AFP that the most distant galaxies spotted by the James Webb telescope, called JADES-GS-z13-0, formed "320 million years after the Big Bang". Its light is the farthest ever observed by astronomers.
Technical achievement
The space telescope also confirmed the existence of the galaxy GM-z11, which dates back to 450 million years after the Big Bang and was first discovered by the Hubble telescope.
The four galaxies observed by the James Webb telescope have a very low mass, approximately 100 million solar masses, while the Milky Way, for example, has 1500 billion solar masses. But these galaxies are "very active in star formation, relative to their mass," according to the physicist.
Stars are forming there “at almost the same rate as in the Milky Way,” a speed that is “very surprising compared to this very early stage in the formation of the universe,” according to what this researcher at the French National Center for Scientific Research comments.
It also turns out, according to the researchers, that these galaxies are "very poor in metals", a finding that aligns with the standard model of cosmology: the closer we get to the origins of the universe, the less time stars have to form these complex particles.
And the astronomer at Yale University, Peter Van Dokkum, said in a comment attached to the study that these observations, which were monitored by the James Webb telescope, constitute a "technical achievement." He stressed that the telescope is expanding "almost every month" the frontiers of exploration, and probes the depths of the universe more and more with the passage of time.
Last February, the tool developed by the US Space Agency (NASA) monitored six galaxies that formed between 500 and 700 million years after the Big Bang, and it turned out that they are much larger than expected.
And if the existence of these galaxies is confirmed by spectral analysis, this may prompt a reconsideration of part of the theory of the formation of the universe.
Source: websites