As is probably expected, the James Webb Space Telescope has redefined what it means to probe the universe.

The high-end telescope has offered astronomers around the globe a new tool to peer back in time to when some of the first galaxies were birthed.

The images of deep space the telescope has delivered are beyond breathtaking, but their scientific value is even grater.

Now, astronomers say they likely identified a galaxy that formed not long –in cosmological scales — after the Big Bang.

CEERS-93316, a Galaxy, far, far away

A galaxy candidate that formed approximately 250 million years after the Big Bang is included in the first data set from the James Webb Space Telescope (JWST).

The study has been submitted to the Monthly Notices of the Royal Astronomical Society. If the candidate galaxy is confirmed, it would be the farthest galaxy observed at only 250 million years after the Big Bang.

The observation also includes an unprecedented redshift with a value of z = 16.7. The redshift is part of what is known as the Doppler effect, which astronomers use to measure distances in the universe.

As JWST only started sending back data a few weeks ago, this finding is extremely intriguing since it shows its power. CEERS stands for Cosmic Evolution Early Release Science Survey and was specifically created for imaging with JWST.

“The last few weeks have been surreal, watching JWST break all the records that have been held for a long time with Hubble,” says Dr. Rebecca Bowler, Ernest Rutherford Fellow at the University of Manchester and co-author of the study “Finding a candidate for galaxy z = 16.7 (redshift) is an amazing feeling. It was not something we expected from the first data.”

Researchers in this study refer to several previous studies that have measured objects down to redshift z = 10 using observations from the ground and from Hubble and Spitzer telescopes.

“It is amazing to have found such a distant galaxy candidate with Webb given that this is only the first data set,” says Callum Donnan, a Ph.D. student at the University of Edinburgh and lead author of the study, quoted by Universe Today. “It’s important to note that to be sure of the redshift, the galaxy will need follow-up observations using spectroscopy. That’s why we refer to it as a galaxy candidate.”

NIRCam (Near Infrared Camera), the key imager of JWST, determined CEERS-93316 is not a low-mass star or an unobstructed active galactic nucleus. Cosmologists aim to learn what is happening in galaxies so young, so soon after the Big Bang, since CEERS-93316 might be only 250 million years old.

“After the Big Bang, the Universe went through a period called the dark ages, during which no stars were born,” explains Dr. Bowler. “The observations of this galaxy push the observations back to a time when we think the first galaxies that existed were forming.

There are still many open questions about how and when the first stars and galaxies formed in the early Universe, as cosmologists have already found more galaxies than predicted by computer simulations.

Bowler explains that JWST is capable of detecting galaxies with redshifts greater than 20, which means less than 200 million years after the Big Bang.

CERRS 93316 provides hope that these galaxies may exist, despite the high difficulty of finding them.

“The most distant phenomenon observed is the cosmic microwave background (CMB), which is the ‘glow’ of the Big Bang,” explains Donnan. “The light from the CMB comes from about 400,000 years after the Big Bang and has been observed by various instruments over the years, most notably the Planck satellite that launched in 2009. Webb won’t be able to see until then, but he is able to probe the early stages of galaxy formation.

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Source: Curiosmos