Researchers “Possibility of a very early globular cluster, about 500 million years after the birth of the universe”
A globular cluster of distant galaxies, including the oldest known very early star, was captured by the James Webb Space Telescope (JWST), researchers at the University of Toronto in Canada announced on the 29th (local time).
As a result of capturing and analyzing signals from globular clusters with JWST, the researchers explain that it may contain early stars that were shining about 500 million years after the birth of the universe, that is, 13 billion years ago or earlier.
This is much older than our Sun formed about 4.6 billion years ago.
According to the University of Toronto in Canada and the American Astronomical Society (AAS), researchers from the University’s Dunlab Institute of Astronomy and Astrophysics, including Dr. Ramiya Moula and Dr.
This is the result of an initial analysis of the ‘Webb’s First Deep Field’ image released to the public by NASA on July 11 this year.
The researchers explain that it may be information about some of the earliest galaxies that appeared in the universe.
The research team comprehensively analyzed the data collected by the ‘Near Infrared Camera’ (NIRCam) and ‘Near Infrared Imager and Slitless Spectroscopy’ (NIRISS) devices published in JWST and the old data of the Hubble Space Telescope (HST) in the past. I came to a conclusion.
“The purpose of the JWST is to discover the first stars and the first galaxies, and to help us understand what constitutes a source of complexity in the universe, such as chemical elements and the basic units that create life,” said Moula. did.
“This discovery, made in the web’s first deep field, already provides detailed information about the earliest stages of star formation,” he said.
The researchers focused on a specific part of the first deep-field images on the web.
This is the visible part of the galaxy, which the researchers have decided to call ‘sparkler’.
This galaxy is about 9 billion light years away.
When observing with JWST, the identity of the yellow and red glowing dots (sparkle) visible around it was not clear.
Researchers believe that these sparkles may be in the form of young star clusters actively forming stars 3 billion years after the start of the universe, the Big Bang, or globular clusters of very old stars.
A globular cluster is a dense cluster of tens to tens of millions of stars formed from the early days of galaxies, and contains information that can be a clue to the early formation and growth of galaxies.
There are about 150 globular clusters in our galaxy, but it is unknown exactly when they formed.
Analyzing 12 of the points around the ‘Sparkler Galaxy’, the researchers explain that five of them appear to belong to the oldest known globular clusters.
This is the first time that very distant globular clusters have been used to estimate the ages of the earliest stars in distant galaxies.
“It was an incredible moment to look at the first images from JWST and find old globular clusters around distant galaxies,” said Dr. Ayr. “It allowed us to better understand their physical properties, such as how old they are and how many stars there are.”
However, the estimate of ‘about 500 million years after the Big Bang, 13 billion years ago or earlier’ comes from an early analysis, so it is difficult to say with great certainty.
The paper containing the results of this study was published on the 29th in ‘The Astrophysical Journal Letters’, an academic journal issued by AAS.
/yunhap news