Astronomers may have found some of the very earliest stars thanks to James Webb
Astronomers made a new discovery in the very first full-color image released from the James Webb Space Telescope.
The discovery is indicative not only of the new insight James Webb is yet to reveal but also of the treasure trove of information stored in every image it has already released.
The first full-color James Webb image, revealed by President Joe Biden on July 11, shows a vast network of galaxies and peers billions of years into the past. Within that network, astronomers believe they have identified the most distant globular clusters ever identified, as per a BBC report.
Meet the Sparkler Galaxy
Globular clusters are dense star collections whose origins aren't fully understood. The Milky Way is home to roughly 100 of these compact clusters that are known to have fewer heavy chemical elements that are associated with newer stars such as our Sun. Still, scientists are unsure how and when they came to be.
Now, the new James Webb image, SMACS 0723, shows a very distant globular cluster magnified by gravitational lensing. Astronomers from the University of Toronto found the cluster and named it "the Sparkler Galaxy" because it's surrounded by small yellow-red dots that look like sparks. They detailed their findings in a paper in The Astrophysical Journal Letters.
Those "sparks" wouldn't have been visible to us if it weren't for the power of James Webb. Thanks to the gravitational lensing in the SMACS 0723 image, the Sparkler Galaxy also appears three times due to strange distorting effects. Gravitational lenses not only magnify distant objects but also distort them and have been known to create "mirror" images of distant galaxies.
The University of Toronto team originally thought that the "sparks" might actually be separate objects far past or in front of the Sparkler Galaxy. However, the fact that all three versions of the Sparkler Galaxy show the same dots strongly suggests they are connected.
James Webb peers into the ancient past
The astronomers believe the sparkles are globular clusters like the ones seen around the Milky Way. Crucially, though, we're seeing clusters that are much, much older and were created at a much earlier time in the history of the Universe.
The image we see of the Sparkler Galaxy, in fact, shows what it looked like nine billion years ago, roughly 4.5 billion years after the Big Bang. The University of Toronto team explained that the galaxy cluster is redder than expected, meaning it is older than they would have thought, given how early it is in the Universe, relatively speaking.
That means they believe the globular sparkles formed only a few hundred million years after the Big Bang. They may even contain some of the very first stars to have formed in the Universe. In an interview with the BBC, one of the astronomers, Dr. Lamiya Mowla from Toronto's Dunlap Institute for Astronomy & Astrophysics, said, "when we first opened the SMACS image, we too were searching for the furthest stuff, the farthest things. And then we literally got sidetracked by the shiniest, sparkly object."
There's nothing wrong, of course, with getting sidetracked when looking at the image of SMACS 0723 — the photograph is literally filled to the brim with tiny networks of worlds, all dating back to an ancient past much closer to the Big Bang. The truly incredible thing about that image is that we may never be able to fully analyze every tiny dot highlighted in immense detail, thanks to James Webb.