Astronomers use the James Webb Space Telescope have discovered what they believe to be three of the earliest galaxies in our universe, actively forming when the cosmos was only 400 million to 600 million years old.
In the JWST images, this galactic trio appears as faint red blobs feeding on nearby helium and hydrogen. For millions of years, it is these elements that sustain such galaxies as they grow, helping to form them into the familiar ellipses and spirals we see throughout space. cosmos.
“You could say that these are the first ‘direct’ images of formation of galaxies we’ve ever seen,” study lead author Kasper Elm Heintzan astrophysicist at the Cosmic Dawn Center (DAWN) in Denmark, said in a rack. ‘While James Webb has previously shown us early galaxies in later stages of evolution, here we are witnessing their birth, and thus the construction of the universe’s first galaxies.’
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Our universe existed about 400,000 years after the Big Bang darkness introduced. This happened next room enough had cooled from its previously chaotic and scorching self to allow for neutral hydrogen atoms that covered the cosmos with an opaque primordial mist. That fog cleared about 1 billion years after the Big Bang, when light emerged from the first generation stars flooded the universe. Recent research has shown that dwarf galaxies that formed during the first few hundred million years of the universe are very dense surprisingly plentiful punch to drive this fog-lightening process.
“This is the process we see the beginnings of in our observations,” co-author Darach Watson said in the university’s statement. “These galaxies are like sparkling islands in a sea of otherwise neutral, opaque gas,” Heintz added. NASA statement.
The legacy of a sparkling cosmic trio
JWST’s powerful infrared eye was able to capture how light from the three observed galaxies was absorbed by large, dense reservoirs of neutral hydrogen gas surrounding them. This result also showed that gas was collecting in and feeding the galaxies themselves. In fact, there is so much gas present that the galaxies have not yet produced their first stars. For stars to form, some parts of such primordial gas must coalesce into extremely dense regions, which then fuels the formation of stellar bodies. It would probably have taken millions of years for the first generation of stars to be born in these galaxies.
Astronomers do not yet know how gas is distributed between the centers of galaxies, which are also located supermassive black holes, as well as in galactic suburbs. Future observations could not only help solve that puzzle, but they could also reveal whether the gas reservoirs of these galaxies are composed entirely of primordial hydrogen, or are already sprinkled with heavier elements.
“It’s a process we’ll continue to explore until we can hopefully put even more pieces of the puzzle together,” says co-author Gabriel Brammer of DAWN.
He noted that this discovery provides proof JWST extends beyond its primary mission goals. “Images and data from these distant galaxies were impossible to obtain before Webb,” he said. “Plus, we had a good idea of what we were going to find when we first glimpsed the data — we were almost making discoveries by eye.”
The findings are described in a paper published May 23 in the journal Science.