A team of international astronomers has discovered the first ‘bubble of galaxies’, an unimaginably massive cosmic structure a billion light-years in diameter that is believed to be a fossilized remnant of the immediate aftermath of the Big Bang.
The width of the bubble is 10,000 times the size of the Milky Way, according to the scientists who made the discovery. published Their findings this week.
“This massive bubble is a fossil from the time of the Big Bang 13 billion years ago when the universe formed,” team member Colan Howlett, from the University of Queensland’s School of Mathematics and Physics, said in comments posted on Thursday.
“We weren’t even looking for it, but the structure is so massive that it extended to the edges of the sector of sky that we were analyzing,” Howlett said in an interview published by the University of Queensland.
“It’s dwarfed by many of the largest known structures, like the Sloan Great Wall and Bootes, which are actually part of this bubble,” he said.
“What makes it even more incredible is that it’s located in our backyard,” he added.
The bubble is centered about 820 million light-years away from our galaxy, in what astronomers call the Near Universe.
This image posted on September 7, 2023 shows a 3D representation of the “bubble” galaxy, colored brown. The image shows the location of the Milky Way, with a small white dot outside the bubble on the right, in the midst of a white cloud [Frederic Durillon and Daniel Pomarede/Animea Studio/CEA/ AFP]
This discovery provides a clearer picture of the expansion rate of the universe, Howlett said, and the results could revolutionize cosmology.
“Our analysis indicates that this bubble is larger than expected, and that the universe has expanded more than originally expected,” he said.
“We are now one step away from bringing about such a significant change in the field of cosmology that the entire universe model may need to be re-evaluated.”
“The Great Thing”
Daniel Pomaridy, a member of the team and an astrophysicist at the French Atomic Energy Authority, said the galactic bubble can be thought of as a “spherical shell with a core”.
Within this core is the Potts supercluster of galaxies, which are surrounded by a vast void sometimes called the “Great Nothing”.
The crust contains many other giant clusters of galaxies already known to science, including the massive structure known as the Great Wall of Sloan.
Pomaridy said the discovery of the bubble, which is described in the paper he co-authored and published in The Astrophysical Journal this week, was “part of a very long scientific process.”
This discovery also confirms a phenomenon that was first described in 1970 by Canadian-American cosmologist – and future Nobel Prize winner in Physics – Jim Peebles.
He hypothesized that in the primordial universe – which was then a jumble of hot plasma – gravitational ripples and radiation created sound waves called baryon acoustic oscillations (BAOs).
When sound waves ripple through the plasma, they create bubbles.
About 380,000 years after the Big Bang, the process stopped when the universe cooled, freezing the shape of the bubbles. The bubbles then grew larger as the universe expanded, similar to other fossilized remnants from some time after the Big Bang.
Astronomers previously detected signals of BAOs in 2005 when looking at data from nearby galaxies. But the newly discovered bubble is the first single sonic oscillation of a baryon, according to the researchers.
The astronomers named their bubble Ho’oleilana — meaning “puffs of awakening sent” — taking the name from a Hawaiian creation chant.
The name came from the study’s lead author, Brent Tully, an astronomer at the University of Hawaii.
