A billion-light-year-wide 'bubble of galaxies’ discovered

Astronomers have discovered the first „bubble of galaxies,” an almost unimaginably massive cosmic structure sitting in our galactic backyard thought to be a fossilized remnant after the Big Bang.

The bubble spans a billion light-years, making it 10,000 times wider than the Milky Way galaxy.

Yet this giant bubble, invisible to the naked eye, is a relatively distant 820 million light-years from our home galaxy, in what astronomers call the nearby universe.

The bubble can be thought of as „a spherical shell with a heart,” Daniel Pomerat, an astrophysicist at France’s Atomic Energy Commission, told AFP.

Inside that heart is the Boots Supercluster of galaxies, surrounded by a vast void sometimes called „The Great Nothing.”

The shell already contains several interstellar superclusters known to science, including a massive structure called the Sloan Great Wall.

Pomaret said of the bubble’s discovery, which is described in research he co-authored. The Astrophysical Journal This week, it was „part of a very long scientific process.”

This confirms a phenomenon described in 1970 by American cosmologist and future physics Nobel laureate Jim Peebles.

He hypothesized that in the early universe—then a shell of hot plasma—the noise of gravity and radiation produced sound waves called baryon acoustic oscillations (BAOs).

As the sound waves rippled through the plasma, they formed bubbles.

About 380,000 years after the Big Bang the process stopped as the universe cooled and froze the shape of the bubbles.

Bubbles grew larger as the universe expanded, just like other fossil remains after the Big Bang.

Astronomers previously detected signals of BAOs in 2005 while looking at data from nearby galaxies.

But the newly discovered bubble is, according to the researchers, the first known single baryon acoustic oscillation.

’unexpected’

Astronomers called their bubble Holilana — „the one that sent out murmurs of awareness” — taking the name from a Hawaiian formation chant.

The name comes from the study’s lead author, University of Hawaii astronomer Brent Tully.

The bubble was discovered by accident as part of Tully’s mission to search for new catalogs of galaxies.

„It was something unexpected,” Pomaret said.

The bubble „is so large that it extends to the edges of the region of the sky we analyzed,” Tully said in a statement.

The pair enlisted the help of Australian cosmologist and BAO expert Cullen Howlett, who „mathematically determined the spherical structure to match the data provided,” Pomerate said.

This allowed the trio to visualize the three-dimensional shape of Holilana and the position of the constellations within it.

This may be the first time, but soon more bubbles may be seen throughout the universe.

Europe’s Euclid Space Telescope, launched in July, will take a broader view of the universe and trap some more bubbles.

Massive radio telescopes called the Square Kilometer Array, built in South Africa and Australia, could provide a new picture of galaxies from a Southern Hemisphere perspective, Pomaret said.