Astronomers discover Milky Way-like barred spiral galaxy in early Universe using Webb

Using NASA's powerful science observatory, the James Webb Space Telescope, an international team, including a UC Riverside astronomer, has discovered the most distant barred spiral galaxy similar to the Milky Way that has been observed to date.

Until now it was believed that Milky Way-like barred spiral galaxies could not be observed before the universe, estimated to be 13.8 billion years old, reached half of its current age.

The barred spiral galaxy observed in the early universe is ceers-2112. It has a galactic bar - a structure made of stars within galaxies - which are very rare.

"This galaxy, named ceers-2112, formed soon after the Big Bang. Finding ceers-2112 shows that galaxies in the early universe could be as ordered as the Milky Way. This is surprising because galaxies were much more chaotic in the early universe and very few had similar structures to the Milky Way," said coauthor de la Vega, a postdoctoral researcher in the Department of Physics and Astronomy.

According to him, galactic bars are thought to form in spiral galaxies with stars that rotate in an ordered fashion, the way they do in our home galaxy.

The researchers expect that this discovery will change at least two aspects of astronomy:

"First, theoretical models of galaxy formation and evolution will need to account for some galaxies becoming stable enough to host bars very early in the universe's history,” de la Vega said. These models may need to adjust how much dark matter makes up galaxies in the early universe, as dark matter is believed to affect the rate at which bars form.

Second, the discovery of the Milky Way-like barred spiral galaxy in the early Universe demonstrates that structures like bars can be detected when the universe was very young. This is important because galaxies in the distant past were smaller than they are now, which makes finding bars harder. 

More details can be found here.