Webb snaps Milky Way-like galaxies taking shape long, long ago.

PhysOrg looks back (via the James Webb Space Telescope) to when the universe was a quarter of its current age, and has been able to see young galaxies stretching out into shapes like our own Milky Way:

In a Hubble image, one galaxy, EGS-23205, is little more than a disk-shaped smudge, but in the corresponding JWST image taken this past summer, it’s a beautiful spiral galaxy with a clear stellar bar.

“I took one look at these data, and I said, ‘We are dropping everything else!'” said Shardha Jogee, professor of astronomy at The University of Texas at Austin. “The bars hardly visible in Hubble data just popped out in the JWST image, showing the tremendous power of JWST to see the underlying structure in galaxies,” she said, describing data from the Cosmic Evolution Early Release Science Survey (CEERS), led by UT Austin professor, Steven Finkelstein.

Bars play an important role in galaxy evolution by funneling gas into the central regions, boosting star formation.

“Bars solve the supply chain problem in galaxies,” Jogee said. “Just like we need to bring raw material from the harbor to inland factories that make new products, a bar powerfully transports gas into the central region where the gas is rapidly converted into new stars at a rate typically 10 to 100 times faster than in the rest of the galaxy.”

Bars also help to grow supermassive black holes in the centers of galaxies by channeling the gas part of the way.

“This discovery of early bars means galaxy evolution models now have a new pathway via bars to accelerate the production of new stars at early epochs,” Jogee said.

And the very existence of these early bars challenges theoretical models as they need to get the galaxy physics right in order to predict the correct abundance of bars. The team will be testing different models in their next papers.

You can read more of the findings here, in The Astrophysical Journal.