Astronomers may have uncovered how galaxies change their shape

Researchers could have answered a decades-old query about galaxy evolution, leveraging the facility of synthetic intelligence (AI) to speed up their analysis.

Ever because the Hubble Sequence, that classifies galaxy morphologies, was invented in 1926, astronomers have been refining our understanding of galaxy evolution and morphology as our know-how advances.

By the Seventies, researchers had confirmed that lone galaxies are typically spiral-shaped, and people present in clusters of galaxies have been prone to be easy and featureless, often known as elliptical and lenticular (formed like a lens).

Printed in the present day within the journal Month-to-month Notices of the Royal Astronomical Society, new analysis led by astronomers on the Worldwide Centre for Radio Astronomy Analysis (ICRAR) could have uncovered the explanation for these variations in shapes.

Lead creator Dr. Joel Pfeffer from The College of Western Australia node of ICRAR, mentioned the analysis explains the ‘morphology-density relation’—the place clustered galaxies seem smoother and extra featureless than their solo counterparts.

“We have found there are a couple of various things occurring once we get a lot of galaxies packed collectively,” Dr. Pfeffer mentioned.

“The spiral arms on galaxies are so fragile, and as you go to increased densities within the galaxy clusters, spiral galaxies begin to lose their gasoline. This lack of gasoline causes them to ‘drop’ their spiral arms, reworking right into a lenticular form. One other trigger is galaxy mergers, which might see two or extra spiral galaxies crashing collectively to type one massive elliptical galaxy within the aftermath.”

The examine utilized the highly effective EAGLE simulations to research a bunch of galaxies intimately, utilizing an AI algorithm to categorise galaxies by their form.

The neural network-based algorithm was educated by ICRAR Ph.D. candidate Mitchell Cavanagh and may classify virtually 20,000 galaxies per minute, compressing what would sometimes take weeks into one hour.

The simulations carefully match what has been noticed within the universe, giving researchers the boldness to make use of the simulation results to interpret observations of galaxy clusters

The examine additionally recognized a number of lenticular galaxies exterior of the high-density areas the place they’re anticipated, with the modeling suggesting they have been created by the merging of two galaxies.

Dr. Pfeffer mentioned the work brings collectively numerous items of analysis in galactic evolution, to grasp the morphology-density relation for the primary time.

“There’s been a lot of strategies over time,” he mentioned. “However that is the primary work to essentially put all of items of the puzzle collectively.”