Astronomers may have uncovered how galaxies change their shape

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

Ever for the reason that Hubble Sequence, that classifies galaxy morphologies, was invented in 1926, astronomers have been refining our understanding of galaxy evolution and morphology as our expertise 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 clean and featureless, generally known as elliptical and lenticular (formed like a lens).

Revealed as we speak 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 rationale 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 number of galaxies packed collectively,” Dr. Pfeffer mentioned.

“The spiral arms on galaxies are so fragile, and as you go to greater 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 giant elliptical galaxy within the aftermath.”

The research utilized the highly effective EAGLE simulations to investigate 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 might classify nearly 20,000 galaxies per minute, compressing what would usually 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 research 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 varied items of analysis in galactic evolution, to know the morphology-density relation for the primary time.

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