Australia-led astronomy project throws the story of the origin of the Milky Way into suspicion


Astronomers are rethinking the story of our origin, following our discoveries about the behavior of galaxies that resemble the Milky Way.

The first detailed cross-section of another galaxy, UGC10738, resembles our galaxy, but shows that the Milky Way actually evolved gradually, instead of a violent collision due to an anomalous accident.

A separate disk similar to those in the Milky Way proves that such a structure is a product of more peaceful change than previous theories predicted. Those theories argued that they were formed from rare collisions with smaller galaxies.

The University of Sydney made an unexpected discovery with a team led by Nicholas Scott and Jesse van de Sande of Australia’s ARC Center of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D).

“Our observations are that the thin and thick disk of the Milky Way was not a result of a huge mashup, but a kind of” default “pathway for galaxy formation and evolution,” Scott said. It was.

“From these results, I think a galaxy with a particular structure and characteristics of the Milky Way can be described as a” normal “galaxy. “

The team was able to see a cross-section of the structure of the galaxy because the galaxy was angled “straight”.

“It’s a bit like distinguishing between short and tall people,” Scott said. “It’s impossible to do it from overhead, but it’s relatively easy to do from the side.”

The findings of the Australian-led astronomy team, published in The Astrophysical Journal Letters on May 25, are significant.

The article’s co-author, Professor Ken Freeman of the Australian National University, said the discovery was It prompted an important reassessment of how the Milky Way has evolved over billions of years.

“I was always worried that the Milky Way was not a typical spiral galaxy. Now I see that the formation of the Milky Way is pretty typical of how other disc galaxies were assembled,” Freeman said. Told.

Lisa Kewley, director of ASTRO3D, said it would help answer some questions about the evolution of the galaxy.

“This work shows how the Milky Way fits into a much larger puzzle of how spiral galaxies were formed over 13 billion years of space time,” Curie said.