Chinese scientists discover clues to understanding process of star formation at edge of Milky Way

Researchers from the School of Physics and Astronomy at China West Normal University have discovered two young star clusters at the edge of the Milky Way. The objects, named after Mount Emei in southwest China, are located approximately 45,000 light-years from Earth. This was reported by CCTV+, a partner of TV BRICS.

The clusters are estimated to be just 10 million years old, which is very young by cosmic standards. They formed within so-called high-velocity clouds – massive streams of gas that originated outside the galaxy and penetrated its outer regions.

For a long time, scientists believed that stars could not form within high-velocity clouds. Astronomers observed only gas within them and found no signs of star formation. However, new observations have revealed a different story.

It turned out that one of the fast-moving gas clouds collided with the outer edge of the Milky Way’s disc. As a result of the violent collision, the gas was compressed so strongly that it triggered the process of star formation. This is precisely how the two young clusters came into being.

This finding is the first clear evidence that stars can form within high-velocity clouds.

"Contrary to traditional understanding, this proves that star formation is not confined to the interiors of galaxies but can also occur in their outer fringes, effectively identifying a 'blood supply system' that sustains the star life cycle of the galaxies," said He Zhihong, an associate professor from the School of Physics and Astronomy at China West Normal University.

The significance of the discovery extends beyond a single example of star formation. It helps us better understand the evolution of the Milky Way – the galaxy is not a closed system but constantly draws in fresh gas from its surroundings, including high-speed clouds. When this material collides with the galactic disc, the raw material necessary for the formation of new stars is released.