The Five Hundred Meter Aperture Spherical Radio Telescope (FAST) has discovered an atomic cloud 20 times larger than the Milky Way: its dimension is 2 million light years in diameter and is the largest ever discovered in space.
This cloud was found in Stephan’s Fiftha group of galaxies located regarding 10,000 light years from Earth, in the constellation of Pegasus.
Xu Cong, lead author of this research and who leads the team from the National Astronomical Observatories of China, explained to the Hong Kong newspaper South China Morning Post that astronomers wanted to use the sensitivity of FAST to better understand how galaxies interacted with each other when they came together. for the first time as a group.
To achieve your goal, searched for hydrogen atoms in the area around Stephan’s Quintetas these particles emit a unique “signature” that can reveal information regarding events that happened long ago.
How did they find this atomic cloud?
The discovery was made possible following FAST, located in China’s Guizhou province, targeted the cluster of galaxies, recognized in recent days following the James Webb Space Telescope imaged Stephan’s Quintet.
Galaxies collide in Stephan’s Quintet, pulling and stretching each other in a gravitational dance. In the mid-infrared view here, see how Webb pierces through dust, giving new insight into how interactions like these may have driven galaxy evolution in the early universe. pic.twitter.com/3P15LMCCOH
— NASA Webb Telescope (@NASAWebb) July 12, 2022
Xu expressed: “It was a challenging task due to the weak signals from the atoms and the large area observed, but FAST’s well-tuned receiver and giant dish, which is the size of 30 football fields, made it possible.”.
The researchers were surprised to see a gigantic gaseous structure like this, being located in turn unusually far from the center of the quintet of galaxies where hydrogen atoms tend to accumulate.
The academic sowed mystery to the study: “We wonder why it still exists, since the atomic gas with low density should have been destroyed by ultraviolet radiation in the cosmic background, according to current theories.”.