How Do Some Supergalaxies Form? A New Study Reveals

Scientists examined how some huge objects referred to as supergalaxies form in the universe. They have observed a massive galaxy cluster called the Spiderweb Galaxy.

The Spiderweb Galaxy is also known as MRC 1138-262 that is about 10.6 billion lightyears away from the planet Earth. It is an irregular galaxy with a redshift of 2.156. In the study, the researchers discovered that it was formed in a different way than they previously thought.

They found that Spiderweb Galaxy was growing by slurping a cold molecular gas. Bjorn Emonts from the Centre for Astrobiology in Spain and the lead author of the study said that this galaxy is different from what they see in the nearby universe, where galaxies in clusters grow by cannibalizing other galaxies. He further explained that in this cluster, a giant galaxy is growing by feeding on the soup of cold gas in which it is submerged.

Nina Hatch, an astronomer from the University of Nottingham in the U.K. and was not involved in the study, said that extremely massive galaxies are seen in the young universe. However, their presence is puzzling because people do not yet understand how they became so massive quickly. She asked, "How do they get enough fuel to form stars so rapidly?"

Naturally, supergalaxies or huge galaxies shaped from smaller galaxies that moved closer together until they merged due to gravitational attraction. On the other hand, in the earliest days of the universe, this might not be wherein there were not enough stars and baby galaxies around.

Meanwhile, in the recent study, the researchers discovered that the massive Spiderweb Galaxy condensed directly from the cloud of gas. The team identified the visibility of carbon monoxide (CO) gas in the distant galaxy, which suggests the presence of hydrogen. They also found that the hydrogen cloud was huge, and the gas was unexpectedly cold about 200 degrees Celsius, according to Science Alert.

Matthew Lehnert, one of researchers from the Astrophysics Institute of Paris, described the find as surprising. He said that they would have expected a lot of collapsing galaxies, which would have heated the gas. For that reason, they thought that the carbon monoxide would be much more difficult to detect.

The new study is significant in understanding how supergalaxies are born. They also aid the scientists in comprehending why the universe looks the way it does.