“Mysterious” blue bubbles in the universe reveal a new type of star system

Published on 05/07/2022 22:08

The cluster of young blue stars is seen here using the Hubble Space Telescope’s Advanced Camera for Surveys – (Credit: Michael Jones/Reproduction)

Discovered by a group of Astronomy scientists from the University of Arizona has revealed a new class of star systems never seen before in the universe. Formed by blue bubbles, the researchers found five star systems isolated from any parent galaxy, consisting only of young blue stars, distributed in an irregular pattern.

The star clusters found near Virgo galaxies are the size of small dwarf galaxies and were captured during observations by the Hubble Telescopes, the Array and the Very Large Telescopes. Scientists have called the discovered star systems “objects”, because they are not exactly like that galaxies Although it looks so.

The researchers realized they were encountering a new class of star system when they noticed the stark differences between clusters with a common galaxy. First, the five systems are isolated, located 300,000 light-years from any galaxy, challenging the common process of creating such a cluster.

Another unusual point is the very low level of atomic hydrogen gas recorded in the space inhabited by the systems, which is unusual in places where there are young stars and also where new stars are forming – and this is the case with these groups.

The lack of gas may indicate a galaxy with a greater presence of old stars, called red and dead. However, scientists encountered the unlikely: there are no red stars in the solar system.

Michael Jones, lead author of the study, and postdoctoral fellow presents: “Stars born in red are less dense, and therefore live longer than blue stars, which burn quickly and die young, so old red stars are usually the last surviving stars. life”. at the University of Arizona.

“And the red stars died because they had no gas left to form new stars. So what we see is that these blue stars are basically like an oasis in the desert,” Jones explains. Somehow, even with a little gas, new stars are created and no red stars are recorded.

“Theft” in the universe? The star system may have been created by extracting gas from galaxies

With the features identified, scientists began to try to find hypotheses for the formation of star systems. The research noted a large presence of metals, which are any element heavier than helium. To get these “raw materials,” the researchers say the mass would need to be “stolen” from a large galaxy.

“This tells us that these star systems formed from gas taken from a large galaxy, because the way minerals are built is through many of the repeating star-forming rings, and you only get that in a large galaxy.” Jones paints.

This gas extraction process may be via a collision – called tidal stripping – when two large galaxies pass each other and leaves gas and stars behind.

The other way to “steal” the gas is through a process called ram compression – which is what most scientists believe. “It’s like you’re belly-jumping into the pool,” Jones said. “When the belly of a galaxy falls into a mass filled with hot gas, its gas is pushed out from behind it. That’s the mechanism we think we’re seeing here to create these objects,” he adds.

Researchers also believe that the blue bubbles could be the beginning of a major puzzle in astronomy: the transformation of spiral galaxies into elliptical galaxies. After the “belly falls into the pond”, blue bubbles form that will develop into an elliptical galaxy.

The study was presented by Jones and David Sand, a professor at the University of Arizona, at the 240th meeting of the American Astronomical Society on June 15. The research began after researchers were asked for a “gas cloud map” created by the Netherlands Institute for Radio Astronomy, which indicated a list of possible locations for new galaxies.

The researchers celebrated that, rather than galaxies, they were able to record a new class of star system. “It’s a lesson for the unexpected,” Jones said. “When you look for things, you won’t necessarily find what you’re looking for, but you might find something else very interesting.”