Astronomers have managed to see for the first time dwarf galaxies with giant black holes that are about to merge

For the first time, astronomers have discovered a pair of dwarf galaxies with giant black holes in their path of collision. In fact, it’s not one pair, but two, they note in a study accepted for publication in The Astrophysical Journal.

The first pair of merging dwarf galaxies is in a group known as Abell 133, about 760 million light-years from Earth, and the other is in the Abell 1758S group of galaxies, about 3.2 billion light-years away.

These observations and future research are expected to uncover some of the secrets of the early universe, a time when these pairs of dwarf galaxies with colliding black holes were much more common.

Dwarf galaxies, weaker light signals

“Astronomers have found many examples of black hole collisions in large galaxies that are relatively close, but their searches in dwarf galaxies are much more difficult and have so far been unsuccessful,” said University of Alabama astrophysicist Marko Micic, who led the study. .

What makes these observations difficult is that the smaller size of these pairs of galaxies makes their weaker light signals more difficult to observe. These galaxies contain stars with a combined mass of about 3 billion times that of the sun, and there are approximately 60 billion suns in our Milky Way.

To make the discovery, the researchers combined data from several telescopes: results from NASA’s Chandra X-ray Observatory, results from the Wide Field Infrared Explorer (WISE), and results from the Canadian-French-Hawaiian Observatory. The X-ray data were the most important, as they found the strongest signals emitted by black hole pairs.

Hints about our own galaxy

“By using these systems as models of the early universe, we can gain insight into the first galaxies, their black holes, and the star formation that caused the collisions,” says astrophysicist Olivia Holmes of the University of Alabama.

Over billions of years, these smaller colliding galaxies are believed to have coalesced to form the largest galaxies (including the Milky Way) that dominate the universe today. Researchers call them our “galactic ancestors.”

We might even get an idea of ​​how our own galaxy came into being and evolved to where it is today. They note that there are several inconsistencies in our home galaxy that have yet to be resolved.

Now that astronomers have their eyes on these active galactic nuclei, or AGNs, they will be able to get more details from them as our telescope technology and image analysis continue to improve.

“Following observations of these two systems will allow us to study processes that are critical to understanding galaxies and their young black holes,” says astrophysicist Jimmy Irwin of the University of Alabama.

EE (Scientific Alert, Astrophysical Journal)