The 'hungry demons' roam the galaxy

Several hundred giant black holes can suck everything left from the early stages of the universe flying in our galaxy, according to a new study.

The picture illustrates a black hole 600 light years from Earth and 10 times the mass of the sun.Photo: hawaii.edu.

A black hole, or black hole, is an area in space that has such a gravitational force that no form of matter, including light, escapes from its boundary. The matter that wants to escape the black hole must have a escape velocity greater than the speed of light in vacuum. This ability cannot happen in the framework of relativity, whereby the speed of light in vacuum is the maximum achievable speed limit of all forms of matter. Many people liken black holes to greedy demons, because the amount of matter they can swallow is endless.

Scientists believe that previously "clumsy" black holes hid in the center of small galaxies, after several billion years, small galaxies collided and merged, forming large galaxies like So the big galaxy often has many black holes, some think they are fixed, but many astronomers claim they move.

A recent study by the Harvard-Smithsonian Center for Astrophysics (USA) shows that several hundred black holes have been created during galactic formation. 'Those black holes are the legacy of the galaxy's past. You can treat astronomers like archaeologists. They studied those legacies to better understand the history of the galaxy as well as the history of black hole formation in the early dawn of the universe , 'said Avi Loeb, a member of the research team.

Loeb and colleagues built a simulation model to predict the status of black holes. The model shows that they are wandering around and "hiding" inside the constellations. It seems that the earth will not become a prey of any black hole, because the nearest black hole is a few thousand light years from Earth.

Astronomers are keen to determine the location of black holes they can provide information about the process of forming galaxies.

The illustration of the process of black hole swallowing a star.Due to the tremendous attraction of the black hole, matter escapes the star and forms an arc of dust.A high amount of energy is released from the star's poles.Photo: space.com.

At the early stage of the universe, when two small galaxies (with a black hole in the center) collided, black holes could snap together to form a new black hole. The model shows that, when two galaxies merge, black holes can be pushed towards the edge of the new galaxy.

Galaxies today can be made up of hundreds of small galaxies, so the galaxy can contain up to several hundred black holes. Each black hole has a mass of 1,000-100,000 times the sun. However, their location is not easy, because they are invisible objects. Scientists only detect the existence of black holes due to the interaction between their gravitational field and the surrounding space.

Another sign can help us locate black holes. When the black hole escapes the small galaxy, it will drag into a cluster. Only stars near the black hole will be pulled away, so the cluster will be relatively dense. They are so small that if viewed from a distance, people would think it was a single star. Therefore, astronomers must use many tricks to distinguish them, such as splitting the light from the star cluster into 7 component colors to identify each star in the cluster.

'Star clusters near black holes are like lighthouse lights near dangerous sea reefs. Without such stars, we won't be able to detect black holes , ' explained Ryan O'Leary, a member of the research team.

The number of "lethargic" black holes in the galaxy depends on the number of small galaxies that make it up and how the galaxies merged. find new knowledge about the galaxy.