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A Monster Black Hole Quietly Going About Its Business Discovered Nearby : ScienceAlert

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Black holes are among the most formidable and mysterious objects in the known Universe. These gravitational giants form when massive stars undergo a gravitational collapse at the end of their lives and shed their outer layers in a massive explosion (a supernova).

Meanwhile, the stellar remnant becomes so dense that the curvature of space-time becomes infinite around it, and gravity is so intense that nothing (not even light) can escape its surface. This makes it impossible to observe objects using conventional optical telescopes, which examine them in visible light.

As a result, astronomers typically look for black holes at unseen wavelengths or by observing their effects on objects around them.

A team of astronomers led by the University of Alabama Huntsville (UAH) recently observed a black hole in our cosmic backyard, after consulting Gaia Data Release 3 (DR3). As they describe in their work, this monstrous black hole is roughly twelve times the mass of our Sun and is located about 1,550 light-years from Earth.

Due to its mass and relative proximity, this black hole offers opportunities for astrophysicists.

The study was led by Pei-Ling Chan Endowment Chair at UAH’s Department of Physics. It was led by Sukanya Chakrabarti. Astronomers from the Carnegie Institute for Science, the Rochester Institute of Technology, the SETI Institute Carl Sagan Center, UC Santa Cruz, UC Berkeley, the University of Notre Dame, Wisconsin-Milwaukee, Hawaii, and Yale Observatories participated.

The paper describing its findings was recently published online and is currently under review. Astrophysical Journal.

Black holes are of particular interest to astronomers, as they offer opportunities to study the laws of physics in the most extreme conditions. In some cases, they also play a vital role in galaxy formation and evolution, such as the supermassive black holes (SMBH) found at the centers of most large galaxies.

However, there are still unresolved questions about the role non-interacting black holes play in galactic evolution. These binary systems consist of a black hole and a star, where the black hole does not pull material from its stellar companion. Dr. Chakrabari said in the UAH press release:

“It is not yet clear how these non-interacting black holes affect galactic dynamics in the Milky Way. If they are in number, they can affect the formation and internal dynamics of our galaxy. We have searched for objects that have been reported to have large companion masses. However, their luminosity can be attributed to a single visible star. Therefore, thinking that the companion is dark You have good reason to.”

To find the black hole, Dr. Chakrabarti and his team analyzed data from Gaia DR3, which contains information on nearly 200,000 binary stars observed by the European Space Agency’s (ESA) Gaia Observatory. The team followed sources of interest by resorting to spectrographic measurements from other telescopes such as the Lick Observatory’s Automatic Planet Finder, the Giant Magellan Telescope (GMT) and the WM Keck Observatory in Hawaii.

These measurements showed a main sequence star subject to a strong gravitational force. Dr. As Chakrabari explains:

“The black hole’s gravitational pull on the visible Sun-like star can be determined from these spectroscopic measurements, which give us the line-of-sight velocity due to a Doppler shift. By analyzing the line-of-sight velocities of the visible stars – and this visible star is similar to our Sun – the black hole’s companion is how big it is, its rotation period. And we can infer how eccentric the orbit is. These spectroscopic measurements independently confirmed the Gaia solution as well. This binary system consists of a visible star orbiting a very large object.”

Interacting black holes are generally easier to observe in visible light because they are in tighter orbits and pull material from their stellar companions. This material forms a torus-shaped accretion disk around the black hole, accelerating to relativistic speeds (close to the speed of light), becoming extremely energetic and emitting X-ray radiation.

Since non-interacting black holes have wider orbits and do not form these disks, their existence must be understood by analyzing the movements of the visible star. Dr. Chakrabarti said:

“Most black holes in binary systems are in X-ray binaries – in other words, they are bright in X-rays due to some interaction with the black hole, usually the black hole swallowing the other star. This deep gravitational potential from the other star falls into the well, we can see the X-rays. In this case, “We’re looking at a monster black hole, but it’s on a long orbit of 185 days, or about half a year. It’s quite far from the visible star and isn’t making any progress toward it.”

Dr. The techniques used by Chakrabarti and colleagues could lead to the discovery of many more non-interactive systems.

According to current estimates, there may be a million visible stars with massive black hole companions in our galaxy. While this represents a small fraction of the stellar population (~100 billion stars), the Gaia Observatory’s precise measurements narrowed this search. Gaia so far stars, galaxies,

Further studies of this population will allow astronomers to learn more about this binary system population and the way black holes form. Dr. As Chakrabarti summarizes:

“There are several different paths currently being proposed by theorists, but non-interacting black holes around bright stars are a very new type of population. So it will probably take us some time to understand their demographics and how they form and how these channels form, interacting, converging black holes that are better known. holes are different from the population – or if they are similar.”

This article was originally published by Universe Today. Read the original article.