Andromeda will collide with Milky Way after 4,5 billion years.

  

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Andromeda will collide with Milky Way after 4,5 billion years. 

Black holes are the most stable objects in the universe, but they are also moving. The fact is that the black holes are interacting with other objects, and the thing that can move them is another black hole. This thing is happening right now because the supermassive black holes of the Andromeda and Milky Way galaxies are at impact course, and those black holes will impact in the distant future. 

There are three confirmed types of black holes. The Earth (or planetary mass back holes), stellar-mass and supermassive black holes but there is a possibility that there are more black hole types than those three. The quantum-size or atomic size black holes and the hyper massive black holes are waiting for their founder. 

And as in the article below this text tells there are two parts in black holes the event horizon, and singularity which is the form of material of that thing. In black holes, the material is so dense that the entire star has collapsed to the size of an atom. But sometimes writers including myself are using singularity as the area in the event horizon. The term event horizon means the point, where escaping velocity is reaching the speed of the light. 

So what is inside the black hole? We don't know, and maybe we ever know that thing. But the black hole itself is so interesting thing, that it fascinates many ways. There is a theory that if the planet-mass black hole is forming in the atmosphere of the star, it can just start to hover above the star resting on its jet, which can move the entire star across the universe. 

Epsilon Indi and black holes

But how the planet-size black hole is forming? The fact is that there is a theory that the radio bursts from the neutron stars or the energy load from super hot stars will turn the planet into a black hole. And if that black hole would have an ability to hover resting on its jets, it can be used as the engine for some futuristic spacecraft. 

The reason for that theory is that the star named Epsilon Indi travels in the universe at a very high speed. And because that star is a bright X-ray target, that thing means that there is possible a small black hole in that solar system. So Epsilon Indi caused the idea that the super civilizations could transport their solar system through the universe by creating a black hole in the atmosphere of their home star. That thing would transport their solar system in the direction where they want. 

Confirmation of the black hole of the Epsilon Indi bases only on the X-ray observations of that star and its extremely fast proper motion. But we can remember another X-ray target, the Cygnus X-1 what uncovered one of the first known stellar-mass black holes in the universe. 

When the small size black hole is impacting the atmosphere of some planet, it can also start to hover resting on its jets, and the X-ray burst, what hits the planet can turn it into the black hole because it will pump it with energy. But there is an idea that this kind of planet-mass black hole would pump the energy to some stars and turn them into quasi-stars. The fact is that we don't know any quasi stars yet.  

Sources: 

Andromeda-Milky way collision:  https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_collision

The Black Hole article:  https://www.deccanherald.com/science-and-environment/black-holes-dont-move-around-sucking-objects-iucaa-chief-908134.html

Epsilon Indi:  https://en.wikipedia.org/wiki/Epsilon_Indi

Cygnus X-1:  https://en.wikipedia.org/wiki/Cygnus_X-1