The universe in which we live is constantly changing, moving and every day brings new discoveries. So, scientists have discovered that relatively “recently” by cosmic standards, our Milky Way galaxy has consumed a small satellite galaxy.
The black hole located in the center of our galaxy collided with a similar black hole, which was the nucleus of another galaxy. This happened 2 million years ago and caused a “super fireworks”, thanks to which active star formation processes continue in the center of the Milky Way.
Here astronomers discovered three massive clusters with hundreds of young stars, and there are practically no old stars in this area. This is also confirmed by the Fermi Bubbles, which are intense emissions of high-energy particles. They spread over 290 thousand light-years, diverging away from the center of the Milky Way disk.
Scientists suggest that the Milky Way galaxy 13 billion years ago began to converge and absorb a small satellite galaxy. The black hole, the core of the galaxy, whose mass was approximately 10 thousand Suns, flew in interstellar space until 10 million years ago it collided with our larger black hole, which led to the mass death of old stars and the formation of new ones.
But this is not the only global cataclysm. According to calculations, the Milky Way expects another large-scale collision. This time we are drawing closer to the Andromeda Nebula. The merger is expected in four billion years, and in two more we will become one bright galaxy. Then the night sky observed from the Earth will be a truly spectacular sight, if, of course, someone will admire it.
For the first time, astronomers were able to make out the Andromeda Nebula about 1 thousand years ago, and now this galaxy is viewed as a small fuzzy object. But once this object, which today is not at all impressive in its appearance, will be able to absorb the Sun and the Earth.
The fact that these two galaxies are moving towards each other has been found out for a long time. Until recently, they tried to understand whether the Andromeda Nebula would pass by or if it would fly straight towards us. Using the modern capabilities of the Hubble telescope, scientists simulated future processes and calculated the current speed of movement of galaxies. Computer visualization clearly showed how the Milky Way and Andromeda will unite over time, forming a single bright galaxy in the shape of an ellipse.
In this case, the collisions of stars should not occur, since the distances between them are simply huge. However, scientists are confident that the location of the solar system in this process will irreversibly change. What consequences this will have for the Earth is not yet clear.
A small galaxy-satellite of Andromeda called the Triangle Galaxy will also be involved in the merger.
Recall that now the Milky Way is like an elongated disk with a diameter of about 100,000 lights. years and a thickness of about 1000 lights. years. There are from 250 to 400 billion stars in our galaxy.
In the center of the rotating disk, in the constellation Sagittarius, there is a thickening - the core of the galaxy. It is supposed to be a huge black hole, around which several thousand other relatively small black holes rotate.
The solar system is closer to the edge of our galaxy, so here the distance between the stars is thousands of times greater than in the central part. The sun, like other stars, revolves around the galactic center. One revolution takes place 200 million years. It turns out that the Earth during its life was able to fly around our galaxy in a circle 30 times.
What will the Milky Way look like after merging with Andromeda, how will the rules and physical laws change? This is an open question, a reliable answer to which we will never know.