Why is the Galaxy Not Sucked By Black Hole at its Center?

If there is a black hole at the center of every galaxy, why are the galaxies not inhaled by the black hole? This question may ring in your mind. But, let's find out a simple explanation.

We tend to think of black holes as a kind of cosmic "vacuum cleaner," which constantly sucks all the material around it. While it is true that if you put an object into a black hole, you will never get the object back, but the black hole is actually very bad in pulling material close to it.

Keep in mind that black holes attract objects around them with gravity, just as the planets in our solar system are attracted to the Sun's gravity so that they are in stable orbits. Most of the stars in the galaxy are in a stable orbit around a black hole, so the galaxy will not be inhaled by a black hole.

In the scale of the distance of the galaxy, the gravitational effects of black holes are no different from ordinary stars with the same mass. All objects that have the right speed will remain in a stable orbit around a more massive object (actually they are actually orbiting the center of mass, or a row, which for galaxies, these rows are usually right with the center of the galaxy).

The gravity of a black hole in the center of the galaxy is too weak to affect the stars in the related galaxy. In fact, most stars in a particular galaxy may not feel the existence of a black hole in the center of the galaxy.

For example, the black hole at the center of the Milky Way galaxy (known as Sagittarius A), has only 4 million times the mass of the Sun with its gravitational influence sphere of only 9.7 light years, while the Sagittarius A distance to our solar system is about 26,000 years light.

In other words, to be attracted to the black hole at the center of the galaxy, an object must be within the scope of the gravitational influence of its black hole. However, if it is so far away from the position of Earth and our solar system, then we will be safe in this galaxy.