A black hole is a region in space where the pulling force of gravity is so strong that light is not able to escape.Because no light can escape, black holes are invisible. Some black holes are a result of dying stars.
If a star is orbiting a certain point in space, scientists can study the star's motion to find out if it is orbiting a black hole.When a black hole and a star are orbiting close together, high-energy light is produced. Scientific instruments can see this high-energy light.
How Big Are Black Holes?
There are three main types of black holes.
The smallest ones are known as primordial black holes. This type of black hole is as small as a single atom but with the mass of a large mountain.
The medium-sized black holes is called "stellar." The mass of a stellar black hole can be up to 20 times greater than the mass of the sun. Dozens of stellar mass black holes may exist within the Milky Way galaxy.
The largest black holes are called "supermassive." These black holes have masses greater than 1 million suns combined.Every large galaxy contains a supermassive black hole at its center. The supermassive black hole at the center of the Milky Way galaxy is called Sagittarius A.
Will the Sun Ever Turn Into a Black Hole?
The sun does not have enough mass to collapse into a black hole. In billions of years, when the sun is at the end of its life, it will become a red giant star. Then, when it has used the last of its fuel, it will throw off its outer layers and turn into a glowing ring of gas called a planetary nebula. Finally, all that will be left of the sun is a cooling white dwarf star.
