A black hole is a space where gravity pulls so much that even light is unable to come out. The gravity is so strong due to the squeezing of matter into a small space. When a star is dying, this can happen.
Because no light can come out, no black holes can be seen by people. It’s invisible. Space telescopes can help find black holes with special tools. The special tools can see how stars act differently from other stars that are very close to black holes.
How Big Are Black Holes?
There may be big or small black holes. Scientists believe that the smallest black holes are as small as a single atom. These black holes are very small, but they have a big mountain’s mass. Mass is the amount of matter, or “stuff,” in an object. Another type of black hole is called “Stella” Its mass can be up to 20 times as much as the sun’s mass. There may be many, many black holes of stellar mass in the galaxy of Earth. The galaxy of Earth is called the Milky Way.
How Do Black Holes Form?
Scientists think that the smallest black holes formed when the universe began. Stellar black holes are made when a very big star’s center falls or collapses on itself. It causes a supernova when this happens. A supernova is an explosive star that blows part of the star into space. Scientists believe that at the same time as the galaxy they are in, supermassive black holes have been made.
If Black Holes Are “Black,”
How Do Scientists Know They Are There?It is not possible to see a black hole because strong gravity pulls all the light into the black hole center. But scientists can see how the strong gravity around the black hole affects the stars and gas. Scientists can study stars to find out whether they are flying around a black hole or orbiting it. When a black hole and a star are close together, high-energy light is created. It is not possible to see this kind of light with human eyes. To see the high-energy light, scientists use satellites and telescopes in space.
Could a Black Hole Destroy Earth?
Black holes do not eat stars, moons and planets in space. Earth will not fall into a black hole because there is no black hole close enough to Earth’s solar system to do that. Even if a black hole took the same mass as the sun, Earth would still not fall into it. The sun would have the same gravity as the black hole. Earth and the other planets would be orbiting the black hole as they now orbit the sun. The sun will never become a black hole. The sun is not a star large enough to make a black hole.
How Is NASA Studying Black Holes?
NASA uses space traveling satellites and telescopes to learn more about black holes. These spacecraft assist scientists in answering universe questions.