A black hole is a place in space. Its gravity is so strong. Even light cannot get out. A black hole is a lot of matter. It is squeezed into a very small space. Black holes are invisible. That is because no light comes out of them.

Black holes do not roam around space eating stars and planets. From far away, a black hole pulls on things the same as any other object with the same mass. If the Sun turned into a black hole of the same mass, Earth would not be swallowed.

Gas that falls toward a black hole gets very hot. It glows. We can see the glow. We cannot see the black hole.

Black holes grow bigger when they take in more stuff. They can get bigger by crashing into stars and other black holes.

The edge of a black hole is the event horizon. Nothing can come back out once it crosses it. The event horizon is not a hard surface like the ground. At the center of a black hole there may be a point called the singularity. It is where everything that falls in ends up.

When a big star runs out of fuel, it collapses. Some of these stars become black holes.

Black holes come in different sizes. The biggest are called supermassive black holes. Some have as much mass as millions of Suns. Our Milky Way galaxy has a giant black hole at its center.

Black holes do not last forever. They very slowly shrink and evaporate.

In 2019, scientists showed the first picture of a black hole. It was in a galaxy called Messier 87. The picture shows a bright ring. In the middle is a dark spot. In 2022, scientists showed the first picture of the black hole at the center of our galaxy.

Words to know

• singularity: center point
• evaporate: shrink away
• supermassive: biggest black holes