As starlight travels through Earth's atmosphere it makes some stars look like they are twinkling. Stars live for billions of years. After a star explodes it is called a supernova . The light it gives off when it explodes is brighter than a million stars. A black hole is the collapse of a supernova under the force of its own gravity.
Nothing nearby can escape from the black hole .
The Sun is eight light minutes from us. The next star is four light years away. Some stars are billions of light years away. The stars are always in the sky, even during the day. We can't see them because the sun is too bright.