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. As the Sun starts to set and the sky darkens, the stars seem to appear.