|Image above: A supernova blows up in space. Credit: NASA|
|Image above: After becoming a red giant, a small star will become a white dwarf and a large star will become a supernova. Credit: NASA|
A star is born out of a cloud of gases and dust.
|Main Sequence Star
Next, it is a "baby" protostar. A star later becomes a main sequence star. Most of the star's life is in this stage.
After billions of years, the star will become a red giant. The outer layer of the star gets bigger. But it shrinks on the inside. Now, the star is called a red giant.
Inside, the star gets hotter and thicker. There is iron inside. The iron soaks up the star's energy. Finally, it lets go of the energy. This is the death of the star. It ends when the star blows up. This explosion is what we call a supernova. It can light up the sky for weeks. It can get very, very hot.
After a star blows up, there are leftovers. The leftovers can be very heavy. The inside core that is left over is called a neutron star.
If the star was more than eight times bigger than our Sun, the leftovers will be a black hole. A black hole is the end of a very large star. It has a lot of strong gravity. A black hole does not give off light, so we cannot see them. We know that black holes are out there by using X rays.