The Family of Stars
We see thousands of stars in the night sky. Each one is unique. When you look at individual stars, some look bright and close while others seem dim and distant. A few, like Betelgeuse and Sirius, are so bright that you can make out their colors.
Stars shine because they convert matter to energy and radiate it as light. If we graph them by temperature and brightness, most fall into a band called the main sequence.
Remnants of Stars
Most stars spend their lives fusing hydrogen into atoms of helium, carbon, and oxygen. Those elements are recycled into clouds of gas and dust in the interstellar medium and become the seed material for new generations of stars and planets. Massive stars blast elements out in supernova explosions. A star like the Sun gradually sheds its outer layers to space. The Little Ghost planetary nebula (NGC 6369) was once part of a sunlike star.