Our closest neighbor, Proxima Centauri, shines brightly in this Hubble image. Just one-eighth the mass of the Sun, Proxima Centauri is a red dwarf.

Most stars are main sequence stars that fuse hydrogen to form helium in their cores - including our sun.

Researchers believe 70 percent of all stars are born in clusters. Astrophysicists are looking to high-mass stars in faraway clusters for clues to the origins of life.

Extended syllabus content: The life cycle of stars If you are studying the Extended syllabus, you will also need to know about the formation and life cycle of stars in the section below.