The Sun is very much a main sequence star, in the G-type category (G2V to be precise). It’s been fusing hydrogen for 4.6 ...

leading to a state of equilibrium between gravitational collapse and the energy released during fusion Key fact In a main sequence star, hydrogen nuclei fuse together to form helium nuclei.

The questions in this quiz are suitable for GCSE physics students studying the formation and life cycle of stars, main sequence stars and supernovae. If you struggled with the quiz, don't panic ...