Stellar Evolution

What is a nebula?

Images of nebulae in space with a question mark in the centre

What is the Sun?

Main Sequence

Main-sequence stars are fusing hydrogen into helium. These nuclear fusion take place deep in the cores of stars. Stars spend about 90% of their lives in this stage. Our Sun is about 5,000 million years into its 10,000 million-year main-sequence.

One of the fundamental forces in the Universe is gravity. It is the force that holds us on Earth. It also keeps planets in orbit around stars and stars in orbit around the centre of our galaxy.

Pair the Stages of a Star

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Though they shine for many thousands, and even millions of years, stars do not last for ever. They ignite, burn, and then run out of fuel and go out. 

Can you match the images of each stage of a star's existence to the correct description?


Order the Stages of a Star

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During their lives, stars undergo massive changes. What happens to them depends on how much mass they contain.

Can you put the stages that a low mass star and a high mass star will go through in the correct order on the diagram?