Life Cycle of a Star like the Sun
Physics: Edexcel IGCSE, topic 8.2.1
Life Cycle of a Star like the Sun
The life cycle of a star depends on its size. All stars begin their life cycle in the same way. Gravity pulls nebulae together to form a protostar. This protostar turns into a main sequence star. If a star is a similar size as the Sun, its lifecycle is:
Main sequence
- In a main sequence star, hydrogen nuclei are fused together to form helium.
- This releases energy as heat and light.
Red giant
- Eventually all the hydrogen fuel runs out.
- The star then cools and expands, becoming a red giant.
- The star then starts to fuse together helium nuclei to release energy.
White dwarf
- As the helium fuel runs out, the outward forces reduce in size and the star collapses inwards.
- This causes its temperature to increase.
- A white dwarf is formed, which is the hot core of the star.
Black dwarf
- When the star completely cools, the star becomes a black dwarf.
- A black dwarf doesn’t emit (send out) any light or heat.
Test yourself on Life Cycle of a Star like the Sun
Life Cycle of a Star like the Sun
Which of these is a part of a small star's life cycle?
What does a main sequence star become when the hydrogen fuel runs out?