Fiducia TogetherSpace physics
The solar system, the life cycle of stars and the evidence for the Big Bang.
Please note: This page explains a word or a process in education. It is general information about the system, the law and the guidance in England — not advice about your child, your school or your exam. If a decision is going against you, get advice from one of the free services we link to before you agree to anything or miss a deadline. If you are revising, check your own exam board's specification: boards word things differently and yours is the one that marks you.
What it is
The solar system consists of the Sun, planets, dwarf planets, moons and smaller bodies. Stars form from clouds of dust and gas pulled together by gravity.
Where it applies
GCSE physics, and it is not on all combined science specifications.
How it works
A star's life depends on its mass. A star like the Sun becomes a red giant, then a white dwarf. A much more massive star becomes a red supergiant, explodes as a supernova, and leaves a neutron star or a black hole.
Red-shift of light from distant galaxies, and the fact that more distant galaxies are receding faster, is the evidence for an expanding universe and the Big Bang.
How to use it in your work
Learn both star life cycles as sequences and say which mass range each applies to.
For red-shift, say what is observed and what it implies — observation then conclusion.
A stable star is in equilibrium between inward gravity and outward pressure from fusion. That sentence answers several questions.
Where to get help
Your teacher, your board's specification for the depth required at your tier, and Bitesize for the diagrams.
Revise this with a song
These are ours. We write revision songs because a lot of people remember a tune when they cannot remember a page, and because revising out loud in the kitchen beats staring at a highlighter.
- The Physics Song The GCSE physics specification, set to music.
Where to read more
Last reviewed 2026-08-28 by Fiducia Together · Next review due 2027-08-28
Please note: This page explains a word or a process in education. It is general information about the system, the law and the guidance in England — not advice about your child, your school or your exam. If a decision is going against you, get advice from one of the free services we link to before you agree to anything or miss a deadline. If you are revising, check your own exam board's specification: boards word things differently and yours is the one that marks you.