Main sequence
What Main sequence means in Physics A-Level, as defined for AQA, OCR.
Definitions of Main sequence
Exam boards and our study guides word this term in slightly different ways. Learn the version your board uses.
Check what you remember
Read the wording for your board, then hide it and explain Main sequence in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
A diagonal band from top left (high luminosity, high temperature) to bottom right (low luminosity, low temperature), containing stars fusing hydrogen in their cores.
A band running diagonally from top left to bottom right on the HR diagram, near the centre of which the Sun is located.
A diagonal band from hot, luminous stars to cool, dim ones, containing stars that fuse hydrogen in their cores.
The region where a star spends most of its life fusing hydrogen, at roughly 5700 K and absolute magnitude +5.
Topics that use Main sequence
- The Hertzsprung-Russell (HR) diagram (A-level only) (AQA A-Level)
- Stars (OCR A-Level)
Related terms
- HR diagram
- White dwarf
- White dwarfs
- absolute magnitude
- Black hole
- Chandrasekhar limit
- Electron degeneracy pressure
- Giants and supergiants
Using Main sequence in the exam
Check the command word and mark scheme for your exact question. After comparing your explanation with the reference, use the term in an answer on the linked topic. This practice does not predict an exam mark.
Practise Physics questions
Create a free account to answer exam-style questions on this topic and get feedback on your answers.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge