Stellar process
Main-Sequence Evolution
The long, stable middle age of a star, during which it fuses hydrogen into helium in its core. This is where stars spend most of their lives — the Sun for roughly ten billion years — and a star's mass fixes where it sits along the main sequence, how brightly it burns, and how long it lasts.
Highlights
- ›Core hydrogen burning — the longest phase of a star's life
Stars, stages & concepts
Across stellar astrophysics
Knowledge connections
- Associated withPre-Main-Sequence Evolution
- Associated withThe Hertzsprung–Russell Diagram
- Associated withThe Proton–Proton Chain
- Associated withThe Sun
- Associated withThe Red-Giant Branch
- Associated withThe Proton–Proton Chain
- Associated withThe CNO Cycle
- Associated withThe Hertzsprung–Russell Diagram
- Associated withStellar Structure
- Associated withMain-Sequence Lifetime
- Associated withRelated Concepts
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.