Definition, Meaning & Synonyms

main-sequence-star

Astronomy

/meɪn-ˈsikwəns stɑr/

Definition

A main-sequence star is a type of star that is in the stable phase of its stellar evolution, during which it fuses hydrogen into helium in its core.

Examples

The Sun is a classic example of a main-sequence star.
Other main-sequence stars include Sirius and Alpha Centauri.
As a main-sequence star ages, it will eventually exhaust its hydrogen fuel and evolve into a red giant.

Meaning

Main-sequence stars are the most common type of stars in the universe. They are characterized by their position on the main sequence of the Hertzsprung-Russell diagram, where they spend the majority of their lifetime. During this phase, stars maintain a balance between gravitational collapse and the pressure from nuclear fusion.