Lives of Stars

Part of Hall of the Universe.

Lives of stars_HERO AMNH/D. Finnin
Stars are born, live out their lives, and die.

Their appearance changes dramatically along the way. The Sun will age to become a red giant star like Arcturus. Betelgeuse will eventually resemble the Crab Nebula, exploding as a supernova and leaving behind a neutron star remnant. The fate of the supergiant star Rigel is that of a black hole like Cygnus X-1. The wide variety of stars we see represents the different stages in their lives.

Stellar Timelines

The evolution of a star is governed primarily by its mass. A star’s mass determines its nuclear fusion rate, and thus its luminosity (energy output) and its life expectancy. We define four broad mass categories, based on a star’s lifetime, how it dies, and the stellar remnant it leaves. The “life” of a star is the stable stage when it is fusing hydrogen to helium in its core.

A chart showing the lifespans, in millions of years, of different types of stars.

Birth of a Star Cluster