Incoprea Theory
Vol. XIX · 50

Theory 49/Deep Time/Stellar evolution

Stars Balance Fusion and Gravity

The claim

A star's main-sequence lifetime is set by the ratio of its fuel mass to its fusion rate, which scales steeply with mass, so massive stars die young despite having more fuel.

01Mechanism

Luminosity rises faster than mass, so the ratio of fuel to burn rate falls with mass.

02Prediction

Lifetime should fall with mass despite larger fuel.

03Refutation

Lifetime tracking fuel mass would remove the luminosity scaling.