The CNO cycle is the dominant mechanism for hydrogen fusion only in high-mass main-sequence stars because of the greater __________ their cores.

Question

Quizplus · Accepted Answer

The CNO cycle involves the fusion of hydrogen nuclei into helium via carbon, nitrogen, and oxygen isotopes. This process requires very high temperatures in the core of a star, typically above 15 million K. High-mass main-sequence stars have hotter cores than lower-mass stars, which allows the CNO cycle to dominate over other fusion mechanisms.

The CNO Cycle Is the Dominant Mechanism for Hydrogen Fusion