carbon-nitrogen-oxygen (CNO) cycle

The carbon-nitrogen-oxygen (CNO) cycle is a series of nuclear reactions in stars that convert hydrogen into helium, releasing energy that powers the star. It involves carbon, nitrogen, and oxygen nuclei acting as catalysts, helping protons (hydrogen nuclei) fuse through multiple steps. These reactions occur at extremely high temperatures in larger stars, providing the energy that maintains a star’s brightness and stability. Essentially, the CNO cycle is a natural nuclear process that sustains stars by transforming hydrogen into helium using elements like carbon, nitrogen, and oxygen to facilitate the fusion reactions.