Structure of a Red Giant Star - Layered Internal Composition Explained #3674217 (License: Personal Use)

The image depicts a red giant star’s radial structure, with an outer convective envelope, a hydrogen-burning shell fusing H to He, a helium-rich intershell region, an active helium-burning core converting He to carbon and oxygen, and a growing inert carbon-oxygen (CO) core at the center. As the star evolves off the main sequence, core contraction and shell ignition drive expansion of the outer layers, leading to the red giant phase. This schematic is essential for understanding post-main-sequence stellar evolution in intermediate-mass stars.

Used in astronomy education, astrophysics textbooks, and online resources explaining stellar evolution; targets students, educators, and enthusiasts seeking to visualize how stars like the Sun evolve after exhausting core hydrogen.