avgasstadiet

Avgasstadiet refers to the stage in a star's life cycle where it has exhausted the hydrogen fuel in its core and begins to fuse helium. This process typically occurs after a star has spent a significant portion of its life on the main sequence, converting hydrogen into helium through nuclear fusion. When the hydrogen in the core is depleted, the core contracts and heats up. This increased temperature and pressure can ignite the fusion of helium atoms into heavier elements, such as carbon and oxygen.

During the avgasstadiet, the star's outer layers expand significantly, causing it to become a red giant or, for more massive stars, a red supergiant. The star's luminosity increases, but its surface temperature decreases, giving it a reddish appearance. The duration of the avgasstadiet varies depending on the star's mass. Lower-mass stars may only fuse helium for a relatively short period before eventually shedding their outer layers and forming a white dwarf. More massive stars can continue to fuse heavier elements in successive stages, leading to more complex life cycles and potentially ending in supernova explosions. The specific fusion processes and elements produced during the avgasstadiet are crucial for the creation of heavier elements in the universe.