Helium in stars

Helium in stars is the second most abundant element, formed primarily through nuclear fusion in stellar cores. Within stars, hydrogen nuclei fuse under immense pressure and temperature to create helium nuclei, releasing energy that powers the star's brightness and heat. As the star ages, it accumulates more helium in its core, which can eventually lead to different stages of stellar evolution, such as expansion into a giant or ending as a white dwarf. Helium’s presence is essential to the processes that sustain stars and influence their life cycle, playing a key role in the cosmic cycle of matter.