Final answer:
The Helium flash occurs in the core of the star and involves the fusion of helium to form carbon and oxygen. It leads to a readjustment in the star's internal structure and a brief period of stability. The final outcomes of a star after the Helium flash depend on its mass.
Step-by-step explanation:
The Helium flash occurs in the core of the star. When a star becomes a red giant and its core becomes hot enough, helium fusion begins. The fusion of three helium nuclei produces carbon through the triple-alpha process. This rapid onset of helium fusion in the core is known as the Helium flash.
The significance of the Helium flash (step 4) in the process of star death is that it marks a readjustment in the star's internal structure and leads to a brief period of stability. During this period, helium is fused to form carbon and oxygen in the core, and the star becomes hotter and less luminous than it was as a red giant.
The Helium flash differs from the earlier stages of star death because it involves the fusion of helium, whereas the earlier stages primarily involve the fusion of hydrogen. Additionally, the Helium flash leads to a readjustment and stabilization of the star's internal structure.
The final outcomes of a star after the Helium flash depend on its mass. In stars with masses about twice the mass of the Sun or less, fusion stops after the helium in the core has been exhausted. These stars become giants again and move to higher luminosity and lower temperature. Eventually, these stars exhaust their inner resources and begin to die.