What process allows a star to ignite heavier elements after the core hydrogen supply is depleted?

Answer

Secondary heating caused by core contraction, leading to fusing helium into carbon

When the hydrogen fuel in the core is finally exhausted, the outward pressure generated by fusion diminishes, causing gravity to momentarily regain dominance. This results in a temporary, but significant, contraction of the core. This subsequent compression generates intense secondary heating, raising the core temperature and density even further than during the main sequence. This enhanced thermal energy provides the necessary activation energy for the next set of fusion reactions, specifically allowing the existing helium nuclei to fuse together to form heavier elements, such as carbon, marking the star's entry into subsequent, often more luminous, evolutionary stages.

What process allows a star to ignite heavier elements after the core hydrogen supply is depleted?

Related Questions

What energy source drives the initial heating of the collapsing mass forming a protostar?What critical temperature threshold must the protostar core exceed for nuclear fusion to commence?What state describes the balance between opposing forces within a star during its main sequence phase?What is the specific conversion process powering the star during the Hydrogen Burning phase?What physical element contributes to the steep temperature gradient and immense pressure at the star's center?How does the lifespan of a Sun-like star compare to a star ten times its mass on the main sequence?What process allows a star to ignite heavier elements after the core hydrogen supply is depleted?What is the immediate result of converting gravitational potential energy during the initial collapse of the molecular cloud?What relationship links the star's mass to the required core temperature for maintaining stability?Which famous equation describes the energy generation far exceeding gravitational heating during ongoing fusion?
CoreheatgravitystarFusion