What event immediately forces the core of a star to begin contracting after the Main Sequence?
Answer
Exhaustion of hydrogen fuel in the star’s very center
The initiation of stellar expansion is directly tied to the termination of the primary energy source in the star's core. When the hydrogen fuel situated in the very center of the star is completely used up, the steady, outward pressure it generated suddenly ceases in that innermost region. Without this outward thermonuclear force to resist the star's own immense gravitational pull, the core is left unsupported, causing it to begin a rapid and powerful gravitational contraction under its own weight.
#Videos
Why Do Red Giant Stars Get Bigger? - YouTube
Related Questions
What balance maintains stability during a star's Main Sequence phase?What event immediately forces the core of a star to begin contracting after the Main Sequence?Where does hydrogen ignition begin after the core runs out of hydrogen fuel?Why does an expanding star like the Sun appear reddish during its late stage?How do the *size* and *mass* of a star generally change during its late expansion stage?How does the energy output from hydrogen shell burning compare to core hydrogen burning?How large might a Sun-like star swell during expansion, potentially affecting neighboring planets?What primary conversion reaction occurs in the center of a star during the Main Sequence phase?What happens to the pressure and temperature within the core during gravitational collapse after hydrogen depletion?What characteristic process occurs in the core of stars significantly more massive than the Sun during their continuous contraction phase?