What fundamental event triggers the red giant transformation?
Answer
Depletion of hydrogen fuel in the core
The onset of the red giant phase is triggered when all usable hydrogen fuel in the star's center is converted into helium ash, causing the core to cease fusion and contract under gravity.
Frequently Asked Questions
What phase precedes the red giant transition for Sun-like stars?What fundamental event triggers the red giant transformation?What process generates energy during the active red giant phase?Approximately how much can a Sun-like star's radius increase upon entering the red giant phase?How does the surface temperature generally change as a star becomes a red giant?What is the final remnant left behind by a low-to-intermediate mass star after its red giant phase concludes?Stars that evolve into red supergiants typically start with what minimum initial mass compared to the Sun?What condition defines the star's long, stable adolescence on the Main Sequence?What occurs after the hydrogen in the shell around the core of a Sun-like star is spent?In a red giant, how does the vastly increased luminosity relate to the surface temperature?