what happens when a main-sequence star exhausts its core hydrogen fuel supply?
What happens when a main-sequence star exhausts its core hydrogen fuel supply? The core shrinks while the rest of the star expands. The main source of energy for a star as it grows in size to become a red giant is _____. hydrogen fusion in a shell surrounding the central core: What is a helium flash? The sudden onset of helium fusion in the core of a low-mass star