Red giant and asymptotic giant branch

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What happens when the core runs out of hydrogen. With no fusion to hold it up, the inert helium core contracts and heats, hydrogen ignites in a shell around it, and the enormous energy flux from that shell forces the envelope outward until the star is hundreds of times its former radius and, because that huge surface radiates at low temperature, red. In stars of roughly 0.5 to 2 solar masses helium ignition occurs abruptly in a degenerate core - the helium flash. Later, on the asymptotic giant branch, helium and hydrogen burn in alternating shells and the star loses between roughly forty and eighty per cent of its mass in slow dusty winds over a few hundred thousand years. The counter-intuitive part is worth stating plainly: a star gets larger and brighter, not smaller and fainter, when it exhausts the fuel in its core. Not a place.

A node is not a place. Drawing it on a map would assert something about the world that no stored fact supports.