Motion in the HR Diagram
				• During He core, H shell burning – Moving some of E generation back into core shrinks size (and so raises TSurface) – Eventually He in core runs out  leaving a C, O core inside the He region – Core contracts and heats up till He ignites in shell outside C, O core • During He shell, H shell burning – At first R increases, TSurface decreases – L increases as more C,O accumulate and TCore continues to increase