Like other stars, the Sun shines by fusing hydrogen into helium in its core. Without the power that this conversion process generates, a star would collapse under its own immense weight. The heavier the star is, the faster it consumes its hydrogen and the sooner it dies. By the time our Sun becomes a senior citizen, most of its hydrogen will be gone and its core will consist of pure helium. With no more hydrogen left at the core, the nuclear reactions that occurred there die out. And helium cannot burn at the low temperatures associated with hydrogen fusion. Without the outward pressure of…
