What Would Happen if the Sun Stopped? Part 2: Kelvin and Helmholtz at the Ready

What Would Happen if the Sun Stopped? Part 2: Kelvin and Helmholtz at the Ready

How can the Sun keep shining with its furnace switched off? Two nineteenth-century aristocrats, Helmholtz and Lord Kelvin, worked out the answer mostly by accident. It comes down to stored heat, gravitational shrinking, and the strange self-regulating thermostat of hydrostatic equilibrium.