The heavier a star, the sooner it dies — the exact opposite of the intuition that more fuel burns longer. A star of 20 solar masses shines about 36,000 times brighter and empties its hydrogen store in roughly 10 million years, while a 0.3-solar-mass red dwarf burns so slowly that it lasts trillions of years, longer than the universe has existed, so not one has yet had time to die. The threshold near 8 solar masses splits the fates: below it, a planetary nebula and a white dwarf; above it, a supernova leaving a neutron star or a black hole.
The heavier a star, the sooner it dies — the exact opposite of the intuition that more fuel burns longer. A star of 20 solar masses shines about 36,000 times brighter and empties its hydrogen store in roughly 10 million years, while a 0.3-solar-mass red dwarf burns so slowly that it lasts trillions of years, longer than the universe has existed, so not one has yet had time to die. The threshold near 8 solar masses splits the fates: below it, a planetary nebula and a white dwarf; above it, a supernova leaving a neutron star or a black hole.
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