#Sun

The Long-Term Future of the Sun and the Deadline for Leaving Earth

In about 5 billion years, the Sun will exhaust its hydrogen fuel and expand into a red giant, swallowing Mercury and Venus and scorching Earth. Long before that, in roughly a billion years, the Sun will be luminous enough to boil Earth's oceans. This is our civilization's ultimate deadline — and the strongest possible argument for becoming a multi-world species.