Some good news, some bad news. The good news is that Earth won’t be swallowed by the Sun, at least not due to tidal forces. The bad news? We’ll never know because we won't be around.
The Sun's journey will see it expand into a red giant and then fade away as a white dwarf. But its evolution could mean our planet gets an unexpected cosmic reprieve from certain doom.
As the Sun swells, Earth’s orbit faces a complex tug-of-war between gravitational forces pulling inward and tidal forces pushing outward. Tidal dissipation, previously thought to be dominant, may not drain Earth's energy as much as we feared. Observations of other red giants hint that our planet might just survive.
But the future remains uncertain. Variables like stellar winds and thermal pulses can throw a spanner in the works, leading to different outcomes for humanity’s home. Meanwhile, Mercury and Venus will be scorched, while Mars will find a new orbit, and the gas giants could see their moons melt into watery worlds.
