Just as the Earth wasn't always around, it isn't scheduled to stay around forever, either.
The sun, like other stars, has a finite life span. It will grow up to be a red giant and descend into old age as a white dwarf.
And when the Sun does balloon up and become a red giant, which experts say will likely happen in a few billion years, its super-sized mass will be bloated enough to vaporize our world.
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