About 4.5 billion years ago, our planet was hot, like really hot, and any water around was in the form of vapor, basically steam. Water didn't just magically appear; it arrived in style, hitching a ride on comets and icy asteroids. These icy travelers smacked into Earth, bringing precious water molecules with them. Our planet's belly, the mantle, had its own water stash. Through volcanic eruptions, this water vapor from the mantle was released into the atmosphere—a process scientists call "outgassing." 🌍

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