WASHINGTON (AP) — In a spectacle that might have beguiled poets, lovers and songwriters if only they had been around to see it, Earth once had two moons, astronomers now think. But the smaller one smashed into the other in what is being called the "big splat." The result: Our planet was left with a single bulked-up and ever-so-slightly lopsided moon. The astronomers came up with the scenario to explain why the moon's far side is so much more hilly than the one that is always facing Earth.

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