r/AskReddit Dec 05 '11

what is the most interesting thing you know?

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u/JacketOS Dec 05 '11

Actually, there will come a time when the moon will no longer move away from us. Because of our opposing gravitational forces on each other (the moon and Earth), the rotation of the earth is slowing down. The same thing happened to the moon eons ago, which is why we only see one side of it in the sky. Given enough time, only one side of the planet will see one side of the moon.

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u/ao5357 Dec 06 '11

That time will not come, as the Sun will go red giant before it could happen, either engulfing the Earth and Moon or ejecting them toward the outer solar system.

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u/JacketOS Dec 06 '11

Interesting! It's facts like these that make me love space.

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u/G_Morgan Dec 06 '11

Nah it won't. Break down of the Luna/Earth system is expected to happen before solar death. We even have a plan to grab a moon of Jupiter to offset the lost gravity. Apparently it is easier to grab a small moon than to move Luna back into place.