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Fun Fact:


At its current rate, the moon is traveling away from Earth at a rate of 1.5 inches per year.

 

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The moon hasn't always been where it is today. As of now, the moon is about 240,000 miles away, about 30 times the radius of Earth. But when the moon was first created, it was estimated to be just 15,000 miles away from Earth. What caused it to move so far away?

On the subject of tidal forces, any physicist will tell you that no energy is free. Not only does the moon pull on the oceans of Earth, tidal friction also causes heating in both bodies. This energy must come from somewhere, and it comes from Earths rotational energy. Rotational energy from the Earth is transferred to the moon to provide kinetic energy, meaning the moon is gaining speed. Additional speed means the moons orbit is continuously increasing, though this is at an extremely slow rate.

 What the moon would look like ~15k miles away
(http://www.slate.com/content/dam/slate/blogs/bad_astronomy/2014/05/12/whatif_moon_iss_354.jpg.CROP.promo-mediumlarge.jpg)