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How Far Away Is The Horizon?

Here’s a neat question you may have never thought to ask. How far away is the horizon?

Flat Earth

Think about it. The Earth ems flat from our viewpoint, and if you are in a dert or out at a you get a n that the earth extends indefinitely in every direction. This isn’t correct, though; the planet is round, so at some point the ground must drop away. When it drops below your angle of vision, you can’t e it any more, and that’s what we call the horizon.

So how far can you e before the planet curves away? If you’re six feet tall, the answer is about three miles. Surprid? You aren’t alone. Try asking a friend next time you’re at the beach on a clear day to guess how far out across the ocean you are looking. She’s more likely to say twenty or fifty miles than just three.

Where Is The Horizon Line?

Now that we’re thinking about horizons, here’s another cool thing to think about. The horizon is three miles away on earth. But elwhere in the solar system it’s clor or farther, depending on the size of the body you’re standing on!

Take the moon. The moon is two thousand, one hundred and sixty miles in diameter, only about one quarter the size of the earth.

So the curvature at its surface is much more noticeable, and the horizon is much clor. It’s only about 1.5 miles away.

One cool result? The surface bends so quickly on the moon that it’s possible to stand inside some of the largest impact craters and not know you’re in one. The walls of the crater are below the horizon on all sides!