Wednesday, March 7, 2012

Full Moon.

So there is a full moon today. A BIG one. Nice and big and yellow hanging just above the horizon.

Why does the moon look so big when it is rising? No one ever tells you to go look at the giant moon when it is high in the sky. The key thing here is that the moon only looks big.

While the distance the moon is from the Earth varies slightly in its orbit (this is why some tides are bigger than others), on any given night the radius of the moons orbit does not change significantly. The moon is no bigger when it is high in the sky than when it is low on the horizon.

The main reason for this is perspective. When we see objects at a distance, they look small, but knowing in our minds what their true size is, the brain compensates and interprets the objects size accordingly. 

When the moon is high in the sky, we have nothing to compare it to, so its size means nothing. With no reference points, we perceive it to be closer than it is. When it is low on the horizon, however, we see it in relation to buildings and trees, and it looks absolutely huge.

Apparently, one way to un-trick your mind is to bend over, and look at the moon upside down through your legs.

I suppose you could also take a picture, but I loaned out my tripod... unfortunate since there is supposed to be some awesome auroras coming up!


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