The Exploratorium: seeing | looking at the moon/4

Why does the moon seem to move with you?
As you drive down a country road with the moon to one side of the car, nearby fences and trees whiz past you, yet the moon seems to stay in the same position relative to your eyes. The farther away something is, the harder it seems to be to get past it. This is because the angle of your direction from distant objects changes much more slowly than the angle of nearby objects. The moon is very far away (about 238,000 miles or 384,000 km), though it looks closer.

Things to do:
Hold both of your forefingers in front of your face, with your left forefinger three inches in front of your face and your right forefinger at arm’s length. Now move your head from side to side. Notice that the closer finger moves past your face much faster than finger at arm’s length.

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