Sometimes in the early night hours as the moon appears over the horizon the moon looks huge but as it moves overhead in the sky its apparent size gets much smaller. I would think that the moon at the horizon is further away from me than when its directly above.
2006-10-12 07:30:56 · 9 answers · asked by abel g 2 in Science & Mathematics ➔ Astronomy & Space
The horizon is only ten miles away. :-)
You are looking through a thicker layer of atmosphere and it acts as a lens, when the moon is on the horizon.
The sun appears the same way.
2006-10-12 07:35:00 · answer #1 · answered by Anonymous · 2⤊ 2⤋
True, the moon is physically farther away, although the amount is miniscule.
The moon *appears* larger because of 1) proximity to things on the horizon, and 2) diffraction of the light through the atmosphere (which also accounts for the tawnier color).
However, if you make an objective measure of the moon's diameter (as opposed to the subjective measure) -- say, by taking a ruler outside with you and measuring the apparent diameter when you hold the rule at arm's length -- you will see that it is an optical illusion.
2006-10-12 14:35:56 · answer #2 · answered by Dave_Stark 7 · 0⤊ 0⤋
The atmosphere acts as a prism not a lens. The refraction and scattering gives the Moon its orange color at moonrise. The Moon only looks larger because you have some foreground objects to compare it to. It is the same size in the sky. Try an experiment, tak a ruler and hold it out at arms length to measure the size of the Moon. Do this both at moonrise and when it is overhead and compare your results. You will find they are the same. Your ccomment about the Moon being farther away at moonrise is true. It is one Earth radius farther away so it actually should be about 1.6% smaller when it rises than when it is overhead.
2006-10-12 14:39:42 · answer #3 · answered by Pretzels 5 · 0⤊ 0⤋
It's an optical illusion. It appears smaller when it gets higher in the sky because there is nothing around it. You can prove it's the same size by holding a coin a certain distance from your eye so that it blocks out the moon when it's rising. A few hours later, when you think the moon looks smaller, do the same thing. You'll notice that the distance is the same.
2006-10-12 14:37:12 · answer #4 · answered by Anonymous · 0⤊ 0⤋
its all illusion...the main fact behind this in simple words is that wen the moon is near the horizon ur eye compares the moon with the object around like a buildin or a tree or anything but as it goes towards the zenith its starts lookin smaller n smaller bcoz theres nothin in the sky to which the moon can be compared......
2006-10-12 14:43:14 · answer #5 · answered by K A 1 · 0⤊ 0⤋
It's an illusion. The moon lower on the horizon looks larger because you can see houses or trees or other frames of reference. Up in the sky, there is no frame of reference.
2006-10-12 14:38:22 · answer #6 · answered by ratboy 7 · 0⤊ 0⤋
It is an optical illusion. Everything looks bigger on the horizon. Try looking at it upside down. That destroys the illusion and the Moon will look small again.
2006-10-12 14:36:39 · answer #7 · answered by campbelp2002 7 · 0⤊ 0⤋
The slant distance through the atmosphere magnifies the appearance. It's not that the moon's size changes, just your perspective of it
2006-10-12 14:40:04 · answer #8 · answered by lowflyer1 5 · 0⤊ 0⤋
the Moon is not changing size, and the distance to the moon changes negligibly
2006-10-12 14:34:19 · answer #9 · answered by Anonymous · 0⤊ 0⤋