Why does the Moon look so huge on the horizon?
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Why does the Moon look so huge on the horizon?
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Re: Why does the Moon look so huge on the horizon?
#2It's a purely psychological effect.
When it's way overhead - it's the moon. You've seen it all your life. It's just there.
When it's on the horizon - your automatic distance-judging machinery (we're talking more than just parallax and depth perception here - I mean the whole process) says "hey that thing is really far away, and way, way past the horizon, way further away than those mountains, so it's obviously really, really big by comparison (which is completely true).
Humans perceive the world more or less on a horizontal plane - so we interpret things in that plane differently than we do things above/below us.
Re: Why does the Moon look so huge on the horizon?
#3As far as I knew the illusion was caused by light scattering and refraction:
"The distance from the surface to 300 mb averages 9,300 gpm. When the sun is directly overhead, radiation passes through 9,300 meters of atmosphere between the surface and 300 mb. When the sun is at an angle, it must pass through a greater length of the atmosphere before reaching the surface. When the sun is passing through the atmosphere at a 45 degree angle, the radiation must pass through 13,000 meters of atmosphere between the surface and 300 millibars. When the sun is passing through the atmosphere at a 5 degree angle, the radiation must pass through 107,000 meters of atmosphere between the surface and 300 millibars.
"The amount of scattering and refraction differential depends on how far the sun's radiation must pass through the atmosphere. As the length of passage of light through the atmosphere increases, the amount of scattering and the refraction differential increase. When the sun or moon are within about 10 degrees of the horizon, they have the illusion of looking much bigger than they do higher in the sky and the coloring looks different. This increase in scattering is also the cause of sun sets and sun rises giving a red color on the horizon. Although the size looks different when close to the horizon, it is mostly an illusion."
Taken from http://www.theweatherprediction.com/habyhints/215/
Re: Why does the Moon look so huge on the horizon?
#4As far as I knew the illusion was caused by light scattering and refraction: "The distance from the surface to 300 mb averages 9,300 gpm. When the sun is directly overhead, radiation passes through 9,300 meters of atmosphere between the surface and 300 mb. When the sun is at an angle, it must pass through a greater length of the atmosphere before reaching the surface. When the sun is passing through the atmosphere at…
That's what I thought - but the illusion in question doesn't work if you take a photograph. It's purely psychological.
Re: Why does the Moon look so huge on the horizon?
#5It's a purely psychological effect. When it's way overhead - it's the moon. You've seen it all your life. It's just there. When it's on the horizon - your automatic distance-judging machinery (we're talking more than just parallax and depth perception here - I mean the whole process) says "hey that thing is really far away, and way, way past the horizon, way further away than those mountains, so it's obviously really…
A camera is not susceptible to psychological effects i believe. Will it be bigger on a picture?
Re: Why does the Moon look so huge on the horizon?
#6The next time you see the moon like that, turn your head sideways: It won't be so big anymore.
The psychological effect depends on the horizon. Tilting your head to the side alters the horizon's alignment, so the moon next to "some straight, vertical line" doesn't appear as big.
Re: Why does the Moon look so huge on the horizon?
#7It's a purely psychological effect. When it's way overhead - it's the moon. You've seen it all your life. It's just there. When it's on the horizon - your automatic distance-judging machinery (we're talking more than just parallax and depth perception here - I mean the whole process) says "hey that thing is really far away, and way, way past the horizon, way further away than those mountains, so it's obviously really…
You're supposed to try putting your head between your legs to look at the regular moon upside down to get the same effect (I'm not kidding).
Re: Why does the Moon look so huge on the horizon?
#8It's a purely psychological effect. When it's way overhead - it's the moon. You've seen it all your life. It's just there. When it's on the horizon - your automatic distance-judging machinery (we're talking more than just parallax and depth perception here - I mean the whole process) says "hey that thing is really far away, and way, way past the horizon, way further away than those mountains, so it's obviously really…
A camera is not susceptible to psychological effects i believe. Will it be bigger on a picture?
The camera isn't, but our brain still is when we process the picture taken by the camera.
Re: Why does the Moon look so huge on the horizon?
#9Earlier quoted context omitted.
A camera is not susceptible to psychological effects i believe. Will it be bigger on a picture?
The camera isn't, but our brain still is when we process the picture taken by the camera.
But the key point is having some other objects in the picture that will give you the perspective change.
Re: Why does the Moon look so huge on the horizon?
#10This explanation works, but there's another: On the horizon, you have things to compare it against. It looks the size it is. In the middle of the sky, there's nothing but a large black field with a small circle: it looks smaller than it is, because it's overwhelmed by the larger field. It's a very well known effect in the art world.