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Posted: 9/27/2004 5:18:19 PM EST
When the full Moon rises, it appears to be huge! Then it appears to be normal sized once it has rises. What gives? My Astronomy teacher said it was an optical illusion.
Any comments?
Link Posted: 9/27/2004 5:19:24 PM EST
because,


Shit....


How does a posi trac in a plymouth work? huh?

it just does.
Link Posted: 9/27/2004 5:21:47 PM EST

Originally Posted By mtechgunman:
because,


Shit....


How does a posi trac in a plymouth work? huh?

it just does.


Link Posted: 9/27/2004 5:24:03 PM EST
optical illusion.
when the moon rises this time of month called the "harvest moon" the atmospheric pollution causes optical distortion and magnifies the moon
Link Posted: 9/27/2004 5:27:57 PM EST
Hold your thumb up at arms length and gauge the size of the rising moon against it. In three hours hold your arm the same way and gauge the same. Get back to us with your results.
Link Posted: 9/27/2004 5:28:56 PM EST
It is a worldwide conspiracy against you. Crap, I have already said too much.
Link Posted: 9/27/2004 5:29:53 PM EST
Its an optical illusion. It only appears larger on the horizon because there are objects to compare it to. When it is high in the sky it appears smaller because it is all by itself. Twonami is right, try it. Amaze your friends!
Link Posted: 9/27/2004 5:34:57 PM EST
[Last Edit: 9/27/2004 5:36:47 PM EST by Gunzilla]
The problem with most of these explainations is that they would seem to distort both H & V angular measure, but we all know that V measure appears smaller when the moon (or sun) is on the horizon?

There are several theories about the "moon illusion" but most have some problems... oculomotor micropsia seems to be the most recent and accepted theory, dont ask me to explain it, I only studied it when I was writing a paper on target recognition for snipers... google it

eta:btw, the difference in perceived size is different for different people... odd thing is, some think it looks smaller -- which it should, as it would be one radian further away at the horizon than when directly overhead (like I could see that difference)
Link Posted: 9/27/2004 5:37:07 PM EST
The moisture in the air causes the cheese to swell and appear larger .
Link Posted: 9/27/2004 5:39:48 PM EST
It's sort of complicated to explain from what I've read (got me curious with this)

But it's actually your brain fooling you into thinking it's bigger when rising.

Has nothing to do with the atmosphere, or pollution.

It's just distorted signals from the eye to the brain. The brain is not interpreting them correctly.

Here's a pretty good link explaining it in 'simple' terms...

www.scienceplace.org/science/moon.shtml


There's much more scientific explanations out there, but you just might see a whole lot WORSE after trying to read them
Link Posted: 9/27/2004 5:41:30 PM EST
This is lunar illusion at work: A trick of perception seems to exaggerate the size of the moon when it is near the horizon. While it is no closer or farther away from the viewer on Earth, the low-hanging moon appears a good deal larger than it seems when elevated higher in the nighttime sky.

The popular explanation is that the moon looks bigger when you have something to compare it to. Seeing the moon compared to other objects -- trees, buildings, mountains -- makes it appear larger. The moon alone in the middle of the sky has no surrounding frame of reference, so it appears smaller.

Certainly this is the case, but it doesn't explain what happens in the human brain to change the viewer's perception. Why should a comparison to features on the ground change the way we perceive the moon? What trick is the brain playing that makes the moon appear to change size?

Thinkers throughout history have struggled to explain the illusion, and today the little-understood phenomenon is still a subject of controversy.

Two opposing theories vie for acceptance, but they are contradictory: One suggests that the horizon moon appears large because visual cues in the intervening landscape make the moon seem far away. The other idea says those same cues make the same moon appear closer.

Now a father-son research team's experiments may settle the dispute. Lloyd Kaufman, a professor emeritus of psychology and neural science at New York University, and James Kaufman, a physicist at IBM's Almaden Research Center in San Jose, California, explain their work in the January 4 issue of the Proceedings of the National Academy of Sciences.

The Kaufmans argue that the explanation of the illusion lies in the fact that viewers judge a horizon moon to be much farther away than the overhead moon. The brain then exaggerates the perceived size of the moon as if to drive home this conclusion: the moon is so far away, therefore it must really be huge if it takes up so much space in the sky.

Source Full Moon in question
Link Posted: 9/27/2004 5:41:53 PM EST
horizon=^4to 6th power>{5x9} +methane{read flatuation}due to SUV cars/radius of earth square PIE.
Link Posted: 9/27/2004 5:43:43 PM EST
[Last Edit: 9/27/2004 5:44:03 PM EST by Leisure_Shoot]

Originally Posted By cyanide:
The moisture in the air causes the cheese to swell and appear larger .



where is cyanide's oft accused anger in this comment?
I laughed my ass off... see...
Link Posted: 9/27/2004 5:44:07 PM EST

Originally Posted By cyanide:
The moisture in the air causes the cheese to swell and appear larger .




And as it ripens it turns green!
Link Posted: 9/27/2004 5:47:37 PM EST
[Last Edit: 9/27/2004 5:51:31 PM EST by twonami]
The full moon that rises around the time of sunset this evening is the legendary Harvest Moon. It has that name because it's the closest full moon to the September equinox. Some say the Harvest Moon appears bigger, brighter and yellower than other full moons. But all full moons look big, bright and yellowish when you see them near the horizon. What makes the Harvest Moon special is the lazy slant of the ecliptic -- shown on our chart as a green line -- with respect to the horizon in the evening at this time of year. As the moon moves in orbit around Earth, it moves eastward approximately along the ecliptic. Most of the time, the moon's eastward motion causes it to rise about 50 minutes later each day. At this time of year, however -- around the time of full moon -- the moon rises only about 30 minutes later each day. That's why, around the time of full moon during the autumn months, the moon rises close to the time of sunset several evenings in a row. So you have several chances around now to see a big yellow moon hanging low in the sky just after the sun goes down. Before the era of tractor lights, farmers bringing in their crops could work uninterrupted by the light of this full autumn moon. Hence the name Harvest Moon.

In the northern hemisphere, the Harvest Moon is the full moon closest to the September equinox. In the Southern Hemisphere, a full moon with similar characteristics comes in March. Harvest Moons -- after this on Earth and Sky.


"Why does the moon look so close and orange sometimes?"

When you see the moon near the horizon, it's likely to look reddish in color. That's because you're looking through more of Earth's atmosphere than when you look at a moon overhead. Moonlight is reflected sunlight -- made of all the colors of a rainbow. When the moon is low, the atmosphere scatters most of the colors in moonlight. But the reddish component of moonlight travels a straighter path to your eyes -- so the moon looks reddish.

The large size of the moon seen low in the sky isn't caused by the atmosphere. It's an illusion, a trick of the eyes and brain. It's called the "moon illusion." September's moon will be full tomorrow morning, according to clocks in the U.S. We call this closest full moon to the autumnal equinox the Harvest Moon. For people in the Northern Hemisphere, this full moon will rise shortly after sunset for the next several evenings. There'll be no long period of darkness between sunset and moonrise.

In the Southern Hemisphere, this full moon is the one closest to the spring equinox. Spring full moons are characterized by long periods of darkness between sunset and moonrise on the nights after full moon. The Southern Hemisphere has a full moon that rises on a schedule like our Harvest Moon
Link Posted: 9/27/2004 5:48:20 PM EST

Originally Posted By Lion_Dog:

Originally Posted By cyanide:
The moisture in the air causes the cheese to swell and appear larger .




And as it ripens it turns green!






Link Posted: 9/27/2004 5:50:22 PM EST

Originally Posted By SigZiggy:
This is lunar illusion at work: A trick of perception seems to exaggerate the size of the moon when it is near the horizon. While it is no closer or farther away from the viewer on Earth, the low-hanging moon appears a good deal larger than it seems when elevated higher in the nighttime sky.

The popular explanation is that the moon looks bigger when you have something to compare it to. Seeing the moon compared to other objects -- trees, buildings, mountains -- makes it appear larger. The moon alone in the middle of the sky has no surrounding frame of reference, so it appears smaller.

Certainly this is the case, but it doesn't explain what happens in the human brain to change the viewer's perception. Why should a comparison to features on the ground change the way we perceive the moon? What trick is the brain playing that makes the moon appear to change size?

Thinkers throughout history have struggled to explain the illusion, and today the little-understood phenomenon is still a subject of controversy.

Two opposing theories vie for acceptance, but they are contradictory: One suggests that the horizon moon appears large because visual cues in the intervening landscape make the moon seem far away. The other idea says those same cues make the same moon appear closer.

Now a father-son research team's experiments may settle the dispute. Lloyd Kaufman, a professor emeritus of psychology and neural science at New York University, and James Kaufman, a physicist at IBM's Almaden Research Center in San Jose, California, explain their work in the January 4 issue of the Proceedings of the National Academy of Sciences.

The Kaufmans argue that the explanation of the illusion lies in the fact that viewers judge a horizon moon to be much farther away than the overhead moon. The brain then exaggerates the perceived size of the moon as if to drive home this conclusion: the moon is so far away, therefore it must really be huge if it takes up so much space in the sky.

Source Full Moon in question



I was actually using the memory recognition theory to explain parts of the target recognition section of the paper... but it was argues by the doctor I was working with that the "recognitive" image is incorrect, we all "know" the moon is round and would formulate a round moon... not the squashed moon that most see on the horizon -- this is why I think the oculomotor micropsia idea makes more sence as far as the difference between the V & H angular measure...
Link Posted: 9/27/2004 5:51:27 PM EST
[Last Edit: 9/27/2004 5:51:38 PM EST by Redcap]

Originally Posted By mtechgunman:
because,


Shit....


How does a posi trac Sure-Grip in a plymouth work? huh?

it just does.



Clutch or cone type?
Link Posted: 9/27/2004 5:51:55 PM EST
Heard a meterology prof suggest standing with the big moon to your back and bend over and look at it through your legs, and it will appear normal size. As soon as I'm sure no one is watching.....
Link Posted: 9/27/2004 5:54:24 PM EST
Cheese illusion


SGatr15
Link Posted: 9/27/2004 5:58:41 PM EST

Originally Posted By Gunzilla:

Originally Posted By SigZiggy:
This is lunar illusion at work: A trick of perception seems to exaggerate the size of the moon when it is near the horizon. While it is no closer or farther away from the viewer on Earth, the low-hanging moon appears a good deal larger than it seems when elevated higher in the nighttime sky.

The popular explanation is that the moon looks bigger when you have something to compare it to. Seeing the moon compared to other objects -- trees, buildings, mountains -- makes it appear larger. The moon alone in the middle of the sky has no surrounding frame of reference, so it appears smaller.

Certainly this is the case, but it doesn't explain what happens in the human brain to change the viewer's perception. Why should a comparison to features on the ground change the way we perceive the moon? What trick is the brain playing that makes the moon appear to change size?

Thinkers throughout history have struggled to explain the illusion, and today the little-understood phenomenon is still a subject of controversy.

Two opposing theories vie for acceptance, but they are contradictory: One suggests that the horizon moon appears large because visual cues in the intervening landscape make the moon seem far away. The other idea says those same cues make the same moon appear closer.

Now a father-son research team's experiments may settle the dispute. Lloyd Kaufman, a professor emeritus of psychology and neural science at New York University, and James Kaufman, a physicist at IBM's Almaden Research Center in San Jose, California, explain their work in the January 4 issue of the Proceedings of the National Academy of Sciences.

The Kaufmans argue that the explanation of the illusion lies in the fact that viewers judge a horizon moon to be much farther away than the overhead moon. The brain then exaggerates the perceived size of the moon as if to drive home this conclusion: the moon is so far away, therefore it must really be huge if it takes up so much space in the sky.

Source Full Moon in question



I was actually using the memory recognition theory to explain parts of the target recognition section of the paper... but it was argues by the doctor I was working with that the "recognitive" image is incorrect, we all "know" the moon is round and would formulate a round moon... not the squashed moon that most see on the horizon -- this is why I think the oculomotor micropsia idea makes more sence as far as the difference between the V & H angular measure...



Ah yes, my dear Watson. Perhaps you will find this interesting reading.... Oculomotor Micropsia
Link Posted: 9/27/2004 6:00:51 PM EST
[Last Edit: 9/27/2004 6:01:40 PM EST by SigZiggy]

Originally Posted By sgtar15:
Cheese illusion


SGatr15



So.......Wisconsinites see the largest full moon
Link Posted: 9/27/2004 6:01:04 PM EST
I thought it was the gravitational pull of the moon pulling on the metal plate in my head and squeezing my eyeballs. I feel the urge to howwwwwwwwwwwl!
Link Posted: 9/27/2004 6:04:33 PM EST

Originally Posted By SigZiggy:

Ah yes, my dear Watson. Perhaps you will find this interesting reading.... Oculomotor Micropsia



I have read through a lot of material about the subject some years ago... but thanks, seems to support what I was saying anyway?
Link Posted: 9/27/2004 6:07:50 PM EST
I read about this in Cecil Adam's column, The Straight Dope. It has to do with perspective and seeing the moon against the landscape.
Link Posted: 9/27/2004 6:07:54 PM EST

Originally Posted By Gunzilla:

Originally Posted By SigZiggy:

Ah yes, my dear Watson. Perhaps you will find this interesting reading.... Oculomotor Micropsia



I have read through a lot of material about the subject some years ago... but thanks, seems to support what I was saying anyway?



Yes, you'll get my vote for geek of the evening

Link Posted: 9/27/2004 6:24:56 PM EST

Originally Posted By Redcap:

Originally Posted By mtechgunman:
because,


Shit....


How does a posi trac Sure-Grip in a plymouth work? huh?

it just does.



Clutch or cone type?




AttaBoy ! was wonderin who'd pick up on that first
Link Posted: 9/27/2004 7:43:42 PM EST
I am in awe, the wealth of information here is astounding

[7of9]Resistance Is Futile![7of9]
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