The moon illusion
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6
2. Troy7 commented 11 years ago
The narrator said: "The moon is exact same size as every other time you've seen it in the sky" = Wrong.
The moon is up to 14% bigger when it's physically closer to earth. It's not all an illusion, but to do with physical facts about its orbit.
http://science.nasa.gov/science-news/science-at-nasa/2011/16mar_supermoon/
The moon is up to 14% bigger when it's physically closer to earth. It's not all an illusion, but to do with physical facts about its orbit.
http://science.nasa.gov/science-news/science-at-nasa/2011/16mar_supermoon/
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6. ringmaster commented 11 years ago
Actually the moon is closer to the observer in the middle of the night. Draw two circles, one the surface of the Earth and one the orbit of the Moon and measure. You are one tiny point on the surface.
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7. Judge-Jake commented 11 years ago
This is all very well and extremely clearly explained, but wot about the big moon that you see sometimes, its like twice as big as the little moon man, I mean like its hugh you know. I actually had to duck the last time I saw it cos it was nearly touching the pavement you know, weird stuff. It's like the moon just swallowed the sun man and got massive like a big moon beach ball. spookes me out, man you know its crazy just crazy wots it all for. it's like interstella ping pong man only wiv moons..aaahhh I need some more of those little blue pills it's happening again.....
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8. Benassi-MBeon commented 11 years ago
#2 Couldnt say it better myself, +1
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10. Thanny commented 11 years ago
His explanation is completely incorrect. The large moon illusion works out on the ocean, where there are no smaller objects to compare with, as well as anywhere on land where the horizon is flat and empty.
The real cause has to do with how we perceive the dome of the sky. If you poll a group of people and ask them to point to the part of the sky that's halfway up, their arms will not have an angle of 45 degrees, but something much smaller. What it indicates is that the model of the sky in our heads is that of a flattened dome, not half a sphere. Halfway up in height is not halfway to the zenith.
That makes the moon a circle on the flattened dome of the sky. When it's at the horizon, the model says it's further away. When higher up, the model says it's closer. But it subtends the same angle in both cases (we're talking about one night here, so changes in orbital distance are irrelevant), so it's subject to the Ponzo Illusion. That illusion is simply that given two objects of the same size on our retina, the one we perceive as being further away will seem larger.
The real cause has to do with how we perceive the dome of the sky. If you poll a group of people and ask them to point to the part of the sky that's halfway up, their arms will not have an angle of 45 degrees, but something much smaller. What it indicates is that the model of the sky in our heads is that of a flattened dome, not half a sphere. Halfway up in height is not halfway to the zenith.
That makes the moon a circle on the flattened dome of the sky. When it's at the horizon, the model says it's further away. When higher up, the model says it's closer. But it subtends the same angle in both cases (we're talking about one night here, so changes in orbital distance are irrelevant), so it's subject to the Ponzo Illusion. That illusion is simply that given two objects of the same size on our retina, the one we perceive as being further away will seem larger.
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11. enuffsanuff commented 11 years ago
I'm confused by the posters screen name myself. Is it pronounced "Ran-dee-oh"
or, "Ran-dee-e-o". That "y" and "i" next to each other is messin' with me man.
Are the "y" and "i" both pronounced, or is one of them silent, what's going on here? Maybe, it's pronounced "ran-dee-eye-oh"....I'm so confused. Why doesn't he just pick the "y" or the "i" already and get rid of the other one. Why does he need both of them together, it defies all logic. It doesn't make any sense.
I'm just sayin'. Nice moon movie by the way.
or, "Ran-dee-e-o". That "y" and "i" next to each other is messin' with me man.
Are the "y" and "i" both pronounced, or is one of them silent, what's going on here? Maybe, it's pronounced "ran-dee-eye-oh"....I'm so confused. Why doesn't he just pick the "y" or the "i" already and get rid of the other one. Why does he need both of them together, it defies all logic. It doesn't make any sense.
I'm just sayin'. Nice moon movie by the way.
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13. Randyio commented 11 years ago
lol guys, well Randy is my name, and I added the IO years ago when I was applying for an email address.
I was studying computers at the time. So it actually stands for input/output.
But I just pronounce it as Ran-dee-oh.
It's been like this since 1998.
But yes it's always a hassle telling people my email addy, with the extra i.
I was studying computers at the time. So it actually stands for input/output.
But I just pronounce it as Ran-dee-oh.
It's been like this since 1998.
But yes it's always a hassle telling people my email addy, with the extra i.
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15. RandurSource commented 11 years ago
#13 what's in a name; nice to meet you Randy
+12 1. Mitak commented 11 years ago