Dude the moon is huge!

[KrazyHorse]

Oerdin, arguing classical optics with a physicist.

[KrazyHorse]

Have you been drinking tonight or something? You usually have better sense than this....

[zakubandit]

Newton's theory of the gravitational field surrounding Earth is that the pull from Earth to keep the moon in orbit is a general circle. So that the size of the moon never changes, but it's distance from Earth makes it appear larger or smaller. Gravitational patterns are not perfect circles, so perhaps the moon's larger appearance is as such due to it's gravitational pull and rotation adjusting a little. This happens more often than not. I have seen large moons and I have seen average sized *size in distance*. Same goes with all planets and suns, planets are not always in perfect circle orbit, they shift due to numerous different reasons; such as asteroid collisions.

[KrazyHorse]

Dude, I stopped believing you were real after you said that Dems were Nazis.



My hat is off to you.

(Nice try, though)

[KrazyHorse]

Are you a panda****er project?

[KrazyHorse]

Maybe you're MikeH. I've never trusted that devious bastard

[zakubandit]

What's with his triple posts? He's like a kid learning to IM for the first time.

[KrazyHorse]

Tell me who you really are. I NEED TO KNOW.

[Dinner]

I'm not claiming it is bigger! I'm saying it looks bigger; I'm saying it appears bigger. I.E. is an illusion. Stop being a **** nut. You know I am right.

[KrazyHorse]

I know this is an optical effect of the Earth's atmosphere

No, you are not even close to right.

[DaShi]

Goodbloodyhell!

Here's what some Korean named Jun Moon has to say about it:

http://science.nasa.gov/headlines/y2005/20jun_moonillusion.htm

June 20, 2005: Sometimes you can't believe your eyes. This week is one of those times.

Step outside any evening at sunset and look around. You'll see a giant moon rising in the east. It looks like Earth's moon, round and cratered; the Man in the Moon is in his usual place. But something's wrong. This full moon is strangely inflated. It's huge!

You've just experienced the Moon Illusion.

Sky watchers have known this for thousands of years: moons hanging low in the sky look unnaturally big. Cameras don't see it, but our eyes do. It's a real illusion.

This week's full moon hangs lower in the sky than any full moon since June 1987, so the Moon Illusion is going to be extra strong.

What makes the moon so low? It's summer. Remember, the sun and the full Moon are on opposite sides of the sky. During summer the sun is high, which means the full moon must be low. This week’s full moon occurs on June 22nd, barely a day after the summer solstice on June 21st--perfect timing for the Moon Illusion.

When you look at the moon, rays of moonlight converge and form an image about 0.15 mm wide in the back of your eye. High moons and low moons make the same sized spot. So why does your brain think one is bigger than the other? After all these years, scientists still aren't sure why.

A similar illusion was discovered in 1913 by Mario Ponzo, who drew two identical bars across a pair of converging lines, like the railroad tracks pictured right. The upper yellow bar looks wider because it spans a greater apparent distance between the rails. This is the "Ponzo Illusion."

Some researchers believe that the Moon Illusion is Ponzo's Illusion, with trees and houses playing the role of Ponzo's converging lines. Foreground objects trick your brain into thinking the moon is bigger than it really is.

But there's a problem. Airline pilots flying at very high altitudes sometimes experience the Moon Illusion without any objects in the foreground. What tricks their eyes?

Maybe it's the shape of the sky. Humans perceive the sky as a flattened dome, with the zenith nearby and the horizon far away. It makes sense: Birds flying overhead are closer than birds on the horizon. When the moon is near the horizon, your brain, trained by watching birds, miscalculates the moon's true distance and size.

There are other explanations, too. It doesn't matter which is correct, though, if all you want to do is see a big beautiful moon. The best time to look is around moonrise, when the moon is peeking through trees and houses or over mountain ridges, doing its best to trick you. The table below (scroll down) lists moonrise times for selected US cities.

A fun activity: Look at the moon directly and then through a narrow opening of some kind. For example, 'pinch' the moon between your thumb and forefinger or view it through a cardboard tube, which hides the foreground terrain. Can you make the optical illusion vanish?

Stop that! You won't want to miss the Moon Illusion.

KH is clearly aware of this site, since his pic was lifted off of it. So he could have kindly provided a link. But before you all go off saying, "DaShi, you spoiled it. You big spoilysport." I'm quite confident that the article is vague enough to keep this discussion going for at least half a page longer.

[KrazyHorse]

Actually, DaShi: I lifted the pic from the APOD, Jan. 30 2002

http://antwrp.gsfc.nasa.gov/apod/ap020130.html

NASA's just reusing its old image files

Check yo'self before you wreck yo'self

[DaShi]

I believe you. But you could have given the poor boy a little guidence.

[KrazyHorse]

Guidance?

http://tinyurl.com/nbh8ca

[DaShi]