The Moon Illusion

[seeder]

ha I stumbled across this link just now. I too have seen the Moon look massive when rising, one time I was so excited I pulled over into a layby to take photos - even tho my missus wasn't very happy with me, (she not into space and stuff like that at all)

The moon illusion - Andrew Vanden Heuvel

[seeder]

A wiki

The Moon illusion is an optical illusion in which the Moon appears larger near the horizon than it does while higher up in the sky. This optical illusion also occurs with the Sun and star constellations. It has been known since ancient times, and recorded by numerous different cultures. The explanation of this illusion is still debated

http://en.wikipedia.org/wiki/Moon_illusion

[Waspie_Dwarf]

seeder, you might be interested in some of the posts on this illusion from a topic back in January: http://www.unexplained-mysteries.com/forum/index.php?showtopic=241314&st=0&p=4628752&hl=+moon%20+illusion%20+horizonentry4628752

[seeder]

seeder, you might be interested in some of the posts on this illusion from a topic back in January: http://www.unexplain...n

hmm ok, clearly I need to vary my search parameters!

[StarMountainKid]

Great video. I'd like to keep this thread open. So, if everyone sees the moon larger on the horizon and smaller than that at its zenith, does anyone really know the size of the moon as viewed from earth?

Edited September 10, 2013 by StarMountainKid

[Asadora]

Great video. I'd like to keep this thread open. So, if everyone sees the moon larger on the horizon and smaller than that at its zenith, does anyone really know the size of the moon as viewed from earth?

Does this help?

"The present set of orbital dynamics and distances allow solar eclipses because the Sun and Moon have the same angular size (approximately 0.5°) when viewed from Earth. The average human thumb, held out at arm's length obscures approximately 0.5° degrees and will thus, block both the Sun and Moon."

http://www.enotes.com/topics/moon/reference

Kind Regards

[StarMountainKid]

The present set of orbital dynamics and distances allow solar eclipses because the Sun and Moon have the same angular size (approximately 0.5°) when viewed from Earth. The average human thumb, held out at arm's length obscures approximately 0.5° degrees and will thus, block both the Sun and Moon."

Thanks for the info. What I was trying to get at is, human vision is a subjective experience (as this thread demonstrates). Does the mind portray the external world exactly as it is, or is the mind's image of the world different from its actual reality?

The angular size of the moon is 0.5 degrees, but our visual image of the moon determines what a 0.5 angular size looks like to us.

[Asadora]

Thanks for the info. What I was trying to get at is, human vision is a subjective experience (as this thread demonstrates). Does the mind portray the external world exactly as it is, or is the mind's image of the world different from its actual reality?

The angular size of the moon is 0.5 degrees, but our visual image of the moon determines what a 0.5 angular size looks like to us.

So you weren't meaning in actual science just 'subjective' conclusions?

I'm sorry, I thought this thread was based on -actual science- tangible science.

Did not know it was about subjective external world realities.

I'll go away now.

[Sundew]

Hmmm, I had always thought that the moon and sun look bigger on the horizon because you are seeing then through more atmosphere when they appear close to the earth, and the denser atmosphere scatters more light making them appear bigger.

[Waspie_Dwarf]

Hmmm, I had always thought that the moon and sun look bigger on the horizon because you are seeing then through more atmosphere when they appear close to the earth, and the denser atmosphere scatters more light making them appear bigger.

I think I may have said this in the previous topic, but it's worth repeating; on a Sky at Night programme many years ago Patrick Moore got volunteers on a beach to pick up pebbles that, when held at arms length appeared the same size as the moon when it was high in the sky. They then repeated this when the moon was near the horizon. Despite the volunteers believing the moon looked larger when near the horizon, the average size of the pebbles was the same for both occasions.

A simple experiment but it ruled out atmospheric effects and showed that is simply perception that makes the moon look larger when near the horizon.

[Sundew]

I think I may have said this in the previous topic, but it's worth repeating; on a Sky at Night programme many years ago Patrick Moore got volunteers on a beach to pick up pebbles that, when held at arms length appeared the same size as the moon when it was high in the sky. They then repeated this when the moon was near the horizon. Despite the volunteers believing the moon looked larger when near the horizon, the average size of the pebbles was the same for both occasions.

A simple experiment but it ruled out atmospheric effects and showed that is simply perception that makes the moon look larger when near the horizon.

Well, I have some calipers, if I get bored one night I'll walk down to the beach and measure the rising full moon, then again at midnight.

[StarMountainKid]

So you weren't meaning in actual science just 'subjective' conclusions?

I'm sorry, I thought this thread was based on -actual science- tangible science.

Did not know it was about subjective external world realities.

I'll go away now.

I thought the thread was about a subjective illusion.

[StarMountainKid]

Ok, what about the sun? I've seen many sunset where the sun appears very large compared it its apparent size high in the sky. The size of the sun in the sunset that is happening right now is at least twice as large as it usually appears.

This doesn't happen at every sunset, though. From my experience, usually the sun appears normal size at sunrise. What is the origin of this phenomenon?

[Waspie_Dwarf]

This doesn't happen at every sunset, though. From my experience, usually the sun appears normal size at sunrise. What is the origin of this phenomenon?

Well firstly it's a very bad idea to stare at the sun.

On the whole I suspect it is the same illusion that occurs with the moon.

[seeder]

This scene wouldn't have worked well with a small moon would it?

Edited September 13, 2013 by seeder

[StarMountainKid]

Well firstly it's a very bad idea to stare at the sun.

On the whole I suspect it is the same illusion that occurs with the moon.

Then why doesn't the sun look large at every sunset, it seems to me it doesn't.

[Indiogene]

Thanx for the video, seeder...what an informative and interesting topic. The moon is a beautiful sight, esp. when it's full...and rises like a huge glowing lattern in the night sky. I would like to view a moonrise in a large open plain or in the middle of the sea without any mountains in the way.

[StarMountainKid]

Do not stare directly at the sun.

I don't want to dwell on this, but during yesterday's sunset the sun appeared a very large orange ball, this evening's sunset the sun appeared normal size. Am I the only one who watches sunsets?

[pallidin]

One way that you can trick your mind out of the moon illusion is to bend over at the waist and look at the moon upside down through your legs.

Source: http://science.howst...question491.htm

That cracks me up. Mooning the moon.

Pallidin: But officer, I'm doing a science experiment.

Officer: Yeah, whatever you say, buddy. Put your hands above your butt and don't move.

Edited September 14, 2013 by pallidin