The Amazing Mystery of the Moon

[esldude]

I am sure we have all witnessed the rising of a full moon. What is a mystery and amazing is how the moon changes size. From the time the moon first pokes over the very edge of the horizon until it is higher in the sky there is at least a 3 to 1 if not a 4 to 1 size difference. And while this is observed by billions of people no one can explain it.

 

How can the size of the moon possibly change? And why only the moon? What is uniquely special about it?

[esldude]

Because it's along the horizon, the moon has something to be scaled by. If you hold your thumb up next to the moon at the horizon and then after it is higher in the sky, you will soon find out it's really the same size. My second hobby is astronomy. I also take deep sky images of nebulas.

 

So you don't trust your eyes?

 

When you start measuring with your thumb that is different than simple natural visual perception.

[esldude]

Expectation bias?

 

Nope, I don't recall ever having any expectation about the moon changing its size in the sky. I simply observed that it is large at the horizon and then gets smaller. I don't remember someone telling that it was going to happen. My first memory of it I was riding in a VW bug with my aunt when I was 4 years old. It was early evening and I was looking at the moon rise out the windshield. I asked my Aunt why the moon is big and then gets smaller after we had been riding a long time and it was so clear the moon was shrinking. She didn't have an answer for me. No one to this day knows how that happens.

[esldude]

It is not an illusion the moon is changing in size. Plenty of science to back that up.

[esldude]

Has it been under inflated?

 

Over-inflation would seem to fit the facts. Though inflation is not an idea I have given much thought.

 

I will be away from computer access for a few hours. Hopefully when I check back in we will have some good discussion on the matter. It really is a fascinating phenomenon that has not been fully explained even though we have landed men on the moon multiple times.

[esldude]

Is this really a serious question????

 

Yes it is. From wikipedia:

 

A central question pertaining to the Moon illusion, therefore, is whether the horizon moon appears larger because its perceived angular size seems greater, or because its perceived physical size seems greater, or some combination of both. There is currently no firm consensus on this point. Most recent research on the Moon illusion has been conducted by psychologists specializing in human perception. After reviewing the many different explanations in their 2002 book The Mystery of the Moon Illusion, Ross and Plug conclude "No single theory has emerged victorious".[7] The same conclusion is reached in the 1989 book, The Moon Illusion edited by Hershenson, which offers about 24 chapters written by different illusion researchers.

 

There are many variations on the illusion theory. None actually fully fit the observed facts and truly explain. Some contradict each other. No one knows.

 

Now it is my opinion the insistence the size of the moon changing is an illusion is very wrong headed. Until people open their minds to other hypothesis which don't require it being illusion there will be no satisfactory explanation. Do these people really believe billions of people are deluding themselves when they see the size of the moon change? With this many observations all agreeing to dismiss them is a serious mistake.

[esldude]

Measurements don't tell the whole story. Maybe we are measuring the wrong thing.

 

If esldude says he sees the moon getting smaller, we can only conclude that it is getting smaller, at least for him.

 

Exactly. You either trust your eyes or you don't. I have done measurements myself, I have dabbled in astronomy on and off for most of my life. When you see it, and then measurements paint a different picture either your eyes are wrong or measurements are wrong. As vision is the most highly developed sense of human perception we must be measuring the wrong things. I see no other conclusion.

[esldude]

The simple answer is that the moon is made of shakti stones and becomes depleted during the night by crazed audiophiles. When the moon is reincarnated in the next evening, the process repeats itself.

 

Come on now. Be serious. We are talking visual perception here.

[esldude]

Photographers often add people or some known object/being when framing landscapes to add scale.

 

I think that the same mechanism is at work here: when the moon is higher up, it's size appears smaller for lack of visual (scale) references.

 

R

 

This is another example of the obsession with the idea that the moon is not really changing size. When one can very simply see the size changes.

[esldude]

I think we need to call NASA: they surely will be able to settle the matter once and for all, confirming the moon does not inflate / deflate on a regular basis.

 

There is a good case to be made that it does indeed inflate and deflate in your terms quite regularly.

[esldude]

Ok, I'll try your double-blind then...

 

Seriously now, are you going to believe what you see or what you don't see when it comes to visual phenomena?

 

Visual phenomena is best perceived sighted. That would seem to be an obvious thing to the point of being a tautology.

[esldude]

Alternatively one can always try this "very special" technique:

 

 

This is a variation on measuring. We know the act of measurement effects the results from Heisenberg. This creates uncertainty. I feel much more comfortable with my perceptions than this process which puts a distance between the phenomena and ourselves. Sighting like this lacks precision as results vary from one lunar cycle to the next when I have done it.

[esldude]

I have noticed the same effect with the sun. The rising or setting sun seems much bigger. Same goes for planets and clusters of stars. Everything looks bigger when compared to the horizon vs up high in the sky.

 

-weldp

 

Yes, this size changing isn't limited to the moon it appears.

[esldude]

In the southern hemisphere it works the other way round...moon appears smaller than usual just after rising. Must be the Coriolis effect.

 

Now you are being patronizing and spreading false information. That is not true.

 

It is true the phases progress in opposite directions.

Does the moon look the same all round the world?