Why Does The Moon Look Bigger At The Horizon?

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Refractordude
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Why Does The Moon Look Bigger At The Horizon?

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Post by Refractordude »


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Graeme1858 Great Britain
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Re: Why Does The Moon Look Bigger At The Horizon?

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Post by Graeme1858 »


An explanation from Sky and Telescope:

https://skyandtelescope.org/observing/m ... n11252015/

Regards

Graeme
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Re: Why Does The Moon Look Bigger At The Horizon?

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Post by bobharmony »


A co-worker and I called the Smithsonian one time in the 1980s to get an explanation of the Moon illusion. They had nothing concrete to offer at the time. The explanation about it looking further away than nearby objects is called into question as the illusion also exists aboard a ship at sea where there are no nearby objects between the observer and the horizon.

I have also read that if you bend forward and look at the rising Moon between your legs (so your head is upside-down) the illusion doesn't happen. I suspect that one may have been created to see how foolish people can look sometimes. BTW, when I tried it, the illusion was still there in full force.

A fascinating topic and an interesting example of how the eye-brain connection is very hard to understand at anything beyond a chemical level.

Bob
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Re: Why Does The Moon Look Bigger At The Horizon?

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Post by helicon »


A snapshot of the full moon over the Marin Headlands that I took this morning at about 5:45 AM....
PXL_20210426_130314972.MP.jpg
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Re: Why Does The Moon Look Bigger At The Horizon?

#5

Post by goldstar »


I recall an experiment where mirrors were used to bring the moons high image down to the horizon. The effect was seen there too.
I often wonder if our inability to correctly judge altitude angles is involved.
I know at my latitude Polaris must be 45 degrees in altitude but it always looks much higher. Even in daylight if asked to point at an angle of 45 I fall very short.
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