Is the full moon really bigger when it's near the horizon?

September 2015 Lunar Eclipse
@TheHorse (67110)
Pleasant Hill, California
November 25, 2015 3:35pm CST
There will be a full moon tonight. I read one post yesterday about strange things people supposedly do when there's a full moon. But apparently the objective research says there aren't really differences in human behavior beneath a full moon. Hmm. Another thing many people think is that the full moon appears bigger when it's near the horizon. In actually, it isn't, though. To prove it, hold your arm out and compare the size of the moon to your raised thumb (at arm's length) as the full moon is rising tonight at sunset. It'll be about a third of a thumb wide. Then do the same later at night, when the moon is higher in the sky. The moon will be the same size. Do you know why the so-called "moon illusion" occurs? No Googling allowed (just kidding)!
8 people like this
8 responses
@amadeo (67699)
• United States
25 Nov 15
No I do not.But the moon was beautiful last night.How are you doing there.
2 people like this
@Missmwngi (10637)
• Nairobi, Kenya
25 Nov 15
Sure i saw it as well
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
I'm doing well. Just took a long hike with a kid client. Came home to see the moon full rising!
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
@Missmwngi Did you try my little experiment? Or had the full moon already passed in your part of the world?
@Missmwngi (10637)
• Nairobi, Kenya
25 Nov 15
I have no idea why
2 people like this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
It has to do with "depth cues."
@poehere (17700)
• French Polynesia
26 Nov 15
Of course it looks bigger near the horizon and when it move up in the sky it looks smaller. This is a form of an illusion or curve that causes this effect. No googling OK just a perception of why.
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
But why? Why does it looks smaller as it leaves the horizon?
@poehere (17700)
• French Polynesia
26 Nov 15
@TheHorse Cause it's so high up in the sky and you can no longer reach out and touch it. This is the same as the chicken crossing the road. Why?
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
@poehere I've never touched the moon, except when I have blue cheese on my salad. But that's just little pieces.
@LadyDuck (163489)
• Switzerland
26 Nov 15
I took a photo of the moon this morning at 5 am, it was enormous on the horizon. Yesterday it was a terrible day, I think that the full moon affects people.
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
I'm not convinced that the full moon affects people, in spite of stories that suggest crowded emergency rooms and such. My day was quite normal (except for the MyLot glitch). Took a great hike with a nice kid. Got my progress note done. Slept like a baby.
1 person likes this
@Rollo1 (16686)
• Boston, Massachusetts
26 Nov 15
I tried it! And you know what? My thumb was the same size both times!
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
I just tried it. About a third of the width of my thumb at arm's length. But it looked HUGE as it rose over the trees and hills to the East.
@Asylum (48278)
• Manchester, England
25 Nov 15
The impression is caused by the fact that while close to the horizon we have a background to mentally compare it to, whereas higher in the sky we do not.
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
Yippy skippy.
@jaboUK (54492)
• United Kingdom
25 Nov 15
I had no idea that was an optical illusion. Interesting.
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
It's something we talk about in Intro to Psychology. I'll do my best to summarize it later.
@DeborahDiane (22480)
• Laguna Woods, California
25 Nov 15
This is fascinating! I am always learning something new on MyLot!
1 person likes this
@TheHorse (67110)
• Pleasant Hill, California
26 Nov 15
Yay! Learning is good. I used to think the moon actually was bigger (or appeared bigger) because of the atmosphere or something.