I can’t believe we still haven’t discussed one of the most common optical illusions that we see almost each day. I’m talking about Moon Optical Illusion. The short intro would go something like this: 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 illusion also occurs with the sun and star constellations. It has been known since ancient times, and recorded by numerous different cultures. There have been numerous tries to figure out why this phenomenon occurs (check Wikipedia), and the closest one in my belief would be “Relative Sizes” explanation – something we explained in the Ebbinghaus article and the Ponzo Collection. What do you think about it? What is your explanation? Have you noticed this illusion as well?
(6 votes)
1st? i hope so!! i dont get the illusion
Nice!
A good ole classic illusion
Explaination: My brain is small and easy to trick. So is yours.
:p
sux
because earth’s slightly tilted ? O.O
i dont understand
(first comment!)
Maybe,its closer? 1st (i think)
Possible first comment again, whooo!! I dont really get the illusion- i understand it in writing but in the picture the moons jut look like the same size…
It appears larger because your eye has something to compare the moon too rather then when its high in the sky but it is still the same size no matter where it is in the sky
It happens cuz our eye has something to compare the moon too like a building unlike when its high in the sky but its always the same size no matter where it is in the sky
thats pretty sick. i always saw that, but never really thought about. i guess that it is closer to our line of vision, if not us, when it is on the horizon
(FIRST POST!!!!!)
i don’t get it…
Great illusion! I really like this common experience that the moon appears to be bigger at the horizon than higher up the ski. However I never had an idea why, but the relative sizes explanation makes sense. The picture clearly shows how the illusion works. Only when we can compare the size of the moon with other objects at the horizon, the moon seems to be bigger. Not higher up the ski, where there is nothing with which we can compare the moon with. Why is it the closest explanation for you. Isn’t it generally confirmed? It seems logical to me. Thanks for giving me the explanation for this illusion.
Because objects generally get smaller as they go into the horizon, the brain assumes that objects on the horizon are further away and must be smaller. But as the moon is the same size wherever it is in the sky, it doesnt decrease in size as it gets to the horizon and the brain thinks this must be because it is getting bigger.
I have never been able to see the moon on the horizon!! Where is the best spot to see this? and when??
top 3 ???
Don’t get the illusion here……….
Last full moon someone a freind commented about how it looked big, and we ending up talking about the illusion and how cool it was, and then we read that the moon was actually the closest it has been in ages so it wasn’t just this illusion :P
But yeah I thought this had been posted here before…? I guess not.
This is pretty cool. I am impressed that this illusion has actually occurred on our planet for a long time and that it can be translated into a 2D illusion. I gotsta check out these other relative size illusions.
When we see things near the horizon, they shrink in size. Our brain tries to put everything in perspective, so we expect distant objects to get smaller.
But since the moon is so far away, it’s distance doesn’t change much between us and the horizon.
In other words the distance between us and the moon and the horizon and the moon is, in a cosmic sense, pretty much the same.
Our brain doesn’t realize this and assumes that moon much be very large being so far away. Up high in the sky, there are no objects to act as [false] references so it appears smaller.
It’s the same when you’re driving and everything moves, but distant objects remain stagnant giving the illusion that they’re following you.
Yay!!! First comment! :)
My explanation for this is that the earth is just closer to the moon at a specific time each day.
Not very good at all, both actually look about the same to me.
Both moons are the same size
lol
That’s awesome
The moon appears larger because the distance from your eye to the moon is greatest when the moon is on the horizon. It appears “normal” when it is directly above. The atmosphere acts as a magnifier. That magnification is greatest when the the moon is low and the amount of atmosphere we look though is the greatest.
The refractive and reflexive properties of the atmosphere help explain the phenomena or illusion that the sky is blue when in fact it is mostly black!
I believe the moon looks bigger while it’s close to the horizon because we are looking at it through a thicker layer of our atmosphere which acts like a magnifying glass. When the moon (or sun, for that matter) is high in the sky we see it through a much thinner layer of atmosphere and it isn’t magnified as much. Any scientists out there to corroborate this?
Cool illusion… I also think it may be because of the relative sizes, but who knows.
(1st comment, finally) lol
It’s a great illusion, but it’s just perspective, hence the train tracks.
In the distance it looks bigger because the closest things to relate it to are small (in the distance), but when it’s closer or higher in the sky, the only things to relate it to are bigger (closer to you)
Relativity, right?
very traditional; but cool.
In my opinion, it is another example of perspective modification… :) Many examples of this illusion (although most don’t talk about the moon) :)
First post? May be a first for me…
1st
its easy
the sun and moon grow larger and smaller at the start and end of each day because they are tired
DUH
Hi,I’m _____ and I also saw a illusion with the train tracks.WoooHoooooo FIRST COMMENT IF SO IN YOUR FACES MOTHR LOVERS!!!
real strange
1st comment? cool^^
It’s perspective, of course. When the moon is high in the sky, there is nothing around it to compare its relative size to, so it looks rather small out there in the big black darkness.
But when it’s near the horizon, we compare the horizon with the size of the moon, and it looks bigger. Also, it reflects more light onto our eyes when near the horizon, so we get the illusion of seeing “more” of it.
Nice illlusion, btw. =
The moon looks larger when it is lower on the horizon because you are looking thru a longer section of atmosphere which acts as a magnifier.
This is the granddaddy of optical illusions. I have marvelled at it since I was a kid and love the arguments with people when they think the moon actually is bigger on the horizon. No illusion site would be complete without it. ;-)
An oldie but a goodie
Great sight though, you keep up the good work and I’ll keep telling everyone I know about it!
I like this one. Great site. You keep up the good work and I’ll keep telling everyone I know about it.
cool
well, relative size would be a very good explanation.
See for yourself: the moon in the front is laying next to the track, but the moon in the back would cover both tracks and very far beyond them… That is what your mind tells you (or me).
The tracks gives you a perspective, and thus a reference to sizes.
Without them, yes, both moons are equal in size.
Keep up the good work!
peace
It’s an amazing thing, this Moon illusion. I once heard that the horizon moon appears smaller when you’re standing on your hands.
that’s weird.
are the two moons in the picture the same size?
ive seen it bofore
This is especially true at Easter (when I think the Moon is closest to the Earth…I may be wrong on this.) The moon looks huge at this time – it is an amazing illusion.
Although this is a familiar way of illusions, it’s keeps interesting!
I think it’s more the apparent distance explanation; because for example, when the moon rises over sea, it still looks bigger. But on sea there is no size reference.
thats awesome i did wonder why the moon was bigger at the horizon but i thought it was justr closer to the earth lol XD but thats awesome
A while ago (I think I was still in college) I got into an argument with my grandpa about the moon. I had just been told about it’s size not changing, and after making sure it was so, I told him about the illusion. He kept telling me I was wrong; that it was closer when it was rising. Had I not measured for myself, I would have agreed. to this day, on full moons, I give it the thumb test. It still makes me smile
Yes, it is quite apparent. The rising moon (especially when full) as it catches hues from our polluted atmosphere, always seems larger than reality. Then, when so far away… appears small and almost insignificant.
Why do people care if they are the first comment?!? Half the time they aren’t! I don’t get it. It’s about the optical illusion, not a race to be the first to comment…