Low moon, with a red tint for the past couple of nights - it's pretty and big why does it look like this?

Question

Nick, yes I do realize that. But there are times when the moon looks to "hang" very low in the sky. It doesn't always appear this way. It was 9pm when I saw it (actually, it was yesterday and not tonight).

Answer 1

The illusion to which cirric refers is explained here:

http://facstaff.uww.edu/mccreadd/

Answer 2

That's funny, I noticed the moon too last night, driving home after writing my last email to you. I too noticed that it appeared large, and I well know that its distance from the Earth varies, that the Earth's atmosphere does have a convex lensing effect, and that either man-made or natural volcanic pollution can contribute to its pinkish or reddish appearance. It is the answers though, and not your question, that is so interesting here.

“Tom A” offers a link explaining the large moon “illusion,” something written by a cognitive psychologist.(!?) Good gosh, the last thing I would ever want to do is approach a psychologist and tell them I saw something REALLY unusual and have to ask them, “Do you think I’m nuts?” The science of people studying people suffers from the obvious objectivity problem that you would think that it would have. They’re going to have to get out from behind the moon before one of them is going to try to write about it. I would read that article, but I can’t figure out why I keep thinking of screaming trees! Hahaha.

I suppose the moon could also appear to be larger when it is close to the horizon because of, as an artist would say, composition. There’s also the way it lights up more details of the horizon close to itself, and less so on the horizon farther to the left and right. A partly cloudy sky is more cloudy lower down in the sky than directly above, adding to the composition and variance of contrast. Okay, so I’ll quit laughing at the psychologist’s article and admit that yes, maybe one of those guys would have something to contribute to the discussion.

If I found separate web pages with separate, but scientific-sounding explanations for the phenomenon, as if all this was scientifically debatable, and not quickly resolvable with the simplest of communication between the two areas of science, then I will have to start laughing again.

You’re question, and the answers it prompted, was well-timed considering our off-site conversation Luci J. Did you plan that? And I want to know more about the stuff you saw, enough about me!

Answer 3

Try this:
Next time you see a "big" moon near the horizion, gauge the "size" by extending your arm to full length and hold up your thumb so you can see the relative size of the moon next to the end of your thumb.
Wait a couple of hours until the moon has risen well into the sky and repeat the measurement.
The moon looks small once it is high in the sky and the optical illusion cause by the horizion is no longer present. Your Gauge will prove that is ONLY an illusion.
That is the method I use to prove it to myself when I was a child. I never told that to anyone before, but I'm sure it will work for you also.

Answer 4

dust and other air pollution contribute to the moon appearing to look copper coloured as it rises. if you actually watch it, the colour will gradually fade as it climbs higher in the night sky. the fact that you are simply looking through more of the earth's atmosphere when the moon is close to the horizon is the reason why it appears with a deeer hue than later the same evening when there is less atmosphere between it and you, the observer. around this time of year (around harvest time...dry, dusty conditions) reddish full moons are noticeably observable.

the apparent size of moon is exactly the same (half a degree), no matter what time you observe it. it is an optical illusion created by the eye/mind when the moon is low to the horizon and near objects. pure deception on the part of the brain.

Answer 5

Our atmosphere is curved because of the shape of the earth. The atmosphere also has particles in it. The effect of being curved is that of a magnifying glass. The effect of the particles is that light will hit the particles and scatter in another direction. The scattering has a great effect on short wavelengths like blue. There is less effect on long wavelengths like red. So all told, the atmosphere is a magnifying glass with an orange tint.

When something is high in the sky, then the effects are very minimal. But when something is low, the light must pass through considerably more air to get to your eye. This causes the effects to become noticeable.

Answer 6

Sorry to contradict Cirric and his a answer but the color of the moon has little to do with the scattering of the color blue. Sadly enough beautiful red moon-rises are that way for the same sad reasons we have beautiful, red sunsets, pollution. Although it is true that the colors of the spectrum leave and exit our atmosphere in order (for instance the last color to be absorbed into the atmosphere at dusk is the color green) most colors, especially red become vivid and more visible to the human eye because of air pollution.
As for the size of the moon being larger, that is due to the time of year and the elliptical rotation bringing it closer (although slightly) to the earth.

Answer 7

Hi. The red is due to the blue light light being scattered away by the atmosphere. The 'big' is an illusion.

Answer 8

The "low" is simply the time you are looking at it, or don't you realise it rises and sets, just like the sun?