How Can A Full Moon Change Size

The harvest moon: A visual guide to full moons

The most spectacular views of the full moon each month are correct when it rises over the horizon. The same thing often happens when it sets. During this fourth dimension, the moon volition often exist much larger in the heaven than any other time of night. Why is that? There are two pop explanations:

i. During sunrise or sunset, the moon is much closer, hence the larger size.

This is incorrect. While the moon is lower in the sky from your point of view, information technology is no closer to the World than whatsoever other fourth dimension of day or dark. The moon is actually further abroad from you at this bespeak than when it is straight overhead.

two. The long path through the atmosphere magnifies the moon's prototype.

When the moon first rises, the prototype has to travel through a log of atmosphere before it hits your eyes due to how low it is in the sky. That atmosphere serves equally a lens to change the size of the image before it hits your eyes.

But guess what? Any atmospheric distortion would really make the moon look smaller, not bigger. This explanation is incorrect.

And then why is the full moon so much larger when it rises or sets? By the way, the same phenomenon happens to the sun every bit it rises and sets. We know that the moon does not get bigger and smaller equally the dark goes on. (It'due south not a airship.)

Information technology turns out, and this is the most interesting part, the image of the ascension or setting moon is not any bigger than information technology is the residual of the night. To be clear, not simply is the moon the exact same size all dark long, the epitome is the same size also. Your brain is just interpreting it wrong!

This probably does not seem believable yet. How can what appears to be a behemothic moon really be the same image we see later on when the moon looks and so small?

You volition likely need more than convincing, so here are some tests you can use to convince yous that the image you come across does not change size at all.

Have a picture of the rising full moon that looks so large. The image will non testify what you think you meet. The behemothic moon you saw will wait like a normal-sized small moon in your picture — the same size as if yous took a picture subsequently on at nighttime.
Employ both of your hands and turn them into a fake telescope. Wait through your faux hand-telescope so you can see the giant moon but zero else. The moon is no longer giant. Information technology is normal-sized.
If yous are still not convinced, at that place is 1 more test. But information technology is an odd i. Bend over and await at the moon with your head between your legs. The moon that was "giant" just seconds ago is now normal-sized. You lot accept to be wondering why viewing the moon upside downwards and through your legs helps your brain prepare the size of the moon. Truth is, scientists have non been able to fully explicate why this works however but, in some way, your encephalon no longer misinterprets the moon'southward image. Mayhap this is because your brain is spending all its energy wondering why you are looking at the moon upside down and between your legs!

This is not a physics problem. This unabridged miracle can merely be explained as a psychological (brain) consequence. Your brain is beingness tricked into assertive that it is seeing a very large moon. As astonishing and powerful as our brains are, they are not perfect. Only why?

The all-time way to explicate this is to actually view another example of it. Practice a quick search for "Ponzo illusion." You have seen this before. If you look at two lines heading off into the horizon (like a prepare of railroad train tracks), so identify 2 same-sized parallel lines across those train tracks, you lot would bet lots of money that the line furthest abroad is larger than the one closer to you. Only they are the same. Look it up.

What is happening is that your brain is outsmarting itself. It knows that distant objects appear smaller, and then information technology tries to overcompensate the image as it processes it. It turns the pocket-size image into one much larger. When you retrieve about it, this is an case of how smart our brain really is — only in this case, it is too so wrong. Illusion or not, information technology'due south even so OK to relish the massive looking full moon at sunrise. It'south quite cute.

Mike Szydlowski is scientific discipline coordinator for Columbia Public Schools.

TIME FOR A Popular QUIZ

1. Why does the full moon appear so much larger on the horizon?

2. What is wrong with the two almost popular theories about this miracle?

3. If you buy a photograph of a giant rising total moon, why do y'all know it has been edited?

4. In what other means is our brain tricked into seeing something that is non really there or happening?

5. Use images on the net or a cartoon to create your own Ponzo illusion.

LAST Calendar week'S Popular QUIZ ANSWERS

1. Why are dishwashers improve for the surroundings when they use and so much electricity?

The corporeality of electricity a dishwasher uses is offset by the huge amount of water saved past a dishwasher. Providing clean h2o to people takes a huge amount of electricity.

2. Why might a family not be saving every bit much energy using a dishwasher equally they should?

If a family is rinsing every dish before putting it in the dishwasher, then the environmental benefits are being wasted.

iii. How would running the dishwasher every 24-hour interval regardless of whether it is full or not impact the environs?

All of the studies on dishwasher efficiency are done assuming the dishwasher is total. Running a partially-full dishwasher is not expert for the environs.

four. List two reasons why a dishwasher cleans so much better than hand-washing.

1. Dishwashers clean at much higher temperatures, which kills more leaner.

2. Manus-washing is ofttimes done with sponges, rags and towels that agree bacteria.

v. When does a water molecule on a dish evaporate?

A water molecule evaporates when it gains a certain amount of energy to intermission abroad.