A mesmerizing moon cycle

We know how the moon waxes and wanes over a period of approximately 29.5 days. It happens so consistently that we rarely take notice of it.

In this graphic, it lays out the different phases of the moon over 2014, and shows us how the cycle shifts. Doesn't this image look like it is glowing and moving around? It seems hard for us to focus on it, and our eyes prefer to move around the image. Why do we feel that this is happening?

Image credit: Nicholas Ace Wiinikka

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`bold` or `__bold__`	bold
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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

The eye is taking time to receive all of the information so that the brain can interpret it so it the eye looks at the graphic as an optical illusion.

Sharky Kesa - 7 years, 5 months ago

Optical illusions in general are traits we inherited from our evolutionary past, that's why we get that sense of movement which could be a handy ability for noticing predators and prey.

Nauoram Iuoan - 7 years, 5 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$