About a month ago, the Moon was enormous, but only for two hours. Why?

It’s an optical illusion and no one really knows why it happens.

@Seek_Kolinahr

Aw thats disappointing.
Oh well. Thanks for your answer!

I think it’s interesting that everyone from Aristotle and Ptolmy to modern day astronomers have thought about this issue, and no one has a theory that sticks.

If you hold your arm out and measure it with a ruler, it will be exactly the same size on the horizon and up in the sky.
http://www.badastronomy.com/bad/misc/moonbig.html
http://www.lhup.edu/~dsimanek/3d/moonillu.htm

I would say optical illusion, no other explanation seems viable especially since it was noticed by a small group of people.

The optical illusion is based (at least in part) on the the fact that near the horizon, the moon is seen against a backdrop of distant objects such as trees and buildings, When it’s higher in the sky, on the other hand, it seems smaller (even though the disk still subtends about ½ a degree across) because it’s more isolated in a big sky with no contrasting visual cues.

A recent theory about the illusion. http://www.technologyreview.com/view/509966/moon-illusion-new-theory-reignites-debate-over-why-moon-appears-larger-near-the-horizon/

It was in its closest point to the Earth for the year. Check the asteorology events of the year.

It always looks bigger those times when it’s very low on the horizon because you can compare it to things here on Earth like a building in the foreground or something so it seems enormous. But that beautiful baby is always the same size