Step outside any evening at sunset and look around. You'll see a giant moon rising in the east. It looks like Earth's moon, round and cratered; the Man in the Moon is in his usual place. But something's wrong. This full moon is strangely inflated. It's huge!

You've just experienced the Moon Illusion.

This week's full moon hangs lower in the sky than any full moon since June 1987, so the Moon Illusion is going to be extra strong.