Everyone knows the Earth revolves around the Sun, which takes a year, and the Moon revolves around the Earth, which takes just under a month. So why, then, don't we have 12 solar eclipses and 12 lunar eclipses a year?
If you didn't know any better, you'd expect that each time the Moon passes between the Earth and Sun, its shadow would fall on the Earth, creating a solar eclipse, while each time the Moon passed behind the Earth -- into Earth's shadow -- you'd create a lunar eclipse. So why doesn't this happen?
