All Together Now

https://commons.wikimedia.org/wiki/File:AxialTiltObliquity.png
Image: Wikimedia Commons

A neat astronomy fact: At the equinox, the sun rises due east and sets due west at every latitude on Earth (except at the poles, where east and west are undefined).

The celestial equator is the great circle writ on the sky above our own equator. For any point on Earth (except the poles), due east and due west mark the intersection of that circle with the horizon. At the equinox the sun is on the celestial equator, so it rises due east and sets due west, not just on our equator but everywhere.

(Thanks, Sanford.)