Equinox Phenomena in Action: Video
Hooray! It's spring! On this day, March 20, 2012, the day and night are almost equally long as the sun passes over the equator in what's known as the vernal equinox.
The ancient Pueblo of Chaco Canyon were proficient in astronomy. This computer-animated video from IRC, a tech think tank, shows just what the Pueblo were capable of oh so many years ago.
The famous Mayan ruins at Chichén-Itzá and Dzibilchaltún draw thousands annually to view the sun's antics. Below, an informative video explaining Chichén-Itzá and the astronomical significance of its main pyramid and other buildings. Then we move on to Dzibilchaltún. Below, a video look at each.