On Friday, it'll be officially time to break out the pumpkin spice lattes and cute sweaters (although I'm sure plenty of you have already jumped at the opportunity.) The fall equinox occurs on Sept. 22 this year, marking the second of the two points in the year where day and night are of equal length. The date also marks the true coming of autumn and the colder months of the year. Ever since humans have been able to track equinoxes through astronomy, they've used them as ways to celebrate the changes in the year. In the fall equinox's case, it celebrates the harvest season and the beginning of colder weather (which doesn't seem like much to celebrate, but nobody consulted me). Autumn equinox festivals continue to exist around the world (like in the above photo, of Druids celebrating the 2009 equinox), but celebrations and weird traditions to mark this time of year stretch back millennia, and some of them got very bizarre indeed.
Equinoxes are very powerful events in astronomy, as they symbolize the turning points of the year. The spring equinox tends to get the most attention, because it marks the beginning of planting season, fertile soils, better weather, and more vegetation, all of which were important to agricultural communities in ancient times. But autumn's equal day has attracted its share of rituals, bewildering ideas, worshipful behavior and 5,000 year old time capsules. (Yes, really.) The day holds a lot more symbolic weight than it might seem.