This post arrives at 1:14 a.m. EDT (5:14 UTC) on March 20, 2012, the exact moment of the vernal (or spring) equinox. As the term indicates (it is derived from the Latin aequus [equal] and nox [night], and refers to one of two times a year (the other being the autumnal equinox) when there is no tilt of the Earth’s axis with respect to the Sun. As a result, day and night are exactly equal in length (12 hours). The equinox is said to occur when the sun crosses the celestial equator. (Think of the celestial equator as a projection of the Earth’s equator out into space to create a giant imaginary ring around the universe.) Given that on this day the geometric center of the Sun is visible for 12 hours, you might think that the actual hours of daylight are precisely 12 hours. Not entirely; “sunrise” is defined as the point when the upper edge of the Sun (not its geometric center) first becomes visible above the horizon, and “sunset” is likewise defined as the point when the upper disk disappears below the horizon. A question of semantics, perhaps, but generally the hours of daylight on the equinox are a scosh longer than 12 hours. Historically, the spring equinox has been celebrated by many cultures as a time of rebirth. If you’ve ever wondered just how the bunnies and eggs got to be part of Christian celebration of Easter, it was a conflation of pagan and Christian celebrations. Pre-Christian pagan rituals featured various symbols of fertility, fecundity, and birth—rabbits (for obvious reasons), eggs, and so forth. The marshmallow Peeps are a bit of a mystery, but perhaps there was a pagan cult that venerated them, with ritual sacrifices in a microwave oven. (Never nuked a Peeps? Try it! It’s fun!) For cultures that were, for the most part, agricultural, the blossoming of trees, the imminent ability to plant and grow food again, and the marking of the end of what could be, especially in northern climes, a brutal winter were all things to celebrate. And they did. The Venerable Bede wrote that the word “Easter” itself comes from Ēostre, the Anglo-Saxon pagan goddess who was fêted for a month during what was called the Eostur-monath (April, essentially). Easter is related to the equinox in that the First Council of Nicaea (A.D. 325) decreed that the date of Easter would be (get ready...) “the first Sunday after the full moon following the northern hemisphere’s vernal equinox.” That seems needlessly complex, but it came out of a committee, so what do you expect? The equinox and eggs are also related in that there is a longstanding belief that during the equinox (and some insist only during the vernal equinox) you can stand a raw egg on its end. It is believed to have originated among the Chinese, and Facebook has helped spread this pre-urban legend in the age of social media, but it’s been around seemingly forever. And no amount of Snopes-esque debunking seems to help disabuse folks of it. There is nothing happening physically, astronomically, gravitationally, etc., during the equinox that would in any way affect the center of gravity of an egg. But I am sure when I check Facebook later on there will be photos galore of some ostensible successes, likely due to bumps and irregularities in the surfaces of some eggs that will allow them to balance—on the equinox or any other day. There is—or used to be (Googling curiously turns up few reliable sources)—a famous story that I came across in 1992 in one of Stephen Jay Gould’s “This View of Life” columns in Natural History magazine (Natural History, Dec92, Vol. 101 Issue 12, p4—sorry, no online non-library version). Gould writes that, in 1493, during a dinner held in honor of Christopher Columbus, his hosts questioned the difficulty of his voyage across the Atlantic, at which point Columbus challenged them to balance an egg on its end. (Heck of a party.) His guests all failed in their attempts, but Columbus succeeded—by cracking the shell. (Star Trek fans will immediately think “Kobayashi Maru.”) So perhaps that’s the secret. Also, too: brooms are apparently now the equinoctial objects to balance. Go figure. At any rate, happy Spring!