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Feature

A photo of an egg.

There's a persistent myth around that says you can balance a raw egg on its end only on the vernal equinox. That's cracked.

The vernal equinox: fact and fiction

fact and fiction

By Rick Moore

Peering out the window on the second to last day of winter at the gently falling snow (which somehow has lost its December luster), there's comfort in knowing that spring is just around the corner. Saturday, March 20, marks the vernal equinox for those of us in the northern hemisphere. And just what does that mean? Here are some facts, figures, and tidbits related to that benchmark time of the year when daylight begins to reign and we put our mukluks in the back of the closet--still within reach, of course.

"Equal night"... more or less

Equinox translates to "equal night." Twice a year the sun shines directly on the equator, providing equal amounts of light and darkness all over the earth. The vernal, or spring, equinox usually occurs on March 20 or 21, and the autumnal equinox takes place on September 22 or 23. You would think, then, that we would have exactly 12 hours of daylight on March 20, right? Not exactly. Due to the refraction of the sun's rays through our atmosphere, the sunrise we see precedes the actual sunrise, and the apparent sunset arrives similarly later to our eyes, so we actually have a few minutes of extra daylight on the equinox. Strange, but true.

Speaking of sunrises and sunsets, beware around equinox time while driving straight west at sunset and straight east as the sun is rising. The sun will be directly in your eyes at the horizon.

Tilt-a-world on the merry-go-round

The rest of the year we are blessed and/or cursed by the tilt of the earth, whose axis lies at approximately a 23-degree angle from the plane of our orbit around the sun. At the summer solstice, the northern hemisphere is pointed most directly at the sun. Six months later, at the winter solstice, we are pointed away, and the lower angle at which the sun's rays pass through our atmosphere makes our temperatures lower. For a crude visualization, picture yourself riding on a merry-go-round with your head acting as the earth and the center pole (at ear level) being the sun. Tilting your head 23 degrees toward the middle represents the sun's angle in the middle of summer, with the top of your head being the north pole. (Even if your spin your head, mimicking the earth's rotation during a day, it will still point at the sun, explaining the perpetual daylight in the summer above the Arctic Circle.)

Ritual and religion

As with many dramatic astronomical moments, the equinox holds significance within various belief systems and practices. The vernal equinox has been observed in various ways in Paganism, sometimes celebrating rebirth or fertility. The Sphinx was built so that it points directly at the rising sun on the day of the vernal equinox. Among indigenous groups, the Lakota hold a ceremonial hike in the Black Hills on the equinox. And the date is significant in Christianity, as Easter always falls on the first Sunday after the first full moon following the equinox.

Speaking of Easter, what about balancing eggs?

One of the more persistent myths floating around is that you can balance a raw egg on its end only on the vernal equinox. Where better to investigate a myth that the World Wide Web--the place where myths take on a life of their own. Sadly, sites claiming the validity of this theory are hard to find. And apparently our fondness of the egg theory has made America the subject of a snide remark or two, courtesy of the BBC. "One rather curious misconception surrounding the vernal equinox is that it is sometimes claimed that on this [day] it is possible to stand a raw egg on its end," says a BBC story. "This nonsense is popular on the other side of the Atlantic. In case it should gain a foothold on this side, then yes, an egg can be stood on its end on the date of the vernal equinox. But then the same feat can be achieved on any other day of the year."

Apparently all it takes is a steady hand and a bit of patience. And starting March 20 at 12:49 a.m. CST, you'll have six months straight of extended daylight during which to practice. Happy Spring!