In this day and age, true equality is still elusive.

Even on the most equal day of the year, parity will not be found. Equal opportunity for light and dark will not exist tomorrow. Spring arrives on Saturday, March 20 this year, but this first day of spring, the vernal equinox, may not be as equal as we thought.

The word equinox is translated literally as ‘equal night,’ which naturally leads us to believe that there is an equal amount of day and night, or 12 hours of darkness and 12 hours of light. This is the first myth of the equinox, one told to you since you were in grade school. You can still find it written in books and on the Internet. But, like a lot of “received wisdom,” it bears a little more looking into to get at the truth.

Although it is close, equality eludes us on the day of the vernalequinox. That is right — let me be the one to spoil a good tale: the lengths of day and night are not equal on the equinox. Luckily, it’s not all bad news, since there is more light than dark on this ostensibly equal day. Science helps shed alittle light, too, on this mis-named day.

Two factors cause the confusion. The first is refraction. Refraction is the bending of light that occurs when the light from the setting (or rising) sun moves through the atmosphere. According to the U.S. Naval Observatory, this refraction givesus approximately 34 minutes more of light.

Another variable provides another 16 minutes of light. The sun is so large in diameter that we begin to receive its sunlight before technical “sunrise” (the point where its middle of the sun is above the horizon),and we continue to bask in its light after the sun’s midpoint has set below the horizon. 

With these two phenomena factored in, light wins out, and predominates on the supposed equal day. The true equal balance of 12 hours of day and night occurs a few days beforethe spring equinox, but by now, we have already missed it.

There is another spring equinox myth that will be busted today; this one concerns the egg, fertile symbol of the season. It is said (annually and often) that only on the vernal equinox, it is possible to stand a raw egg on its head. In truth it is possible on that day, but it is also possible every other day of the year if you have a bit of patience and talent. There is nothing cosmic or special about the day that will make a raw egg stand up on edge. How do these myths get started? It has to do with them sounding so logical and plausible. But they don’t always ring true.

Still, all things being equal (even if the length of day and night aren’t), the myths don’t affect us as much as the underlying fact that spring hassprung! This is very good news indeed for those that need a little more light in their lives. And for those egg balancers, keep trying: as Emily Dickinson said, “A little madness in the Spring Is wholesome even for the King.”

 

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.