National Geographic (March 19, 2009)
"n the Northern Hemisphere spring officially begins at 7:44 a.m. ET on Friday, March 20, 2009—the vernal equinox, or spring equinox (see vernal equinox pictures).
"But don't be fooled by the old rumor that on the vernal equinox the length of day is exactly equal to the length of night.
"The true days of day-night equality always fall before the vernal equinox and after the autumnal, or fall, equinox, according to Geoff Chester, a public affairs specialist with the U.S. Naval Observatory in Washington, D.C.
" 'Exactly when it happens depends on where you are located on the surface of the Earth,' he said. "
Seems that it's "a matter of geometry, atmosphere, and language."
Here in the center of Minnesota, the view out my window isn't all that springlike, in the conventional sense of the word.
See what I mean? This is what an intersection in Sauk Centre, Minnesota looked like this morning. In the unlikely event that you want to see the current state of the melt, check out the webcam at Small Town America: Central Minnesota.
Back to the equinox. National Geographic's explanation of the 'equal day and night' oddity makes sense: it has to do with the way the equinox, sunrise, and sunset, are measured.
As for me, I'm looking forward to green grass, singing birds, and all that springy stuff. Which, generally, happens a few weeks from now, after the snow melts and temperatures stay above freezing through the night.
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