Today for most marks the first official day of fall.
Wednesday, Sept. 23, is the autumnal equinox, which signals the end of summer and the beginning of the transition to winter in the Northern Hemisphere. (Meteorological fall began Sept. 1.)
The exact moment of the equinox is at 3:21 a.m. CDT Wednesday.
How the tilt of the Earth affects our seasons. (NASA) On the equinox the sun shines directly over the equator, and the length of day and night is almost equal.
Almost but not quite.
We'll have a few minutes more than 12 hours of daylight on the day of the equinox, according to EarthSky.org.
For example, in Birmingham and Huntsville there will be nine extra minutes of daylight on the equinox day, according to Time and Date.com (Mobile will have an extra eight minutes). The day that comes closest to equal day and night will actually be Sept. 26 in Huntsville and Birmingham and Sept. 27 in Mobile.
Why is this? First, the sun is not a point in the sky, but a disk, which means several minutes could pass between the time the bottom of the sun touches the horizon and when it is no longer visible.
The second reason is because of atmospheric refraction, according to EarthSky. The atmosphere of the Earth bends sunlight and lifts the sun about 0.5 degree from its true position when the sun nears the horizon.
The days will progressively get shorter, culminating with the December solstice, which will be Dec. 21 at 10:49 p.m. CST.
Already craving longer days again? The spring equinox will be March 10, 2016, at 11:31 p.m. CDT.
Despite the shorter days, fall has its perks. Here are a few famous quotes about it:
"Autumn, the year's last, loveliest smile." -- William Cullen Bryant
"Every leaf speaks bliss to me, fluttering from the autumn tree." -- Emily Bronte
"Even if something is left undone, everyone must take time to sit still and watch the leaves turn." -- Elizabeth Lawrence
"Delicious autumn! My very soul is wedded to it, and if I were a bird I would fly about the earth seeking the successive autumns." -- George Eliot
"No spring nor summer beauty hath such grace as I have seen in one autumnal face." -- John Donne
"Life starts all over again when it gets crisp in the fall." -- F. Scott Fitzgerald
"Winter is an etching, spring a watercolor, summer an oil painting and autumn a mosaic of them all." -- Stanley Horowitz
"Autumn's the mellow time." -- William Allingham
"Bittersweet October. The mellow, messy, leaf-kicking, perfect pause between the opposing miseries of summer and winter." -- Carol Bishop Hipps
"Fall is my favorite season in Los Angeles, watching the birds change color and fall from the trees." -- David Letterman
