The autumnal equinox marks the debut of the autumn (or fall, if you prefer) season. This astronomical event occurs quietly and without much fanfare in the sky (unlike the total solar eclipse back in August!). But at this moment, the “solar terminator” (the ring circling the earth, where day meets night), is perpendicular to the planet as it crosses the equator, thus illuminating the northern and southern hemispheres in equal amounts. In other words, on the equinox, the day and night periods are of roughly equal duration (12 hours). After the equinox, daylight hours in the northern hemisphere continue to decrease until the winter solstice — the shortest day and longest night of the year, after which the days begin to lengthen once again.

This year the equinox is on Friday, September 22 at 3:02 PM, Central Time. But even in the ebbing summer heat of early September, portends of autumn’s pending entrance are evident. We see the sun set noticeably earlier and find spent garden plants to uproot and pitch in the compost heap. Black walnuts fall with a thud, littering the ground and perfuming the air with their acrid, peppery aroma. And if you feed hummingbirds, you see them fattening up (like little Vienna sausages!) with frequent trips to the nectar dispenser, in preparation for their arduous, their non-stop flight across the Gulf of Mexico, to winter quarters. Continue reading “Autumn’s Equinox”