Today is the September equinox ! Tonight — depending on where you are on the planet; it might be morning or some part of the day — at 01:23 UTC (9:03 p.m. Eastern U.S. time) the center of the Sun will be directly over the Celestial Equator, passing from the northern hemisphere of the sky to the southern. We call that moment the equinox . It has a lot of colloquial meanings, too. Some people call it the autumnal or fall equinox, though that’s unfair to people living in the southern hemisphere, when it occurs in spring. That’s why I call it the September equinox! A lot of folks like to think of it as the first day of autumn (or spring for those Down Below) but that never sat well with me either ; the cross-quarter days six weeks after the solstices and equinoxes make better sense to me as seasonal starting dates.…