The weather’s getting colder. The Pumpkin Spice Lattes are getting warmer. And the talk of the Song of the Summer is fading as your seasonal affective disorder kicks in. It’s almost autumn! But not until the September Equinox, on September 23 this year. Grab your denim jacket, start thinking about your Halloween costume, and put on something nice and autumnal.

There are almost entirely equal amounts of day and night on the September Equinox, which officially happens on September 23 at 8:21 p.m. Coordinated Universal Time (that’s 4:21 p.m. Eastern, for some context) when the sun shines directly over the equator.

A lot has changed since last year’s September Equinox. On September 23, 2014, according to The Week, Ebola was still in the news and Justice Elena Kagan was officiating her first same-sex marriage. How quaint we were in our pre-Obergefell v. Hodges days. Enjoy the 2015 September Equinox, friends. (There might even be an apocalypse!)

The next equinox is March 2016 at 4:30 p.m. Eastern. Welcome, fall.

Photos via How an Equinox Looks from Space, via YouTube