All you need to know: September equinox
Deborah Byrd in ASTRONOMY ESSENTIALS | September 22, 2018


Equinoxes and solstices. In each of the images, Earth’s rotational axis is perpendicular (straight up and
down), with the North Pole at top and South Pole at bottom. Earth at the equinoxes shown at right;
Earth at solstices shown at left. Images via Geosync.

The September equinox arrives on September 23, 2018, at 1:54 UTC. Although the equinox happens at the same moment worldwide, your clock times will depend on your time zone. For time zones in the continental U.S., this equinox comes on September 22 at 9:54 p.m. EDT, 8:54 p.m. CDT, 7:54 p.m. MDT and 6:54 p.m. PDT. Translate to your time zone.

At the equinox, days and nights are approximately equal in length. For us in the Northern Hemisphere, the sun is rising later now, and nightfall comes sooner. We’re enjoying the cooler days of autumn.

Meanwhile, south of the equator, spring is about to begin.