WELCOME AUTUMN!

Today (Sept. 22) marks the end of summer and the beginning of fall, also called the autumn equinox, in the Northern Hemisphere.

The autumn equinox occurs today at 4:44 p.m. EDT (20:44 UTC) when the sun is directly in line with Earth's celestial equator, or the equator projected onto the sky. Day and night last about equally long on Sunday, with about 12 hours of light and 12 hours of dark. This same phenomenon occurs on the spring equinox, which will next occur on March 20.

The date of the fall equinox (and its spring counterpart) varies slightly each year, sometimes falling on the 23rd or 24th depending on the quirks of the calendar, along with Earth's slightly irregular orbit. Here are five surprising facts about fall and the autumn equinox.

From: Livescience.