The Harvest Moon got its name because the brightness allowed farmers to work in the fields after dark, making it easier to gather their crops.
The fall equinox is taking place on Saturday, September 22, but to witness the Harvest Moon, you’ll want to watch the sky at 10:53 PM EST on Monday, September 24. The sun will set at 6:49 PM on the East Coast, and the Harvest Moon will rise 12 minutes later at 7:01 PM. You’ll have all night to bask in its glow as it won’t set until 7:03 AM. While it may be visible all night, the best time to view it is close to moonrise and moonset. Once it’s high in the sky, it will be too bright to observe comfortably.
If you miss September’s full moon, you can always catch the next one, although it won’t technically be called a Harvest Moon. Occurring on October 24 this year, October’s full moon is known as the Hunter’s Moon, as European settlers and Native Americans would hunt by the moonlight in preparation for a long winter. 
H/T: Travel & Leisure