The full moon for September is known as the Harvest Moon, which will begin this year on September 18, according to NASA.

Every full moon has a special name derived from folklore, with examples including the Wolf Moon, the Snow Moon, the Hunter's Moon, the Sprouting Grass Moon, the Strawberry Moon, the Worm Moon, the Sturgeon Moon, the Beaver Moon, the Long Night's Moon and the Flower Moon. The names provide information about the season of month when the moon occurs.

The Harvest Moon falls the closest to the autumnal equinox, which begins autumn in the northern hemisphere. The Harvest moon will begin on September 18, followed by the equinox on September 22.

The Harvest Moon used to light the fields for farmers who had to work after sundown to harvest all of their crops, making the moonlight an essential part of farming in the days before electricity.

The Harvest Moon also marks a change in daylight. Through most of the year, the moon rises approximately 50 minutes later each day. However, near the autumnal equinox, the change is only approximately 30 minutes each day. This means the moon rises at sunset.

This is because the moon's orbital path makes a narrow angle with the evening horizon, according to NASA. This means that for several nights, the moon rises at sunset, becoming red from clouds and dust, creating the illusion that the moon is much larger than it actually is.

The moon ends up looking like a red pumpkin, which is seasonally appropriate during harvest season, especially as Halloween approaches in a little more than a month.

On sundown on September 18, sky-watchers can go outside and end the day with the Harvest Moon, signaling the beginning of the fall season and the end of the summer crops with the harvest.

Video of the Harvest Moon.