The Harvest Moon
To behold the wandering moon
Riding near her highest noon,
Like one that has been led astray
Through the heavens wide pathlessIl Penseroso
The Fall equinox occurred on September 22 this year. On this date, all points on the earth's surface received an equal amount of sunlight and darkness. As it happens, the equinoxes (there is also one in March) at high latitudes mark the times of the year when the pathways of the sun and the moon through the sky make the smallest angle with the earth's horizon when they rise and set. This means that the number of daylight hours is changing fastest, and also that there is the least difference on successive nights in the hour at which the moon rises.
The Harvest Moon is the full moon occurring nearest the Fall equinox This year, it falls on October 2. The Harvest Moon, as any full moon, rises near sunset, but at this time of the year, it will appear near the same hour on several nights in succession. For several nights around the Harvest Moon, therefore, there will be bright moonlight in the early evening, and this has been a traditional aid to harvesters ever since men tilled the soil.
Because of the long path that the moon's rays must take through the atmosphere during the early evening, the blue light is scattered out of the moon beam and the Harvest Moon takes on a warm, yellowish glow.