September 19th is our next Full Moon and the Full Moon that occurs closest to the autumn equinox is traditionally called the Harvest Moon. In most years it is the September moon, but sometimes it is in October. The equinox this year happens on Sunday, September 22, so this week we have a Harvest Moon.

The Harvest Moon seems to be the only full moon given the same name by both the English and by many Native Americans of eastern and northern North America. Native American diet staples were corn, pumpkins, squash, beans, and wild rice, and all of them would typically be ready by this full moon (though, obviously, this varied by tribe and location). The Corn Moon was another Native American name for this September Moon. The Harvest Moon is also known as the Wine Moon, the Singing Moon, the Gypsy Moon, the Barley Moon and the Elk Call Moon.

Don’t confuse the Harvest moon with the Hunter’s Moon which is a more modern nickname for the Full Moon that follows the Harvest Moon.

img-moonrise-waterAt one time, this was the peak of harvest time for farmers and a full moon afforded some extra light to continue working. Crop harvesting times are much more varied these days and adding light for night work doesn’t rely on a clear night or a Full Moon, so our Harvest Moon is more of a tradition.

By legend, people have said that the Harvest Moon sometimes appears with an orange or red tinge to it. That certainly seems autumnal and Halloween-ish. If there is any coloration of this month’s Full Moon, it is an optical illusion.

When the Moon is low in the sky, you are usually looking at it through a greater amount of atmospheric particles (including pollution) than when the moon is overhead. The atmosphere scatters the bluish component of but allows the reddish component of the light to travel a straighter path to your eyes.  Actually, all celestial bodies look orange/red when they are low in the sky.  We often portray moonlight as blue in art and that comes from the reflected white light from the sun when it is high in the sky.  Cameras are more sensitive to the color of light than the human eye.

People also often say (and you often see posts online) about this Moon being “bigger.” Another trick of the eye and sky.  Obviously, the Moon doesn’t change size and the effect is not from it approaching closer to the Earth.  Our eyes just see that low in the sky moon as larger than one that’s high in the sky. This “Moon Illusion” can be seen with any full moon.

Did you know that the full moons of September, October and November as seen from the northern hemisphere correspond to the full moons of March, April and May as seen from the southern hemisphere?