Science of the Harvest Moon

This year, the Harvest Moon rises on September 26, 2026, with peak illumination at 12:49 PM EDT. It will be visible near the planet Saturn in the evening sky.

While last October’s Harvest Moon was a “Supermoon,” this year’s is not. We did have a Supermoon in January, and we’ll see one in both November and December. Next year, in 2027, we’ll have two, in January and February.

When we talk about a Supermoon, we’re not referring to Clark Kent’s secret identity. A “super” moon occurs when a full moon coincides with the Moon’s closest point in its elliptical orbit around Earth, known as perigee. This means the Moon’s appearance in the sky is 14% to 30% larger and brighter than that of a regular full moon, not a supermoon. This is the first supermoon of 2026. Because the Moon is closer to the Earth, tides can be higher than usual. And, of course, there are the werewolves to consider.

The term “supermoon” was coined by astrologer Richard Nolle in 1979, broadly defined as either a new or full Moon that occurs when the Moon is within 90% of its closest distance to Earth.

There is also a strict definition stating that a Supermoon is the single closest New Moon and Full Moon of the year. By this definition, there can be only two of them a year – a Full Moon Supermoon and a New Moon Supermoon.

Supermoons may or may not be “Super Blue Moons,” which have nothing to do with an election year or the Rodgers and Hart song popularized by The Marcels. As I’ve explained in this article on blue moons, these occur when there are more than two full moons in the month.

Harvest Moon

The Maine Farmer’s Almanac first published “Indian” names for the full Moons in the 1930s, and these names have become widely known and used. According to this almanac, the full Moon in September was called the Corn Moon by the Algonquin tribes in what is now the northeastern USA. This was the time to harvest their staple crops: corn, pumpkins, squash, beans, and wild rice.

As the full Moon that is closest to the Autumnal Equinox (September 22, 2025), this is the Harvest Moon. The first known written use of this name in the English language – according to the Oxford English Dictionary – was in 1706.

In Europe, the names for this full Moon are the Fruit Moon, as several fruits ripen as the end of summer approaches, and the Barley Moon, derived from barley harvesting and threshing.
In China and some other Asian countries, this full Moon corresponds with the Mid-Autumn Festival, a traditional harvest festival. Other names for this festival include the Moon Festival, the Mooncake Festival (when mooncakes and moon cookies are traditionally served), and the Reunion Festival (when wives visit their parents and return to celebrate with their husbands and parents).

Is this Different from the Hunter’s Moon?

The Hunter’s Moon is typically the full moon that follows the Harvest Moon, usually occurring in October. It is named because hunters could easily track animals in the fields after the harvest. While these definitions are distinct, there can be overlap.

Every three years or so, as in the last year of 2025, the Hunter’s Moon is also known as the Harvest Moon.

Science of the Harvest Moon