The next full moon will take place early this weekend. The moon reaches full illumination early Saturday, Sept. 10. This moon won’t be a “supermoon” like the last four full moons. It will, however, illuminate the night sky for several nights and appear full to the naked eye for about three days.
What is the September full moon called?
The September full moon has many names, but the main label is the “harvest moon.” The harvest moon is the name of the full moon occurring closest to the autumnal equinox, or the first day of autumn. It usually occurs in September but occasionally will take until early October to arrive.
According to NASA, the first time a full moon was referred to as the “harvest moon” in English was 1706. As the name implies, it has to do with the harvesting of crops as the colder months approach. Many farmers worked late into the evening and, before the invention of artificial light, the illumination of the full moon helped them see what they were doing and provided a little extra work time.
NASA reports other names include the fruit moon, because a lot of fruit trees are baring ripe fruit, and the barley moon, because this is the time of year a lot of farmers harvested their barley crops.
The Algonquin native American tribe had a similar, harvest-themed name for the moon. NASA says records in the Maine Farmer’s Almanac show the northeastern U.S. tribe called the September full moon the “corn moon.” As you can imagine, it is because corn crops are ripening and that was a staple in their diet.
When can you see the September full “harvest” moon?
The full “harvest” moon will occur at 5:59 a.m. Saturday. At that time, the moon will be in the process of setting. It will set in the west-southwest sky at 6:57 a.m. Sept. 10.
Even though the exact time of full illumination is Saturday, it will appear bright and nearly full for around three days. The Friday night moonrise will occur in the east-southeastern sky at 7:47 p.m. Friday with the moon appearing nearly full at that time. The moon will return Saturday evening and still look mostly full to the naked eye. It will rise in the eastern sky at 8:12 p.m. and sets Sunday morning at 8:10.
Why isn’t this full moon a “supermoon”?
NASA defines a supermoon as a full moon occurring at the same time as the moon’s perigee. The perigee is the closest point of the moon’s orbit with the earth. The moon takes about 27 days to orbit the earth. During each 27-day cycle is a perigee, or point where the moon is closest to the earth, and an apogee, or point where the moon is farthest from the Earth.
To be considered a “supermoon,” the full moon has to occur when the moon is within 90% of its perigee. In the current lunar cycle, perigee was reached on Wednesday, Sept. 7. This full moon is occurring two days and fifteen hours after the perigee. The moon will be outside of the 90% window at that time so it will not be considered a “supermoon.” NASA says roughly three to four supermoons occur each year and they usually happen back-to-back. When a full moon occurs during the moon’s perigee or closest point, the moon will appear about 17% bigger and about 30% brighter. Below is a list of all 14 perigees occurring in 2022. The notation “(S)” indicates the perigees that occurred close enough to the full moon to result in a “supermoon.”