August 30, 2018: The Harvest Moon;
As the seasons turn…(coming September 24th).
By Mark Narwa.
Earlier generations gave the full moon of each calendar month a name based on the behavior of plants, animals and the weather, according to that particular month. This allowed them to keep track of the passing year and to set schedules for hunting, planting and harvesting. Some examples would include the Strawberry Moon given to the full moon of June, the Wolf Moon of January, the Flower Moon of May, and the Hunter’s Moon of October.
The full moon of September is called the Harvest Moon. It attained this name from the farmers in the northern hemisphere. In the shorter daylight hours of the autumn, before artificial lighting existed, farmers needed light to gather in their crops. For several evenings, the full moon near the autumn equinox would rise in the eastern sky soon after sunset. This provided an abundance of bright moonlight in the evening, thus illuminating the fields, which helped the farmers harvest their crops.
In the northern hemisphere, the Harvest Moon is the full moon closest to the autumn equinox. The autumn equinox is one of the times in the year when the sun crosses the equator, causing day and night to be of equal length. This usually occurs between September 21 and 23, which also marks the first day of autumn in the northern hemisphere.
Depending on the year, the Harvest Moon can occur anywhere from two weeks before to two weeks after the autumn equinox. This is because a lunar year is 11 days shorter than a solar year (354 vs 365) making the full moon come 11 days earlier in the month each year. This causes the September full moon to be closer to the beginning of the month, making the October full moon closer to the beginning of October. About every three years, this makes the October full moon the Harvest Moon because of the number of days closer to the autumn equinox than the September full moon.
What sets the Harvest Moon apart from other full moons is that throughout the year, the moon rises on average 50 minutes later each day. At the autumn equinox, the full moon rises about 30 minutes later each day. The full (Harvest) moon rises at sunset and then very close to sunset for the next 4 nights, making it almost appear as if there are full moons several nights in a row.
As with every full moon near the horizon, the Harvest Moon will appear larger than normal and a bright orange colour for several days.
This year, the Harvest Moon is September 24 at 10:52 pm, just two days after the autumn equinox.