Two full moons in October
As 2020 progresses with more uncanny events, major celestial occurrences through the year can be attributed to the overall atmosphere of 2020. According to the National Aeronautics and Space Administration (NASA) and the Old Farmer’s Almanac, this year, there will be a total of 13 full moons as opposed to the typical 12 full moons that occur in the lunar year. The occurrence of an extra moon occurs specifically in October of 2020 where the lunar cycle falls nicely into place so that two full moons happen to appear in this calendar month. The first full moon of the month occured on October 1 and is called the Harvest Moon and the second full moon occured on October 31 and is called the Blue Hunter’s Moon.
The Harvest Moon usually occurs in September after the Autumn Equinox or the first day of Autumn. However, due to the official harvest season and crop yield, this year’s Harvest Moon was moved to Thursday, October 1 where the moon rose to its peak at 4:05 p.m. EST. The celebration of the Harvest Moon refers to a time when the brightness and luminosity of the moon becomes so great that farmers are able to use the moon’s light in order to harvest their crop during the night and store their harvests for the coming winter. This also refers to a time of lunar celebrations as a Harvest Full Moon is widely celebrated in different cultures.
Commonly known as a Blue Moon, this year’s Blue Hunter’s Moon occured on Saturday, October 31 rising to its peak at 10:49 AM EDT. That’s right, on Halloween. Additionally, this year’s phenomenal Blue Moon is even more unique as this year’s Blue Hunter’s Moon appears across all time zones for the first time in 30 years which is a rare occurrence.
Today, the most common definition of a Blue Moon, often referred to as a Calendrical Blue Moon, is when there happens to be two full moons in one calendar month, where the second full moon is called a Blue Moon.
“It takes our Moon about 29.5 days to complete one cycle of phases (from new Moon to new Moon),” Astronomer Bob Berman from the Old Farmer’s Almanac said. “So if a full Moon occurs on the first of a month, there will be a second full Moon—a Blue Moon—at the end of the month, too (except in February).”
Additionally, according to NASA, a calendrical Blue Moon occurs every two and a half to three years.
This year’s Blue Moon will also be known as the Hunter’s Moon. This full moon is typically marked after the Harvest Moon and is a time when hunters hunt their game in order to store meat for the coming winter.
Apart from the calendrical blue moon, there is a more traditional approach to marking the occasion of blue moons.
Typically defined as a Seasonal Blue Moon, is when “[one] season—defined by the dates of the solstices and equinoxes—typically has three full moons occur within it,” Berman said. “If a season instead has four full moons, then the third full moon (not the fourth) in the season may be called a Blue Moon.”
A seasonal blue moon occurs every 2 to 3 years on average.
Under usual circumstances, blue moons do not actually appear blue as this phenomenon only occurs after a volcanic eruption or extremely severe forest fires.
Usually at sunset, a typical full moon initially appears red due to the shift in light allowing for aerosols in the atmosphere to become more prevalent. The aerosols in the air act as a red light filter blocking out blue light and allowing for red light to pass through thus making the moon appear red, according to space.com. This makes the sky and rising moon appear more of a reddish color.
In the same way, the phenomenon of a blue-colored full moon is due to the smoke released into the atmosphere from a volcanic eruption or intense wildfire in which the smoke acts as a blue light filter blocking out red light only allowing blue light to pass through thus making the moon appear blue.
The next seasonal Blue Moon is predicted to occur on August 21, 2021 and the next calendrical Blue Moon is predicted to occur on August 30, 2023 according to the Old Farmer’s Almanac.