Indonesia Arrivals The Blue Moon Phenomenon On August 22

The Blue Moon phenomenon will decorate the Indonesian sky on August 22. (photo: Blue Moon Alexander Andrews / Unsplash.)

JAKARTA - This week, Indonesia is back with a unique natural phenomenon. Dubbed the Blue Moon, this phenomenon will be observed throughout Indonesia on Sunday, August 22, 2021.

"This time the Blue Moon can be seen throughout Indonesia from sunset to before sunrise the next morning," said researcher from the Center for Space Science of the National Institute of Aeronautics and Space (LAPAN) Andi Pangerang, Friday, August 20.

In his statement, Andi explained how the phenomenon could be dubbed the Blue Moon. In general, there are two different definitions of the Blue Moon. Such as the Seasonal Blue Moon, which is the third Full Moon of one of the astronomical seasons in which there are four Full Moons.

While the second is the Monthly Blue Moon, which is the second Full Moon of one of the months in the Gregorian calendar in which there are two Full Moons.

"The full moon on August 22 is included in the Seasonal Blue Moon. In the Maine Farmers' Almanac in the United States (USA), this full moon is called the Sturgeon Full Moon because in August, Sturgeon fish (caviar-producing fish) emerges to the surface of the lake so it is easy to catch ," explained Andy.

This full moon also has other names, namely Green Corn Moon, Black Cherry Moon and Flying Up Moon.

Andi said that the Seasonal Blue Moon occurs every two or three years, previously on May 19, 2019 and May 22, 2016. This phenomenon will occur again on August 20, 2024 and May 20, 2027.

The Monthly Blue Moon also occurs every two or three years, previously on July 31, 2015 and January 31, 2018. This phenomenon will occur again on August 31, 2023 and May 31, 2026.

Why is it called the Blue Moon?

Blue Moon is not actually blue. Andi explained the historical origin of this term and the two definitions are actually still confusing. Most people consider it a misinterpretation.

Many people believe the term Blue Moon which is interpreted as something that happens very rarely comes from when the smog and volcanic ash from volcanic eruptions turn the Moon into a bluish color.

This term has been around for at least 400 years from the current search, in which a Canadian folklore speaker, Dr. Philip Hiscock, suggested that the mention of the Blue Moon means that something is odd and will never happen.

Why Can a Bule Moon Happen?

According to Andi, generally, in an astronomical season (which is marked by solstices or equinoxes) there can be three full moons. This is because the season duration for autumn (northern hemisphere) and winter (northern hemisphere) is on average 89.5 days, while the season duration for spring (northern hemisphere) and summer (northern hemisphere) is an average of 93 days.

While the average settlement (one cycle of the Moon's synodic period around the Earth) is 29.53 days. So that 89.5 : 29.53 = 3.03 or rounded up to 3. However, if the first Full Moon occurs close to the start of the astronomical season, it is possible in an astronomical season to occur four Full Moons. The third full moon in an astronomical season that experiences four full moons is known as a blue moon.

In the Gregorian calendar, there are seven months that are 31 days old and there are four months that are 30 days old. This value is greater than the average repayment of 29.53 days. If the Full Moon occurs around the beginning of the Gregorian month, then it is possible in a month in the Gregorian calendar to have two full moons. The second Full Moon in a month in the Gregorian calendar is also known as the Blue Moon.