HOUSTON – Wednesday night’s full moon will be spectacular for a number of reasons. It will appear bigger and brighter. We’ll have clear skies in Southeast Texas. And it has a unique name, Super Blue Moon. But how rare is it?
The moon isn’t blue:
The earliest occurrence of the moon being called “blue” was after the eruption of Krakatoa in 1883. The volcanic ash was said to have turned the moon blue color. But today, using the term “blue moon” is about the rarity of the event.
Blue Moon:
First, we have to understand definitions. A blue moon is a full moon that occurs twice in one month. As the saying goes, “That happens once in a blue moon,” meaning it’s a rare event. Blue moons occur once every two or three years so they aren’t that rare. The moon travels around the Earth once every 29.5 days so if a full moon occurs at the beginning of the month, a second will follow at the end. But that hasn’t always been the definition. The first use of the words “blue moon” was found in 1937. But it referred to the fourth full moon in a season. Still not terribly rare but not common either.
Supermoon:
A “supermoon” is defined as the moon reaching its complete phase at perigee. Perigee is the closest point of the moon to the Earth in its rotation. The moon travels around the Earth in an elliptical orbit, not a perfect circle. This creates a near point and a far point. If the moon is within 90% of this closest point it, is considered a supermoon.
Between 1900 and 2050, the moon has reached full phase close enough to perigee 19 times, or an average of once about every eight years, which, again, isn’t all that rare.
Super Blue Moon:
It can occur as often as once every five years or have a gap as far as 14 years. The last super blue moon occurred Wednesday, January 1, 2018. The next will occur Saturday, January 1, 2037. Being closer to Earth makes the moon appear 14% larger and 30% bigger. This is more noticeable low on the horizon close to moon rise.
The irony:
The term supermoon isn’t a scientific term. Astrologer Richard Nolle coined the term in 1979. Since then, the name has been accepted by the scientific community.
We’d love to see your pictures of the Super Blue Moon. Please share them with us on Click2Pins or tag me at @kprc2anthony on Facebook, Instagram or X.
