What Is a Blue Moon? One’s Coming in August

Most of us have heard the phrase “once in a blue moon,” and we recognize that it means something that only happens once in a great while. Actually, a blue moon only occurs about seven times every nineteen years, so “once in a blue moon” is actually rarer than most people think. Maybe you’ve never even seen one—but now is your chance. One is coming this month!

On August 30th, 2023, we’ll have a full blue moon that will also be the largest supermoon of the year.

But, what exactly is a blue moon, other than something that doesn’t happen often?

People use the term blue moon to describe a situation in which we have two full moons in the same month. While you might think that happens all the time, clearly, it’s a rarity.

Ironically, blue moons aren’t any different color. The moon itself is still gray. The phrase originated in the 16th century when people would often say “the moon is blue,” when discussing something that couldn’t possibly happen.

When the moon is a bit closer, it might appear to have a bluish tint, but that’s only because of haze, dust, and other particles floating through the atmosphere. The color of the moon itself doesn’t change.

Speaking of the moon being closer, this month’s blue moon is extra rare because it’s also a supermoon. Supermoons only happen 3-4 times a year, so while they aren’t as rare as blue moons, they are still an incredible sight to behold!

Supermoons naturally appear bigger and brighter because they coincide with the time when the moon’s orbit is closest to the earth. This August’s blue supermoon is special because it will be the closest supermoon of the year. August has already been an astronomer’s dream, thanks to the sturgeon moon that appeared earlier in the month.

You don’t have to be an astronomer or even someone typically interested in space to recognize that this phenomenon is something that shouldn’t be missed! Make sure you mark your calendars for August 30th and have a clear view of the horizon. If possible, head to a place that is away from as much light pollution as possible. And, if you have access to a telescope, now is the time to use it!

The moon will rise at sunset, so you won’t have to wait long to see this incredible spectacle that only happens “once in a blue moon.”