What Is a Blue Moon? | Different Types of Full Moons

Who doesn’t love to stare up at a brightly lit night sky? When there’s an absence of light pollution, it’s one of the most beautiful sights to see. 

Full moons roll around about every 29.5 days, with each lunar cycle lasting that long. But, with 30 to 31 days in each calendar month, occasionally, an additional full moon pops up within the calendar cycle. When that happens, we’re gifted with a Blue Moon. 

What is a Blue Moon?

It’s no surprise the saying, “Once in a blue moon,” refers to something’s rarity. When it comes to astronomy, a Blue Moon is quite rare because it's an additional full moon that occurs within a specific cycle. There are two different cycles within the lunar and calendar cycles that cause this magnificent display.