Everything You Need to Know About August 2024's Full, Blue Supermoon

The Moon has captured the attention of people since before recorded history. We’ve built calendars and mythologies around its cycles, and we imagine an increase in monsters and madness when it’s full. Even in our modern scientific era, every full Moon carries a certain amount of magic with it, but the August 2024 full Moon is extra special.

When compared with a more conventional full Moon, this one will appear almost as if the Moon is bearing down on the Earth. While it might seem like the opening act to Roland Emmerich’s 2022 space-based disaster flick Moonfall (streaming now on SYFY), it’s actually a blue Moon, supermoon, and full Moon all at once.

What is a blue Moon?

NASA Image of the Full moon Photo: NASA

You’ve probably heard the phrase “once in a blue Moon,” referring to something which is moderately uncommon. The idea of blue Moons dates back to the mid-16th Century and may have referred to rare atmospheric events where smoke or other debris makes the Moon appear blue. It may also refer to an old English phrase meaning “betrayer Moon,” because a blue Moon sometimes led to mistakes in timekeeping.

That’s because both definitions of a blue Moon refer to an extra full Moon within a given period. The Moon’s cycle takes roughly a month (29.5 days), so there is only one per month on average, and three per season. Sometimes though, because the Moon’s cycle is a little shorter than a month, you get an extra one a season or calendar month. Historically, a blue Moon referred to the third full Moon in a season which contains four full Moons. Beginning in the 1940s, the term began to refer to a second full Moon in a calendar month.

Because the Moon’s cycle takes just short of a month and the August 2024 full Moon peaks on the 19th, then we know that this blue Moon is the third of the season.

What is a supermoon?

The term "supermoon" was coined by astrologer Richard Nolle in 1979. He defined it as any full Moon which occurs when the Moon is at least 90% of the way toward its closest approach with Earth (perigee). See, the Moon’s orbit isn’t totally circular. It’s squishy, and the Moon appears larger or smaller, depending on where it is in its orbit.

At its farthest point, the Moon is about 251,000 miles from Earth. At its nearest, it’s only 224,000 miles away. As a result, the Moon covers more or less of the night sky, between 0.5 and 0.6 degrees of arc (30 - 36 arc minutes). Because the Moon is so much closer during a supermoon, the full Moon can appear up to 14% larger and 30% brighter. When it comes to full Moon’s, a supermoon is the best show in town. August’s full Moon is the first of four consecutive supermoons. If you miss this one, you’ll have a chance to see a few more through the rest of the year.

How to See the August 2024 Super Blue Moon

It’s been about a week since the Perseids meteor shower peaked, but there’s still plenty to see in the night sky. The August 2024 full Moon peaks August 19, 2024, at 2:26 p.m. ET. A couple days later, a shadow will creep over the horizon and the Moon’s phase will transition to a waning gibbous.

While the full Moon technically only lasts for a single day, the Moon appears full for about three days, surrounding the peak. If you look to the sky anytime between now and Tuesday evening, you’ll see the full, blue supermoon staring back at you.

Catch the supermoon in a sky near you! And catch Moonfall streaming on SYFY.