MGA Faculty Q&A: The Blue Moon Isn’t Blue & Other Things To Know About This Week’s Celestial Event

Author: News Bureau
Posted: Tuesday, August 29, 2023 12:00 AM
Categories: Pressroom | Faculty/Staff | School of Health and Natural Sciences

Macon, GA

Image: Peter Alfred Hess from United States via Wikimedia Commons.

If cloud conditions allow it, we’ll be able to see a rare(ish) blue moon on Wednesday night (8/30). It will reach its peak at 9:36 p.m. EDT. To learn more about this celestial event, we turned to Dr. Lawrence Camarota of Middle Georgia State’s Department of Natural Sciences.

What exactly is a blue moon and why are people calling this upcoming one “super?”

There are two slightly different definitions of a blue moon. The original definition was the third full moon in a season that has four. The modern version is the second full moon in a calendar month. This upcoming full moon is a blue moon by the modern definition. A super moon is a full moon that occurs when the moon is near the closest point in its orbit to the Earth, and so appears slightly bigger than usual. A 'super blue' moon is a moon that satisfies both conditions.

So blue moons aren’t actually blue. Why are they called that?

Historically, every full moon has a name, based on when it occurs in a season. The full moons of winter are Wolf, Snow, and Worm; spring moons are Pink, Flower, and Strawberry, etc. However, the lunar cycle is 29.5 days long, so some years have 13 full moons in them, meaning that every two or three years there is an extra full moon, and that full moon gets the name Blue.

How often do super blue moons occur?

Over a long time scale, a super blue moon should occur approximately once per 20 years, however the time between successive super blue moons can vary wildly.

Any tips on the best way to observe a blue moon?

Full moons are a relatively easy phenomenon to observe; you can see them with your eye as long as there is no clouds blocking the way, and this one will be in the sky from sundown to sunup. Unfortunately for us in Central Georgia, Wednesday night from sundown to sunup is when we are expecting the heaviest clouds from Hurricane Idalia.

When is the next super blue moon?

The next super blue moon won't be until 2037, but by an astonishing coincidence there will be two that year, in January and March. This happens because February is slightly shorter than the lunar cycle, so February 2037 will have no full moons, and January and March of that year will have two each, both of which occur when the moon is close enough to count as a supermoon.

Dr. Lawrence Camarota graduated with a B.S. in physics and a B.S. in aerospace engineering from the University of Florida. He earned a Ph.D. in physics with a focus on astronomy from the University of Arizona. He is a member of the American Association of Physics Teachers, the Royal Astronomical Society, and the Friends Society. His areas of interest are astrophysics, cosmology, electronics, and wavelets.