Once In A Blue Moon Happens This May — Literally

CALIFORNIA, Md. — Skywatchers will have a rare reason to look up at the night sky this month as May 2026 delivers an unusual celestial double feature — two full moons in a single month, ending with a rare Blue Moon on May 31.

According to the Maryland Department of Natural Resources’ recent Facebook post, May began with a full Flower Moon on May 1 and will close with another full moon on May 31, creating what astronomers call a “Blue Moon.” The term refers to the second full moon occurring within the same calendar month — an event that only happens every few years.

The Blue Moon will reach peak illumination at approximately 4:46 a.m. EDT on May 31 as it sets below the horizon, before rising again later that evening at 9:16 p.m., according to the Maryland DNR celestial report.

Flower Moon (May 1, 2026)

The Flower Moon, the traditional name for May’s full moon, marks a seasonal turning point as spring reaches its peak. Named for the abundance of blooming flowers across North America, it reflects a time of growth, renewal and natural beauty. The moon has long symbolized fertility and new beginnings, aligning with longer days, warmer temperatures and the flourishing of life. It is often associated with reflection, celebration of progress and embracing the energy of the season ahead.

Blue Moon (May 31, 2026)

The Blue Moon refers to the second full moon occurring within a single calendar month — a rare event that happens only every few years. Despite its name, the moon does not appear blue; instead, the term highlights its uncommon timing. The rarity of the event gave rise to the phrase “once in a blue moon,” used to describe something that seldom occurs. This year’s Blue Moon on May 31 serves as a striking close to the month, offering skywatchers an unusual opportunity to witness two full moons in one cycle.

Astronomers note that Blue Moons typically occur about once every two to three years because the lunar cycle lasts roughly 29.5 days, allowing an “extra” full moon to occasionally fit within a single month.

Adding to the uniqueness of this month’s skies, the new moon will occur on May 16, creating darker nighttime conditions ideal for stargazing and viewing deep-sky objects.

The May 31 Blue Moon is also considered a “micromoon,” according to Live Science, meaning the moon will appear slightly smaller and dimmer than usual because it occurs when the moon is farther from Earth in its orbit. While the size difference is subtle to the naked eye, astronomers say the event still offers a striking opportunity for skywatchers and photographers alike.

The last Blue Moon occurred in August 2024, and the next one is not expected until December 2028.

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