A rare blue micromoon rose over the Temple of Poseidon at Cape Sounion, Greece, on Sunday, May 31, 2026 [3], [4].
This astronomical event is significant because it combined two rare lunar characteristics, a blue moon and a micromoon, while coinciding with the seasonal transition at the end of spring in the Northern Hemisphere [1], [2].
A blue moon occurs when a second full moon appears within a single calendar month [1]. In this instance, May 2026 featured two full moons, with the second occurring on May 31 [1].
Simultaneously, the moon was classified as a micromoon because it was near apogee, the point in its orbit farthest from Earth [2]. This positioning resulted in the smallest full moon of 2026 [2].
Skywatchers worldwide captured images of the event, but the sighting at the historic Temple of Poseidon provided a distinct backdrop for the lunar rise [1], [4]. The event was reported across multiple global locations, including New Delhi, India [4].
While most reports confirm the May date, some conflicting data suggests a similar event in August. However, the primary lunar cycle for the micromoon occurred during the May window [1], [2].
“A rare blue micromoon rose over the Temple of Poseidon at Cape Sounion, Greece.”
The occurrence of a blue micromoon is a convergence of orbital geometry and the Gregorian calendar. While 'blue moon' is a popular term for the second full moon in a month, the 'micromoon' aspect is a physical result of the moon's elliptical orbit. When the moon is at apogee, it appears smaller and dimmer than a supermoon, providing a stark contrast in scale for astronomers and photographers.
