A rare blue micromoon illuminated the sky over the Temple of Poseidon at Cape Sounion and other global locations on May 31, 2026 [1].
This astronomical event is significant because it combines two uncommon lunar conditions: a "blue moon," which is the second full moon in a single calendar month, and a "micromoon," which occurs when the moon is at its farthest point from Earth [2].
Skywatchers across the world observed the event, with notable sightings reported over Greece and in New Delhi, India [1, 3]. The moon reached its peak on May 31 at 4:45 a.m. ET [1]. Because the moon was at its most distant point in its orbit for the year, it appeared smaller than a typical full moon [1].
The event served as a celestial marker for the end of spring [2]. A blue moon does not actually change the color of the moon; it is a naming convention for the timing of the lunar cycle [2]. In this instance, the moon was the second full moon of May 2026 [2].
Observers at Cape Sounion witnessed the moon rising over the ancient Temple of Poseidon, creating a visual contrast between the prehistoric architecture and the rare lunar alignment [1, 2]. The visibility of the micromoon in diverse geographic locations, from the Mediterranean coast to South Asia, highlighted the global nature of the event [3].
“The smallest, most distant full moon of 2026 lit up the sky over the Temple of Poseidon.”
The occurrence of a blue micromoon is a convergence of orbital geometry and the Gregorian calendar. While a supermoon occurs at perigee (the closest point to Earth), a micromoon occurs at apogee. This event underscores the variance in the moon's elliptical orbit, resulting in a visually smaller lunar disk during a month that already featured an extra full moon.
