when to see the blue supermoon

The next blue supermoon will occur on May 31, 2026. This blue moon is considered a supermoon because it happens near the moon's closest point to Earth (perigee), making it appear larger and brighter than usual. There will be no blue supermoon in 2025; the next one after that is in 2026. A blue moon is defined as the second full moon in a calendar month or, in a seasonal definition, the third full moon in a season of four full moons. Supermoons, on the other hand, happen when the moon is at its closest to Earth during a full moon phase, appearing larger and brighter. Thus, the blue supermoon is rare because it combines these two phenomena. The May 31, 2026 blue supermoon will be observable at night, with the moon fully illuminated around that date.