On May 31, 2026, Earth Will Have A Blue Micromoon: Here's What That Means

Summary: Mark your calendars for May 31, 2026, when the night sky will feature a rare "Blue Micromoon." A micromoon happens when a full moon is at its farthest point from Earth (apogee), making it look smaller and dimmer than usual. A blue moon is simply the second full moon in a single calendar month, which happens because the 29.5-day lunar cycle doesn't perfectly match our calendar.

Don't expect it to actually look blue, though! The name likely comes from an old word meaning "to betray," because an extra full moon tricked people trying to track the seasons. The only time the moon actually turned blue was after a massive volcano erupted in 1883!

For more details, see rssapp-iflscience-com at iflscience.com/may-2026-is-about-to-see-a-blue-moon-thats-also-a-micromoon-a-super-rare-double-bill-is-set-to-hit-the-night-sky-83631 (opens in new tab)