May 31 blue moon punctuates 13 full moons in 2026

Technology May 23, 2026

Heads up, skywatchers! A rare blue moon is coming on May 31, marking the second full moon in a single month.
This doesn't happen often: 2026 actually gets 13 full moons instead of the usual 12.
The first one, called the flower moon, showed up on May 1 and kicked off this unusual lunar lineup.

Blue moon from lunar cycle mismatch

A blue moon happens when the lunar cycle (about 29.5 days) doesn't quite sync with our calendar months, letting two full moons squeeze into one month.
The flower moon gets its name from spring's blooms.
If you want to catch this rare sight, look east near Virgo on May 31.
It's a cool moment for anyone who loves stargazing or just wants to see something special in the night sky.