An event that occurs once in a blue moon is coming up on the final day of May. The second full moon of the month will be on May 31 and is known as the blue moon. It follows a dazzling flower moon that ...

A rare Blue Full Moon is set to grace the night sky, offering sky-gazers an unusual lunar spectacle that will not be seen again in quite the same way for decades. The celestial event is attracting ...

Mark May 31, 2026, in your calendar because there will be a rare blue moon in Sagittarius. Blue moons occur when there's a second full moon toward the end of the month. This is an ultra-powerful ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. A full Blue Moon is coming this weekend — and despite the ...

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You’ve probably heard the phrase “once in a blue moon” used to describe something that happens rarely — and that makes sense, given that a blue moon usually refers to the second full moon to hit in ...