A Smaller Than Usual Blue Moon Will End the Month With a Lunar Spectacle. Here's What to Know About the Full Micromoon
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2Feb%2F05%2Feb05fdf6-6502-41b2-99d1-66d081657aed%2Fblue_moon__19549135223.jpg&w=1024)
A blue moon will occur on May 31, marking the second full moon of the month. This particular blue moon will be classified as a micromoon, appearing smaller and dimmer than usual due to its distance from Earth. While the event is interesting, the differences may be subtle enough to go unnoticed by most observers.
- ▪The blue moon is the second full moon in May, a phenomenon that occurs approximately every two and a half years.
- ▪This blue moon will be the smallest full moon of 2026, appearing about 6 percent smaller and 10 percent dimmer than an average full moon.
- ▪The term 'blue moon' gained popularity in the 1980s due to a misunderstanding from a 1946 magazine article.
Opening excerpt (first ~120 words) tap to expand
A Smaller Than Usual Blue Moon Will End the Month With a Lunar Spectacle. Here’s What to Know About the Full Micromoon The blue moon will be the second of two full moons in the same month, a coincidence that only takes place about every two and a half years. It will also appear to be slightly smaller and dimmer than the average full moon Margherita Bassi | Daily Correspondent May 28, 2026 3:40 p.m. ShareCopy linkEmailSMSFacebookXRedditLinkedInBlueskyPrintAdd as preferred source A blue moon in 2015 Tatters ✾ from Brisbane, Australia via Wikimedia Commons under CC BY-SA 2.0 This year, May is bookended by two full moons. So, on Sunday, the month’s closing spectacle will be a once-in-a-blue-moon event—literally.
…
Excerpt limited to ~120 words for fair-use compliance. The full article is at Smithsonian Magazine.
Discussion
0 commentsMore from Smithsonian Magazine
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2F03%2F1f%2F031f1c20-fb8c-45e8-964a-4ba82e2950d8%2Fs-014-c01_1.jpeg&w=320)
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2F21%2F3e%2F213e6ee0-ae4b-403e-a75e-516653c10772%2Fgettyimages-139289970.jpg&w=320)
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2F88%2F59%2F885977a1-c31a-42e2-8ac9-c39bebe9ded5%2Ferdos4.jpg&w=320)
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2F27%2Faa%2F27aa2593-9660-43a6-844d-52af3a7fd996%2Fc69a7443_1.jpg&w=320)
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2F3f%2F59%2F3f59f4a3-baa6-4e76-8ec1-d1f67bed20b5%2Felisenda.jpg&w=320)
%2Fhttps%3A%2F%2Ftf-cmsv2-smithsonianmag-media.s3.amazonaws.com%2Ffiler_public%2F21%2Fe0%2F21e01f01-f286-4f57-bc46-5d031b7f727f%2Fenterprise12.jpg&w=320)