Lucky skygazers will be able to witness two celestial events on May 5, 2023. We will see a full moon—which is dubbed the “flower moon”—as well as a penumbral lunar eclipse. Here’s everything you need to know about the special coincidence.
What is the flower moon?
The flower moon is simply the full moon that occurs in the month of May. North American folklore mentions the full moon’s appearance at the height of spring, when wildflowers begin to bloom, trees unfurl their leaves, and pollinators like butterflies and moths start feeding on the plants’ nectar. Indigenous peoples have their own nicknames for May’s full moon—the Creek and Choctaw call it the mulberry moon, referencing the berry native to the southeastern U.S., and tribes in the Pacific Northwest have called it “camas blooming time.” Camas—a flowering plant with a bulb that looks like an onion—is a traditional food harvested from April through June [PDF].
This year’s flower moon will be especially memorable because it coincides with a penumbral lunar eclipse. On the night of May 5, Earth will align between the sun and the moon, putting the moon in Earth’s shadow. Penumbral lunar eclipses are subtle and not as easily seen as solar eclipses, but this one will be visible to everyone on the dark side of Earth.
When to See the Flower Moon and Penumbral Lunar Eclipse
To catch 2023’s full flower moon and penumbral lunar eclipse, look skyward on Friday, May 5. The penumbral eclipse begins at 11:14 a.m. EDT and lasts about four hours. While it won’t be visible North and South America (except for Hawaii) because the moon will be below the horizon, the eclipse will be seen in Europe, Africa, Asia, and Australia.
A version of this article was originally published in 2019 and has been updated for 2023.