Flower Moon 2023: A rare type of full ‘blue moon’ is here, and it’s also a ‘flower moon’

May’s full moon rises tonight (May 5), offering skywatchers the chance to experience the colorfully named “Flower Moon” of 2023.

During the full moon, the lunar face will be fully illuminated by the sun with the Flower Moon visible for most of the night across the globe from around sunset. From New York City, the Flower Moon will rise at around 6:59 p.m. EDT (2259 GMT) and will set at around 5:39 a.m. EDT (0939 GMT) the following morning. At the exact moment of the full moon around 1:36 a.m. EDT (0536 GMT) when it is 180 degrees from the line the sun traces in the sky, the Flower Moon will be in the Libra constellation, according to In the Sky (opens in new tab).

Friday will be an interesting day for moonwatchers, as it also marks a penumbral lunar eclipse, though according to In the Sky this will not be visible from New York City as the moon will be below the horizon for the entire time the moon is in the shadow of the Earth.

Penumbral eclipses happen when the Earth passes between the moon and the sun with the three celestial objects aligned with our planet in the middle. As a result, the shadow of our planet falls on the lunar face, obscuring it from the light of the sun.

During a penumbral eclipse, the moon only moves into the penumbra, the lighter outer region of the Earth’s shadow, meaning our planet appears to obscure part of the sun’s disk but not all of it. Thus, the moon receives some light but is slightly dimmed. The resulting effect can be so subtle that it is barely perceptible, sometimes only visible to people with very good eyesight or in carefully controlled photographs.

The Flower Moon will, fortunately, be more conspicuous and visible beyond the regions of Earth that get to experience the penumbral eclipse.

The monthly full moons all receive specific monikers many of which come from Native American sources, according to Farmer’s Almanac. (opens in new tab) The May full moon’s title the Flower Moon relates to flowers spring forth across North America during the month of May.

In the tradition of Native American naming, it’s commonly known as the flower moon, to reflect the spring blooms seen this month. Other names for the May full moon include the hare moon, the corn-planting moon and the milk moon.

According to some Native tribes, the full flower moon means increasing fertility, as temperatures become warm enough for animals to bear young.

For this reason, it’s sometimes called Mother’s moon. It also signals the near end of late frosts.

The name flower moon is sometimes used to describe the full moon of June, but a more popular name for June’s moon is the strawberry moon.

May Moon Names

Frog Moon (Cree). Ponies shed (Sioux). Bright moon (Celtic). Waiting Moon (Hopi). Mulberry Moon (Greek). Ninth Moon (Wishram). Idle Moon (Assiniboine). Big Leaf Moon (Mohawk). Panther Moon (Choctaw). Grass Moon (Neo-Pagan). Planting Moon (Cherokee). Corn Planting Moon (Taos). Little Corn Moon (Natchez). Green Leaf Moon (Apache). Corn Weed Moon(Agonquin). Field Maker Moon (Abernaki). Blossom Moon (Anishnaabe). Shaggy Hair Moon (Arapaho). Green Leaves Moon (Dakota). Fat Horses Moon (Cheyenne).

Leaf Tender Moon (San Juan). Hare Moon (Medieval English). Milk Moon (Colonial American). Strawberry Moon (Potawatomi). Hoeing Corn Moon (Winnebago). Alewive Moon (Passamaquoddy). Ninth Moon (Dark Janic), Mothers Moon (Full Janic). Flower Moon, Corn Plant Moon, Milk Moon (Algonquin).