What Is a Full Moon? Names, Dates & Meanings

Quick Answer

A Full Moon occurs when Earth sits directly between the sun and the moon, causing the entire sunlit face of the moon to be visible from Earth. Full Moons happen approximately once every 29.5 days — one per month — and are the brightest, most visible phase of the lunar cycle.

What Causes a Full Moon?

During a Full Moon, the moon is at "opposition" — on the opposite side of Earth from the sun. Sunlight strikes the entire face of the moon that faces Earth, illuminating it fully. The moon rises around sunset and sets around sunrise, making it visible for much of the night.

A Full Moon is not the same as a lunar eclipse, even though both require a near-alignment of the sun, Earth, and moon. During a regular Full Moon, the alignment is approximate and the moon passes above or below Earth's shadow. A lunar eclipse only occurs when the alignment is nearly perfect and the moon passes directly through Earth's shadow — a much rarer event.

The 12 Named Full Moons

Each Full Moon of the year carries a traditional name rooted in Native American, Colonial American, and European farming traditions. These names reflect seasonal markers that were once critical for survival:

• January — Wolf Moon: Named for the howling wolves heard near villages in winter.
• February — Snow Moon: The heaviest snowfall of the year typically falls in February.
• March — Worm Moon: Earthworms emerge as the ground thaws, signaling the return of robins.
• April — Pink Moon: Named for the wild ground phlox (pink flowers) that bloom in spring.
• May — Flower Moon: Flowers are in full bloom across North America.
• June — Strawberry Moon: The short strawberry harvesting season peaks in June.
• July — Buck Moon: Male deer (bucks) begin regrowing their antlers in velvet.
• August — Sturgeon Moon: Sturgeon fish were traditionally most abundant in the Great Lakes.
• September — Harvest Moon: The full moon closest to the autumnal equinox, providing extra light for harvest.
• October — Hunter's Moon: Hunters used the bright moon to spot prey in cleared fields after harvest.
• November — Beaver Moon: Time to set beaver traps before waterways froze.
• December — Cold Moon: Long, dark winter nights begin in earnest.

The Harvest Moon — Why It's Special

The Harvest Moon is the Full Moon closest to the autumnal equinox, usually in September (occasionally early October). What makes it extraordinary is that for several consecutive nights around this Full Moon, the moon rises only 20–30 minutes later each night instead of the usual 50 minutes. This provides extended natural illumination at dusk — historically critical for farmers working late into the evening to bring in crops before winter.

The Hunter's Moon follows in October and has a similar characteristic, rising early enough to light the fields for hunters tracking game across the cleared harvest fields.

Blue Moons, Supermoons, and Blood Moons

A Blue Moon occurs when there are two Full Moons in a single calendar month, or when a season contains four Full Moons (making the third one the "Blue Moon"). This happens roughly every 2.5 years — hence the expression "once in a blue moon."

A Supermoon occurs when a Full Moon coincides with the moon's closest point to Earth (perigee), making it appear up to 14% larger and 30% brighter than a typical Full Moon. A Blood Moon is the reddish-orange moon seen during a total lunar eclipse — sunlight bending through Earth's atmosphere paints the moon with the color of all Earth's sunrises and sunsets at once.

Frequently Asked Questions