This week's full moon happens only once every 3 years

September's full moon sets the stage for a Halloween blue moon.

The full moon shines over trees.
(Image credit: Shutterstock)

This week, for the first time in three years, the September full moon is in a unique situation: it's happening so early in the month — a timing that gives it an entirely different name, the corn moon, instead of the harvest moon — that it sets the stage for October to have two full moons, meaning a rare blue moon will shine this Halloween, on Oct. 31.

This full moon, named for the East Coast corn harvest, will reach peak fullness at 1:22 a.m. EDT (5:22 UTC) on Wednesday, Sept. 2, according to NASA

Laura Geggel
Managing Editor

Laura is the managing editor at Live Science. She also runs the archaeology section and the Life's Little Mysteries series. Her work has appeared in The New York Times, Scholastic, Popular Science and Spectrum, a site on autism research. She has won multiple awards from the Society of Professional Journalists and the Washington Newspaper Publishers Association for her reporting at a weekly newspaper near Seattle. Laura holds a bachelor's degree in English literature and psychology from Washington University in St. Louis and a master's degree in science writing from NYU.