Catch the Full Worm Moon Coming in March

The full worm moon occurs at the start of spring.
The full worm moon occurs at the start of spring. / mkotera555/Moment/Getty Images (moon); Justin Dodd/Mental Floss (frame)

You’ll have to be an early bird to catch a glimpse of March’s full worm moon at its peak in 2023. It will achieve its full potential on the morning of Tuesday, March 7. Here’s what else you need to know.

The Origins of the Worm Moon

As The Old Farmer’s Almanac explains, March’s full moon has been known as the “worm moon” because the ground is usually soft enough for earthworm casts (a.k.a. worm poop) to start fertilizing soil, and other signs of spring soon follow. An 18th-century account traced back to the Dakota suggests that the “worm” actually refers to beetle larvae that emerge from tree bark in early March. It’s also sometimes called the “full sap moon,” since March is also the time of year when sugar maples start leaking sap.

When to See the Full Worm Moon

The best times to catch the worm moon are the night of Monday, March 6 through the morning of Tuesday, March 7, 2023. At 7:42 a.m. Eastern time, the moon will be at its fullest. It will also appear slightly less voluminous on the nights surrounding the full moon date.

This year’s worm moon promises to be bright, but it has a big reputation to live up to. In 2021, a full worm supermoon helped free the giant container ship Ever Given from where it was stuck in mud in the Suez Canal. The supermoon caused tides to crest about 1.5 feet higher than normal, giving the ship enough leverage to float clear of the shores.

A version of this article ran in 2020; it has been updated for 2023.