A full moon and lunar eclipse will wriggle through the sky this month
The moon is gearing up for some major performances in the next two weeks. As spring showers continue to fall from the skies and drench the soil, earthworms could be taken to new heights — and that’s not because of the birds feasting on them. March’s full moon, also known as the worm moon, will wriggle its way into the sky on March 25.
Not only will there be a full moon, but there will also be a penumbral lunar eclipse, which is set to be an understated opening act to the climactic total solar eclipse in a few weeks. Sky watchers nationwide could see the penumbral lunar eclipse subtly shade the moon early on March 25 — but note that it’s tricky to see.
Different cultures give names to the moon, often based on common seasonal activities. It is thought that the worm moon got its name from the critters that squirm on the ground when it rains in the spring. While this is true, Indigenous tribes may have been referring to the beetle larvae that come from defrosting trees, according to Almanac.com.
The worm moon has also been called the sugar moon by Ojibwe tribes, as it marks the time of year when sticky sap from sugar maples emerges. It’s also been called the crow moon by other Indigenous tribes, as it marks the bird’s reappearance.
But that’s not the only exciting thing about the full moon. As the moon rises above the horizon, it may appear larger than usual because of “moon illusion.” The moon isn’t actually bigger in size, but it appears a little bigger because your eye has something to compare it to like buildings or trees.
This is also the closest moon to the spring equinox. The spring equinox, which results in nearly an equal amount of daylight and darkness at all latitudes, signals the astronomical turning of seasons — meaning even warmer temperatures are on the way after a historically mild winter.
This year, the worm moon will rise about a week after the spring equinox. The moon will be at its fullest at 2 a.m. Eastern time on Monday.
The penumbral lunar eclipse
The full moon will also feature a very subtle eclipse. A penumbral lunar eclipse occurs when the moon travels through the Earth’s outer shadow, the penumbra, causing the moon to appear just a hair darker.
There are two parts to a shadow: the umbra, the inner and darkest part of the shadow, and the penumbra, the outer shadow. The next time you look at your shadow on the ground, try to spot the difference. You’ll be able to spot your more obvious dark shadow, but the fainter, lighter shadow around it may be tricky, said Elizabeth Warner, the director of the astronomy observatory at the University of Maryland.
“Just as the penumbra around your shadow is hard to see, it’s the same with the Earth’s outer shadow,” Warner said.
The penumbral lunar eclipse is like that song you always skip on your playlist. It’s not like the lofty total lunar eclipse — commonly known as a “blood moon” — which drapes the moon in a coppery-red coat. Or the partial lunar eclipse that obscures parts of the moon, almost as if a bite were taken out of it without fully covering it. There is generally a lunar eclipse every six months, according to Jean-Luc Margot, a professor of planetary astronomy at UCLA.
“These types of eclipses are very difficult to detect,” Margot said. “I would encourage the public to watch the other lunar eclipses or the solar eclipse.”
But this subtle eclipse may get people excited about the showstopping total solar eclipse on April 8. Thousands of people will travel to the roughly 115-mile-wide path that stretches from Mexico through Maine to watch the moon temporarily block the sun.
