Full November ‘beaver moon’ and lunar eclipse to put on a sky show this week

Sky watchers will get a double treat as November 2020 comes to a close, with a partial lunar eclipse occurring as the full “beaver moon” shines in the early morning sky.

The beaver moon — nicknamed such because this is the time of year when beavers build their winter dams in preparation for the cold winter — will reach its fullest phase Monday morning, Nov. 30, at 4:30 a.m. Eastern time. So it will look big and bright in the sky Sunday night and Tuesday night as well — assuming the clouds don’t block your view.

(Unfortunately, a big rain storm is expected to lash the New Jersey region on Monday, and it could linger into early Tuesday.)

Partial lunar eclipse

As the moon is becoming full early Monday morning, there will be a partial lunar eclipse — known as a penumbral eclipse. While it’s not as dramatic as a full lunar eclipse, experts say it could be visible to sky watchers here in New Jersey and in other areas of North America.

A penumbral eclipse takes place when the moon drifts through the outer section of Earth’s shadow, or penumbra, and part of the sun’s rays are blocked from shining on the moon during that time, according to astronomy experts at EarthSky.org.

On Monday morning, “the moon will take 4 hours and 21 minutes to glide across the pale outer fringe (penumbra) of Earth’s shadow, never reaching the shadow’s dark umbra,” says Space.com astronomy writer Joe Rao.

“About 20 minutes prior to the deepest phase of the eclipse, you might see some evidence of this faint penumbral shading on the moon’s upper edge,” Rao notes. “This corresponds to around 4:22 a.m. EST; 3:22 a.m. CST; 2:22 a.m. MT and 1:22 a.m. PST.”

If this was a full lunar eclipse instead of a partial one, the entire moon would be briefly darkened and give off a reddish-orange tint.

By the way, it is totally safe to look at a lunar eclipse with a telescope, binoculars or your own eyes. No special filters are needed.

Origin of the beaver moon nickname

The nickname “beaver moon” comes from Algonquin Native American tribes and American colonists, who gave nicknames to each full moon based on weather conditions, farming routines and hunting trends at that time of the year.

Some publications, like TimeAndDate.com, say the November moon got its name “after beavers who build their winter dams at this time of year.”

The Farmers’ Almanac says the nickname may have been derived from beavers preparing for winter in November, but notes it could have something to do with hunters. “This was the time to set beaver traps before the swamps froze, to ensure a supply of warm winter furs,” the publication says.

Other nicknames for the full November moon

Just like other full moons throughout the year, the November full moon has generated a few different nicknames over time.

In addition to the popular “beaver moon” moniker, the November full moon also has been coined the “hunter moon,” the “mourning moon,” the “reed moon” and the “frost moon” — a reference to the weather getting colder during this month.