Total Lunar Eclipse on May 26: Strange and Short

Plus the closest, brightest supermoon of 2021

May 25, 2021
Total Lunar Eclipse

A total lunar eclipse of the full Flower Moon happens early Wednesday morning, May 26. It all sounds great—until you read the fine print. Turns out, it will only be “total” for those on or near the West Coast. And even then, the Moon will be so low in the sky—less than 15 degrees when totality begins—that hills, trees, or houses can easily obscure it. Learn about this strange and short total lunar eclipse—and what you will see without the hype!

This One’s for the West Coast

In North America, it’s only a total lunar eclipse for those on or near the West Coast. The winners will be those with unobstructed Pacific Ocean views who are willing to set the alarm for about 3:30 AM. Yes, this total lunar eclipse happens before dawn! It’s also very low on the horizon so make sure your view to the Southwest horizon is clear and not blocked by houses, trees, or hills.

Pacific Daylight Time (Wednesday, May 26)
Penumbral eclipse begins: 1:46 a.m. PDT (The Earth’s penumbra starts touching the Moon’s face.)
Partial eclipse begins: 2:45 a.m. PDT (Moon is getting red.)
Total eclipse begins: 4:11 a.m. PDT (Completely red Moon. Very close to horizon!)
Total eclipse ends: 4:26 a.m. PDT 
Partial eclipse ends: 5:52 a.m. PDT (not directly visible)

See more 2021 eclipse dates and times.

Further east, observers won’t get a fair chance. In Denver, for example, a partial lunar eclipse unfolds in the hours before dawn, but the Moon sets before totality begins. Even further east the situation is hopeless. This time, the entire eastern U.S. and Canada see nothing whatsoever, since the Moon sets before the action begins.

I recommend that those in the eastern U.S. and Canada forget about this immediately, since nothing’s happening. And those on the West coast who aren’t eclipse fanatics or astronomers should probably sleep this one out too, and instead circle November 19 on their calendar (see more on that below).

Why Is the Total Lunar Eclipse So Short?

The total eclipse, or the time when the Moon is in deepest shadow, will last less than 15 minutes. That can be nice and compact or subpar, depending on your view. The main question is: Why so short?

As a reminder, a total eclipse of the Moon happens when Earth comes between the Sun and the Full Moon so that all three are in alignment. The Earth blocks the Moon so that the Sun’s light can not light up the Moon’s disk. What you see is the Earth’s shadow covering the Moon. On May 26, the Earth, Moon, and Sun are not in perfectly alignment so the full Moon doesn’t travel through the very center of Earth’s shadow. A more perfect alignment would result in a deeper, longer total eclipse.

For those who see totality, the Moon will appear a reddish-orange color. This is because some sunrays still make it through Earth’s atmosphere to the Moon. This reddish hue is why some folks call a total lunar eclipse a ”Blood Moon.”

Prior to totality, a “partial lunar eclipse” happens. A small part of the Moon’s surface is covered by the darkest, central part of the Earth’s shadow, called the umbra. In a partial eclipse, Earth’s shadow appears to take a bite out of the moon.

Image: Partial Lunar Eclipse. Credit: NASA

Different Types of Eclipses

Remember, the word “eclipse” can mean anything from a life-altering experience to a dud. The grandest variety, so powerful it often makes people weep, is a total solar eclipse, when pink flames or prominences leap from the Sun’s edge. But those average just once every 360 years for any given location, and usually requires a pilgrimage.

Nothing comes close to such a solar totality in terms of spectacle. But most other eclipse varieties are still fascinating to observe. These are the partial solar eclipses (which require special filters for eye safety) as well as the total and partial lunar eclipses dicussed above.


But there’s yet another category, a somewhat secret grouping rarely mentioned by our hype-dominated press: the ones not worth setting an alarm for. These include the penumbral lunar eclipses, when the Full Moon basically doesn’t change so there’s nothing to see. And that’s the kind with which we’ve lately been plagued. The last four lunar eclipses have all been penumbral! It was a truly noteworthy string of subpar eclipses even if some in the media remarkably proclaimed two of those as “super,” too. Another variety of nuisance eclipse is when an actual partial or total event happens but our spinning planet has swiveled your home to face the wrong direction. Nearly half of all eclipses are invisible for that reason.

Mark Your Calendars

North America will get a better deal on November 19, 2021 when the whole country and Canada will experience a 99% total eclipse of the Moon high up without obstruction! It’ll be perfectly visible from the entire continent, even Hawaii and Alaska. 

So unless you’re on or near the West Coast and have a clear low-down view of the western horizon this week, you can sleep through this event without guilt, while making sure to put November 19 in your scheduling app or calendar!

The Biggest Supermoon of 2021

Here’s the good news: Sky watchers all over the world will see a “supermoon” in the night sky! on the 26th. The Full Moon of May crests within hours of “perigee” which is the Moon’s closest point to Earth in its orbit. In fact, this is the closest perigee of 2021 so the Moon will appear especially big and bright all night long, rising at sunset in the east and setting at sunset in the west.

See the Almanac’s Guide to May’s Super Full Flower Moon!

About This Blog

Welcome to “This Week’s Amazing Sky,” the Almanac’s hub for everything stargazing and astronomy. Bob Berman, longtime and famous astronomer for The Old Farmer’s Almanac, will help bring alive the wonders of our universe. From the beautiful stars and planets to magical auroras and eclipses, he covers everything under the Sun (and Moon)! Bob, the world’s mostly widely read astronomer, also has a new weekly podcast, Astounding Universe