June 5, 2023

Night owls in California and other western areas will be pampered on May 26, when the moon enters Earth’s shadow and turns a blood red color during a total lunar eclipse, the first in over two years visible from the United States.

And if you hear anyone call this a super blood moon, it’s because the moon is also positioning itself on its closest approach to our planet, an event that some call a supermoon.

“You will actually see how the solar system works and Newton’s laws of gravity are in effect before your very eyes,” said Edwin Krupp, director of the Griffith Observatory in Los Angeles.

This month’s event will be visible primarily from Australia, East Asia, Pacific Islands and West America. People on the west coast of the United States, from southern California to Washington state, can expect the action to begin around 1:47 a.m. Pacific time on May 26.

In the beginning, the moon will only enter the earth’s outer shadow, known as the penumbra. Changes to the lunar surface will be subtle at first, said Dr. Croup.

After sailing for the next few hours, the moon moves deeper into the shadows. At this point it looks like something took a bite out of it. During this phase it becomes reddish. This begins around 2:45 p.m. Pacific time.

At 4:11 a.m., the moon falls completely into the inner rain shadow of the earth and its full face turns deep red. The quirks of the lunar orbit mean this total solar eclipse will be relatively short, lasting about 14 minutes, and ending at 4:25 a.m. Pacific time. Some total lunar eclipses last almost an hour.

But the solar eclipse is not over yet and sky watchers can enjoy seeing the process reverse as the moon emerges from the earth’s umber and penumbra and gradually returns to its normal self by sunrise. At that point it will sink below the horizon for West Coasters.

On Tuesday afternoon, weather forecasters expected the skies to be relatively clear in many parts of northern California during the time of the solar eclipse along the coast. But fog could cover some coastal areas around Los Angeles and San Diego, which could obscure the view of the moon.

Astrophotographers on the eclipse path may want to try setting up a telephoto lens on a tripod and varying the exposure at a few different shutter speeds to get the best shot, suggested Dr. Krupp forward.

A cell phone camera usually makes the moon appear pretty small, he added, but keen observers can usually play around with their phone’s settings to get a nice picture.

I’m sorry to say no.

As a consolation for others in the country, the Griffith Observatory is hosting a live feed of the solar eclipse on its website from 1:45 a.m. to 5:50 a.m. Pacific time. You can also watch it in the video player embedded above. This means that people in the eastern time zone who wake up early enough can watch part of the show online.

Lunar eclipses occur when our planet stands between its two great heavenly companions, the sun and the moon. Moonglow is actually reflected from sunlight and so the lunar surface gradually darkens as the moon falls into the long shadow of the earth.

Sometimes the celestial movements of the moon cause it to brush only part of the shadow of our planet, resulting in partial lunar eclipses that are often difficult to see. But the event later this month will see our natural satellite completely obscured by the mass of Earth.

During such events, a small amount of sunlight is directed around the edges of our planet. The earth’s atmosphere filters out everything but the longer, redder wavelengths that are projected onto the moon. The copper-colored light – a combination of all the sunrises and sunsets in the world – creates the scarlet color of the moon during a total solar eclipse.

“It’s quite a spectacle,” said Madhulika Guhathakurta, an astrophysicist at NASA’s Goddard Spaceflight Center in Greenbelt, Md.

The moon’s orbit is not a perfect circle around the earth, but an ellipse. Sometimes it is closer and further away from our planet. This month’s supermoon should make our natural satellites appear about seven percent larger and brighter than usual in the sky, although most people will have a hard time telling the difference.

When the moon is close to the horizon, it usually appears extremely large, a well-known optical illusion that has not yet been fully explained. Some people hear about supermoons, see this effect and think they have seen something special. But the two have nothing to do with each other, said Dr. Croup.

Supermoons with lunar eclipses are not uncommon. The last Super Blood Moon was January 21, 2019 and the next is May 16, 2022. The fact that the headlines have focused on creating fun names like the “Super Flower Blood Moon” for this month’s solar eclipse is strictly a product of the Internet age, “said Dr. Croup. “We are paying much more attention to heavenly events than before.”

But in that sense it is almost a return to an earlier era when heaven was much more important to people’s lives in everyday life.

“I don’t have an argument with the digital age, which is drawing attention to things that would go by without notice,” he added.

Research during lunar eclipses has a long pedigree. Aristotle demonstrated that the earth is a sphere by pointing out that it always casts a round shadow on the moon, no matter where on the ground the solar eclipse was seen or where the moon was in the sky. Only a spherical object can create a circular shadow from any angle.

Today, NASA has used instruments on the Lunar Reconnaissance Orbiter, a robotic spaceship around the moon, to take temperature measurements of the lunar surface as it passes into the shadow of the earth. By observing how quickly different rocks cool, scientists can infer their density, said Dr. Guhathakurta.

She was pleased that people around the world are paying more attention to astronomical phenomena such as eclipses.

“They are beautiful to look at and they also teach us science,” she said.