Just when folks were adjusting to the recent time change, along comes another cause for sleep interruption: a middle-of-the-night lunar eclipse.
If the skies are clear, Chicagoans will have an excellent chance of seeing the eclipse Friday morning, with the best hours for viewing the event being approximately 1:30-4:30 a.m.
Technically the eclipse is only considered partial, but with 97% of the moon in shadow, that’s “close enough” to total, said Michelle Nichols, director of public observing at the Adler Planetarium.
Here’s what you need to know to prep for the celestial show.
What is a lunar eclipse?
During a lunar eclipse, Earth is positioned between the moon and sun, with the moon shrouded in the shadow that Earth casts into space, Nichols explained. (In a solar eclipse, the moon comes between Earth and the sun.)
In a total eclipse, the entire moon is shaded by the darkest core of Earth’s shadow (called the umbra). A partial lunar eclipse occurs when the umbra covers only part of the moon.
The lighter part of Earth’s shadow is the penumbra. While the moon is passing through the penumbra, which occurs at the beginning and end of an eclipse, the change will be difficult to discern.
What does a lunar eclipse look like?
It won’t appear as if a bite’s been taken out of the moon, but instead the moon will be shaded.
“People often ask what color the moon is going to be. It’s difficult to say,” said Nichols. “It could be dark gray to light orange and everything in between. It could be brick red.” At the moment, she’s leaning toward gray.
The color comes from indirect sunlight reaching the moon, passing through Earth’s atmosphere. “The color could change due to cloudiness or things like how much dust is in the atmosphere,” she said.
What’s the timing?
— The moon will begin to pass into the penumbra (lighter shadow) at 12:02 a.m. Friday.
— It will begin to enter the umbra (darker shadow) at 1:18 a.m., which is when things start to become visible to the naked eye.
— At 3:02 a.m., almost the entire moon will be shaded by the umbra.
— The moon starts to exit the umbra at 4:47 a.m.
— By 6:03 a.m., the moon will be passing out of the lighter shadow.
How can I watch?
There’s no special equipment needed, other than maybe an alarm clock. Just try to find an open space away from trees, tall buildings and excessive light pollution, Nichols said.
That’s harder for folks in the city than the suburbs, though the amount of leaves still on trees is making visibility slightly trickier than normal everywhere, she added.
Look for the moon about two-thirds up in the sky, in the southwest. It will gradually sink throughout the course of the eclipse, said Nichols.
For those who’d like to watch from the comfort of their bed or couch, Nichols will be hosting a livestream on the Adler’s Sky Observers Hangout YouTube channel beginning at 1:30 a.m. Friday.
If the sky is clear, she’ll show live images of the eclipse. If it’s cloudy, she’ll talk, answer questions and maybe tap into a livestream from a luckier part of the country, Nichols said.
For a veteran like Nichols, who’s been stymied by weather on plenty of occasions, the unpredictability of sky watching comes with the territory. There have been times, she said, when she’s missed the totality of an eclipse because snow started falling at precisely the wrong moment.
“You just take what you get. You’re not guaranteed a view,” she said.
What else is unusual about this month’s full moon?
By now, we’ve all heard of “supermoons,” which occur when the moon is both full and at its closest orbital point to Earth. That relative proximity causes the moon to appear larger than normal.
This month’s full moon is the opposite: a micromoon.
Micromoons occur when a full moon coincides with the satellite’s farthest orbital point from Earth. It can appear slightly smaller and dimmer.
The next total lunar eclipse, which should be visible in Chicago, will take place May 16, 2022.