Chicagoans will have the opportunity to see a total lunar eclipse Thursday, the first total lunar eclipse visible from Chicago since November 2022.
A total lunar eclipse happens when the Earth, sun, and moon align in a way that the moon passes directly through Earth’s shadow.
“This only happens during a full moon, when the moon is on the opposite side of the Earth from the sun,” said Michelle Nichols, director of public observing at the Adler Planetarium. “However, because the moon’s orbit is slightly tilted relative to Earth’s, not every full moon results in an eclipse.”
Partial lunar eclipses can happen a few times a year, but total eclipses are less common, according to the National Weather Service. For a total lunar eclipse to occur, the entire moon must pass into the Earth’s shadow. The next total lunar eclipse visible from Chicago is expected to be in March 2026.
The eclipse is expected to begin at 10:57 p.m. Thursday, but changes in the moon’s brightness won’t be immediately noticeable. A partial eclipse will become visible at 12:09 a.m. Friday, and the total eclipse will be reached at 1:26 a.m.
The moon may appear reddish when it is completely within Earth’s shadow.
Totality will last until 2:31 a.m., after which the moon slowly moves out of Earth’s shadow. The eclipse ends at 5 a.m.
“As the moon moves into the Earth’s shadow, the shading effect becomes noticeable,” Nichols said. “Initially, it may look like a small, dark ‘bite’ is being taken out of the moon.
“As the eclipse progresses, the moon enters the darkest part of Earth’s shadow, known as the umbra. At that point, the moon can appear reddish, orange, or even dark gray.”
The color change is caused by the way Earth’s atmosphere filters sunlight.
For anyone planning to watch the eclipse, finding the right viewing spot makes a difference. For the best view, scientists recommend finding a place with minimal light pollution, such as a park or the lakefront.
Binoculars or a telescope can enhance the experience but are not necessary to see the eclipse.
“To view the eclipse, you don’t need any special equipment — just your eyes and a clear sky,” Nichols said. “As long as the weather cooperates and the moon is above the horizon, you’ll be able to see it.”