Whole lunar eclipse might be difficult to look at within the sky — however it’s positive to shine on-line

If you’re on the West Coast, watching tonight’s total lunar eclipse will require a willingness to stay awake in the middle of the night — plus a lucky break on the weather.

But maybe it’s worth taking a chance: The next opportunity to take in the sight of a blood-red, eclipsed moon won’t come until 2025. And even if it’s cloudy, you can hedge your bets by tuning in NASA’s live stream of the event.

Lunar eclipses occur when Earth and the moon are positioned such that our planet blocks out the sunlight falling on the lunar surface. During a partial eclipse, only a portion of the moon goes dark. Totality occurs when the moon passes directly through the darkest part of Earth’s shadow, known as the umbra.

The partial phase of tonight’s eclipse begins at 1:44 a.m. Tuesday, with totality lasting from 2:17 to 3:42 a.m. During the total phase, the only light falling on the moon’s near side will come from the reddish light refracted by Earth’s atmosphere. Put more poetically, it’s the light from countless sunrises and sunsets.

Unlike total solar eclipses, which can be seen only along a narrow track of territory, lunar eclipses can be seen by half a world at once. Tonight’s zone of totality is centered around the Pacific Rim and takes in Japan and Australia as well as Alaska and Ecuador.

Viewing prospects are, shall we say, less than ideal for Western Washington: The National Weather Service’s sky cover forecast for Seattle suggests that skies will be 80% clouded over during prime time. You’d have to drive east of Moses Lake to better your odds significantly.

Fortunately, NASA is planning online coverage of the eclipse starting at 1 a.m. PT — featuring video from vantage points around the zone of totality, plus an interview with NASA lunar scientist Noah Petro. Who knows? All this talk about totality just might get you fired up about the total solar eclipse that’ll be visible over parts of the U.S. on April 8, 2024 — and the next total lunar eclipse on March 13-14, 2025.