The celestial bodies are aligning for a show this weekend, though clouds over Portland might block it from view.
A penumbral lunar eclipse will take place late Sunday night in Monday morning, Nov. 29 to 30, according to NASA, gradually darkening the face of the moon for more than four hours. It will be the second lunar eclipse visible in Oregon this year, following a previous penumbral eclipse in July.
A lunar eclipse occurs when the Earth’s shadow falls over the moon, and it can only happen at a full moon when then sun, Earth and moon all align. A penumbral eclipse is much more subtle than a total or even partial eclipse, as only the lighter outer shadow of the Earth (called the penumbra) darkens the moon.
During a penumbral lunar eclipse, the moon gradually grows a little darker until the maximum eclipse, after which it gradually lightens again. Unlike during a total or partial eclipse, the face of the moon won’t darken completely, and some people may not be able to notice a difference at all.
The eclipse is expected to begin Sunday at 11:32 p.m., reaching the maximum eclipse at 1:42 a.m. Saturday, and ending at 3:53 a.m., according to timeanddate.com.
Whether or not we’ll actually be able to see it in the Portland area will depend on the cloud cover. While skies should be clear Sunday during the day, clouds are expected to roll in overnight, the National Weather Service has forecast.
Two more lunar eclipses will be visible in the Pacific Northwest over the next year. A total lunar eclipse is set to take place May 26, 2021, in the wee hours of the morning, and a partial lunar eclipse from Nov. 18 into 19, 2021 will be visible across all of the Americas.
A solar eclipse always occurs about two weeks before or after a lunar eclipse, said Jim Todd, director of space science education at OMSI, but this time most of the world will miss out: The next total solar eclipse will be on Dec. 14, visible only from Chile and some parts of Argentina. Some regions of South America, southwest Africa and Antarctica will be able to see a partial solar eclipse.
The Pacific Northwest won’t see another solar eclipse until the annular solar eclipse of Oct. 14, 2023 and the total solar eclipse of April 8, 2024.