Shadow on the Moon!
Last updated 12/7/2021 at 11:34am
Night owls and insomniacs will be the only ones to witness a rare cosmic alignment this week.
On the night of Nov. 18 and the morning of Nov. 19, the full moon drifted slowly into the shadow of the Earth, creating a beautiful partial eclipse of the moon.
At 10:02 p.m. PST (1:02 a.m. EST) that night, the moon entered the Earth's light outer shadow called the penumbra, but this is so thin that no one noticed a darkening of the moon's appearance.
Within an hour or so, that changed. As the moon approached the dark inner shadow of the Earth, known as the umbra, sky watchers noticed the eastern side of the moon beginning to darken slightly.
The real show began at 11:18 p.m. PST (2:18 a.m. EST) when the moon officially entered the umbra. No one gazing skyward will have any doubt that a "bite" has been taken out of the moon – a bite that will grow larger with each passing minute.
For more than an hour, the moon was dim as it entered more deeply into our planet's umbra until 1:02 a.m. PST (4:02 p.m. EST) when it reached its maximum eclipse. Because the moon was 97% covered, this is officially a partial eclipse, but to most, it will look quite total.
During mid-eclipse, the moon will take on strange, coppery hue. This color occurs because sunlight passing through our atmosphere is reddened and bent inward toward the darkened surface of the eclipsed moon. Just how red and dim it appears depends on and how dark your sky is and how transparent our planet's atmosphere is at the time. It could appear anywhere from bright orange to nearly invisible.
You can watch the sky show from even under bright city lights but, for a truly dramatic view, head out to dark rural skies. When you arrive there, of course, the sky will be washed out with brilliant moonlight, and you will see very few stars.
But just wait! During mid-eclipse, the brilliant stars of winter bursted into view, and you'll see the ruddy orb of the moon suspended just below the shimmering star cluster known as the Pleiades, or Seven Sisters.
After the eclipse reached its maximum, the moon will begin to recede from the shadow. The partial phase will last until 2:47 a.m. PST (5:47 a.m. EST), and some eclipse watchers on the East Coast will have a treat as they watch the partially eclipsed moon setting in the west.
Unlike an eclipse of the sun, a lunar eclipse is perfectly safe to view without protective filters. Your eyes are all you need, but with binoculars or a small telescope, you'll have even more fun.
If the sky is cloudy that night you can watch a live stream of the eclipse. Visit timeanddate.com to find details about the eclipse from your location, as well as links to view it live online.
If you missed this sky show, North America residents will have to wait two years for the next one – also a partial eclipse – and four years for the next total lunar eclipse.
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