Night owls and insomniacs will be the only people to see a remarkable sky show next week.
Why? Because for much of North America, the full moon will be experiencing one of nature’s great sky shows during the wee hours of Tuesday, Nov. 8: a total lunar eclipse.
Most skywatchers will see the start of this eclipse (weather permitting), but depending on where you live, you may see only a portion of the event. In general, the farther west you live, the more of the eclipse you will see before the moon sets.
A lunar eclipse occurs when the full moon slips into the shadow of the Earth far out in space. This occurs every six months or so when the sun, moon and Earth are aligned.
Sometimes the moon only partly enters this shadow, and we see what’s called a partial eclipse. Other times it passes closer to the shadow’s center and we see the moon fully engulfed: a total lunar eclipse.
And that’s just what will happen on the morning of Nov. 8.
At 12:02 a.m. PST, the moon will enter the Earth’s light outer shadow called the penumbra, but this is so thin that no one will notice a darkening of the moon’s appearance.
Within an hour or so, that will change. As the moon approaches the dark inner shadow of the Earth, known as the umbra, skywatchers will notice the eastern side of the moon beginning to darken slightly.
The real show begins at 1:08 a.m. PST when the moon officially enters 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 will dim as it enters more deeply into our planet’s umbra until 2:59 a.m. PST when it reaches its maximum eclipse. Eclipse watchers on the East Coast will have a treat as they watch the partially eclipsed moon descending over the western horizon.
During mideclipse, the moon will take on a strange coppery hue because sunlight passing through our atmosphere is reddened and bent inward toward the darkened surface of the eclipsed moon.
At 3:42 a.m. PST, the moon will begin to recede from the shadow. The partial phase will last until 4:49 a.m. PST.
Unlike an eclipse of the sun, a lunar eclipse is perfectly safe to view without protective filters. Your eyes are all you need, but you’ll have even more fun with binoculars or a small telescope.
If the sky is cloudy that morning, or if you live in an area where it won’t be visible, you can watch a livestream of the eclipse. Click here to find details for your location as well as links to view it live online.
If you miss this sky show, North Americans will have to wait a year for the next partial lunar eclipse visible here, and 2½ years for the next total lunar eclipse.
— Dennis Mammana is an astronomy writer, author, lecturer and photographer working from under the clear dark skies of the Anza-Borrego Desert in the San Diego County backcountry. Contact him at dennis@mammana.com and connect with him on Facebook: @dennismammana. Click here to read previous columns. The opinions expressed are his own.