Early on Election Day morning, early risers will have the opportunity to observe the November Beaver Moon undergoing a total eclipse.
This will be the fourth and final lunar eclipse that took place at an interesting half-year interval from May last year this year. Three of these eclipses in this series are complete. One of them – the lunar eclipse of last November 19 – was partial, but minimal; All but about two percent of the moon was immersed in Earth’s dark umbra (the darkest, innermost part of a shadow). Had last November’s eclipse been recorded as a total, it would have formed four totalities spanning 2021 and 2022: a cycle known as the lunar eclipse tetrad..
Heading our way next Tuesday morning, it favors the western half of North America and the Hawaiian Islands (where the moon will appear almost directly overhead in the middle of the eclipse). Along the Atlantic Coast, the moon will set as it begins to emerge from the total eclipse. Eclipse for Central and East Asia, Indonesia, New Zealand and Australia will occur on Tuesday evening as the moon rises.
Related: Lunar eclipse 2022: When, where and how can we see them?
In total, Space.com estimates that 2.7 billion people will have an opportunity this month – weather permitting – to enjoy the best part of the show. In other parts of the world, either only partial phases of the eclipse will be visible, or the eclipse will occur when it is daytime and the moon is not above their local horizon.
This map and accompanying diagram (opens in new tab) Images showing the Moon’s trail in Earth’s shadow are courtesy of Eclipsewise.com. The timeline below tells you what and when to expect in your location. The lines indicate that the moon is setting and is below the horizon.
| eclipse event | EST | CST | MST | PST |
|---|---|---|---|---|
| Does penumbra appear first? | 3:48 | 2:48 am | 1:48 | 12:48 |
| The moon enters the umbra | 4:08 | 3:08 am | 2:08 am | 1:08 am |
| The total eclipse begins | 5:16 | 4:16 | 3:16 | 2:16 am |
| middle eclipse | 5:59 | 4:59 | 3:59 | 2:59 am |
| total eclipse ends | 6:41 | 5:41 | 4:41 | 2:41 am |
| moon leaves umbra | —- | —- | 5:49 | 4:49 |
| Penumbra appears last? | —- | —- | 6:09 | 5:09 |
Stages of Eclipse
A total lunar eclipse has five phases, each with different things to watch.
The first penumbra phase begins when the moon’s leading edge enters the faint outer edge of Earth’s shadow, called the penumbra. But the shading is so weak that most people won’t notice anything until about 70% of the lunar disk is submerged in penumbra; or about 20 minutes before first contact with the much darker umbral shadow. Some people with exceptionally sharp vision can detect a penumbra when the moon is about halfway into the penumbra, or about 30 minutes before it first touches the shadow. Notice if there is a slight darkening of the upper left side of the moon. As the minutes pass and the moon goes deeper, the penumbra (or “spot”) becomes stronger.
The second stage is partial eclipse. This begins much more dramatically when the leading (left) edge of the moon enters the umbra, Earth’s inner shadow, where direct sunlight does not reach. With a telescope, you can watch the edges of the umbra as your local night sky gradually and gradually gets darker as it slowly absorbs craters, mountains, and the lunar sea (darker plains on the lunar surface). Note the Pleiades star cluster, which will be positioned above the Moon and becomes more prominent as the eclipse progresses.
Just over an hour into the partial eclipse, only one last bright sliver of the moon remains outside the umbra. And the rest of the month is probably showing an eerie reddish/copper glow. The contrast in both light and color has caused some to refer to it as the “Japanese lantern effect”.
Then comes the third phase: the total eclipse, which begins with the Moon’s last edge shifting into shadow. While the sun here is completely obscured, the moon is likely to shine a red or orange hue. These hues are caused by the shifting and bending of sunlight through Earth’s atmosphere: it is the combined light of all sunrise and sunset that surrounds our world at any given moment. If an astronaut stood on the Moon, he would see the sun completely hidden and the dark disk of Earth (which appears to us about four times larger than the moon) surrounded by a thin ring of red or orange light. And that light falls on the surrounding lunar landscape.
Is it light or dark?
On rare occasions, such as 1963 and 1992, the fully eclipsed moon turns almost black. In other cases, such as 1967 and 2003, it may look as bright as a freshly minted penny. Sometimes, it turns brown rather than a distinctive red or orange and is more like the color of a bar of milk chocolate.
During totality, two factors determine the brightness and color of the moon. First, how deeply the moon penetrates the umbra; the center of the umbra is much darker than its edges. For this upcoming eclipse, the moon will follow north of the center of the umbra. In the middle of the eclipse, the moon’s lower limbs will graze the center of the full shadow, but its upper limbs will be trapped within about 780 miles (1,250 kilometers) of the shadow’s outer edge. Therefore, the upper part of the lunar disk should appear noticeably brighter than the lower part.
The other factor is the state of the Earth’s atmosphere at the sunrise-sunset line. If the weather is very clear, the eclipse is bright. But if a large volcanic eruption recently polluted the atmosphere with an aerosol cloud or fine spherical haze, the eclipse would be ash gray or nearly black. Agung volcano in Indonesia in 1963 and Pinatubo volcano in the Philippines in 1991 were the main reasons for the very dark lunar eclipses that followed their eruptions.
Additionally, blue light refracted by Earth’s clear, ozone-rich upper atmosphere can add to the scene, especially near the edge of the umbra.
coming out of the shadows
As last May, the integrity period will be unusually long, lasting 85 minutes. And then, as the moon continues eastward along its orbit, events repeat in reverse order. The Moon’s leading edge comes back into the sunlight, ending the totality and beginning the fourth phase: partial eclipse again.
When the entire moon escapes the penumbra, only the final penumbra remains for the fifth phase. This last darkness gradually fades and the bright mid-autumn full moon returns to its normal appearance.
Look for Uranus too!
Coincidentally, the +5.6-magnitude planet Uranus will appear less than 2 degrees in the upper left corner of the moon during totality. With your binoculars or telescope, first observe the yellow-white +6.3 star HIP 13448, which will appear about one degree in the upper left corner of the moon during totality. Then continue a similar distance in the same direction until you come across another “star” that appears to be about twice as bright as HIP 13448. But it will not be a star, but the sixth planet from the sun. Can you see anything of the aquamarine blue-green hue of Uranus? Contrast with the orange-red moon can make this color a little more pronounced.
And for some fortuitous locations: northwestern North America, Asia, Japan, and the Arctic regions, the moon will actually obscure (hide) Uranus.
In a telescope, Uranus is a small disk 3.7 arcseconds wide. It is 1.74 billion miles (2.8 billion km) from Earth compared to the Moon’s distance of 240,000 miles (387,000 km).
Joe Rao serves as an instructor and visiting lecturer in New York. Hayden Planetarium (opens in new tab). writes about astronomy Journal of Natural History (opens in new tab), Farmer’s Almanac (opens in new tab) and other publications. Follow us on Twitter @Spacedotcom (opens in new tab) and on Facebook (opens in new tab).
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