The full moon of January, called the Wolf Moon, will occur in the U.S. just after midnight on the night (January 20-21), and viewers in the Americas, northwestern Europe and even the Arctic will be treated to a lunar eclipse.
The moon becomes official for observers on the East Coast of the United States on Jan. 21 Wed at 12:16 am Eastern Standard Time, according to NASA's SkyCal. Moonrise is at 4:32 p.m. the evening of Jan. 20 and moonset is the next morning at 7:36 am, according to the U.S. Naval Observatory. The moon will be in the constellation of Aquarius, and rises about 27 minutes before sunset (which happens at 4:59 pm, per USNO).
The full moon is because the moon is exactly on the opposite side of the Earth from the sun. Most of the time the moon looks illuminated because we see the sun's light reflected off it. But once in a while the moon's orbit carries it into the shadow of the Earth. This does not happen every month because the moon's orbit is tilted five degrees with respect to the plane of Earth's orbit, so Earth's shadow usually misses the moon. This month, however, the moon will fall into the shadow and be eclipsed. [Super Blood Moon Total Lunar Eclipse: Complete Guide]
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According to timeanddate.com, the lunar eclipse actually begins on the evening of Jan. 20 th 9:36 p.m. Eastern Time. That's when the moon enters Earth's penumbra, the light shadow that surrounds the umbra, the darker shadow that actually obscures the moon. The penumbral shadow is hard to see – most observers do not notice it, except perhaps as a slight change in the quality of the light of the moon. At 10:33 p.m. Eastern moon touches the umbra, the shadow that makes the moon look dark. At first, the moon will look as though a "bite" has been taken out of it, and the edge of the shadow can look a bit fuzzy. But as the evening progresses, the moon will be obscured.
By 11:41 p.m. (per timeanddate.com) the moon will be in the shadows' shadows and begin to look red. The red color is because the light from the sun passes through Earth's atmosphere, and is scattered. Longer wavelengths are red, and those are the ones that tend to get through the atmosphere; shorter wavelengths (the yellow, green, blue and violet) tend to be scattered more. (If a person was standing on the moon, she would see a solar eclipse, and the Earth surrounded by a reddish-orange halo). This is when the total eclipse starts, and it will last for about 61 minutes; maximum eclipse, when the moon is deepest in the shadow of Earth, will be at 12:12 am, just a few minutes before the official full moon.
At 12:43 am the morning of Jan. 21 the moon will reach the edge of the earth's umbra, and begin to emerge into the penumbra. The red color will start to fade, and the shadow will start to look black once again. By 1:50 am Earth's umbra will reach the edge of the moon and our satellite will be in the penumbral shadow. The eclipse ends at 2:48 am
For observers in Europe, the entire eclipse will be visible if one is in the British Isles, Portugal, Norway, . The eclipse will start later in the night, in the wee hours of Jan. 21. In Lisbon, for example, the moon touches the umbra at 3:33 am. and will start to look red at 4:41 am, maximum eclipse is at 5:12 am. and the moon will emerge from the umbra at 6:50 am Sunrise, meanwhile, is at 7:51 am. per the USNO . As one moves east, the moon will set before the penumbral part of the eclipse ends. For example, in Paris, the moon sets at 8:46 am. local time on Jan. 21, and the penumbral eclipse will end at 8:48; but the observers will be able to see the more visible and spectacular shadow in its entirety – the moon enters Earth's darker shadow at 4:33 am.
For those in the west, the eclipse starts relatively early in the evening and ends just after midnight. In Los Angeles, for example, the moon begins to look dark on Jan. 20 at 7:33 p.m. local time and emerges from the umbra at 10:50 p.m. The only part of the U.S. that will not see the whole umbral phase is Hawaii – the moon turns red at about 5:33 p.m. local time and will still be below the horizon. On the other hand, Hawaii observers will see the moon rise at 6:07 pm, already deep in Earth's shadow. The maximum eclipse will be at 7:12 pm, and the moon will be a deep red. The eclipse's shaded phase ends at 8:50 pm
Lunar eclipses are called blood moons, because of their reddish color. Many cultures have had myths of some creature temporarily swallowing the moon; Incan peoples saw the moon as being devoured by a jaguar, while the Norse saw eclipses as manifesting wolves chasing the sun and moon across the sky, and temporarily devouring them.
Aside from eclipses, the January full moon is often called the Wolf Moon, according to the Old Farmer's Almanac, and may date back to Native American tribes and early Colonial times when wolves wouldlll outside villages.
According to the Ontario Native Literacy Project, the Ojibwe (or Aanishnabeg) people called it Mnido Giizis, the Spirit Moon, marking a time of prayer and contemplation. The Cree called it the Opawahcikanasis, or frost exploding moon, as the trees would make a crackling sound due to the extreme cold.
The Tingit of the Pacific Northwest calls the January full moon T'awaak Dís, or Goose Moon, while Haida called it Táan Kungáay, or "Bear hunting moon," according to the Tlingit Moon and Tide Teaching Resource published by the University of Alaska at Fairbanks.
In the southern hemisphere, December is during the summer, and the Māori of New Zealand described the lunar months in November to December as Hakihea or "birds are now sitting in their nests," according to the Encyclopedia of New Zealand.
In China, the traditional lunar calendar calls the December lunation the 11th month. Called Dōngyuè, Winter month, it marks the winter solstice. (The month actually begins on Dec. 6, because lunar and solar calendars fall out of sync).
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