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The Sky This Week
U.S. Naval Observatory's Weekly Blog
Falling Stars and a Vanishing Moon
by Geoff Chester, USNO Public Affairs
16 November 2021
Total Lunar Eclipse, 2014 October 8, 10:38 UT
imaged with an 80-mm (3-inch) f/6 Antares Sentinel refractor
and a Canon EOS Rebel T2i DSLR from Alexandria, Virginia.
The Moon waxes to her full phase this week as she climbs northward into the rising stars of the winter sky. November’s Full Moon is popularly called the Beaver Moon, at least here in North America. It is also known as the Frost Moon or Oak Moon in other cultures. Whatever you call it, Full Moon occurs on the 19th at 3:57 am Eastern Standard Time. At that time Luna will be just over five degrees southwest of the Pleiades star cluster. She ends the week among the stars of Gemini.
If you happen to be up early on the morning of the 19th to view the Moon, you will be treated to one of Nature’s celestial spectacles in the form of a nearly total lunar eclipse. Luna first touches the Earth’s umbral shadow at 2:18 am EST, but you may begin to notice a subtle darkening of her upper left limb some 20 minutes earlier. Mid-eclipse occurs at 4:02 am, at which time just over 97 percent of the Moon’s disc is within the umbral shadow. Luna exits the umbral shadow at 5:47 am when she will be low on the western horizon as morning twilight gathers in the east. Sunrise occurs in Washington just over an hour later. Locations in the western U.S. will have a view of the entire eclipse, with observers in Hawai’i being treated to a “prime time” eclipse experience. This should be a very interesting eclipse to watch. Since the Moon will be close to her most distant apogee of the year she will be moving at her slowest along her orbit, providing us with the longest-duration partial eclipse for the next 1000 years! It will also be interesting to see how dark the umbral shadow will be, and how that affects the visibility of the nearby Pleiades. If you don’t feel like getting up in the wee hours or if the weather is poor you won’t have to wait too long for the next lunar eclipse opportunity. We will be treated to a total lunar eclipse on May 16 next year.
Bright moonlight will wash out this year’s Leonid meteor shower, which peaks on the morning of the 17th. This shower is produced by debris sputtered off the surface of Periodic Comet Tempel-Tuttle, co-discovered by astronomer Horace P. Tuttle at the U.S. Naval Observatory on January 6, 1866. With a period of 33 years, the comet has produced a number of intense displays near the times when it passes through the inner solar system. The great Leonid “storms” of 1833 and 1966 each produced a nearly constant “rain” of meteors for several hours, and intense displays also occurred in 2000 and 2001. However, in “off” years a single observer under dark skies might be lucky to see a dozen or so over an hour.
One of the witnesses of the 1833 display was a young Abraham Lincoln, who was rousted out of bed in Salem, Illinois by the local church deacon, who feared that the Judgement Day had surely come. Lincoln beheld the spectacle, but he noted that the familiar stars of the constellations remained fixed in the sky. Many years later, during the darkest days of the Civil War, he was asked about his faith in the Union’s survival. Relating his experience on that night in 1833, he was heard to say “Gentlemen, the world did not come to an end then, nor will the Union now.”
Venus leads the trio of bright planets that now grace the early evening sky. The dazzling planet pops into view just after sunset in the southwestern sky, and as twilight deepens she dominates that part of the sky. She is gradually beginning to climb northward from her southernmost point of the current apparition, and for the next few weeks she will be at her best viewing for the year.
Pale yellow Saturn sits between his brighter companions Jupiter and Venus and should be easy to spot about 20 minutes after sunset. You will need to train the telescope on him early in the evening to get a crisp view of his signature rings before he sinks into denser air above the southwest horizon. He now sets just before 10:00 pm local time.
Jupiter, like Venus, should appear shortly after sunset. The giant planet is a bit higher than Saturn, which helps with telescopic views. On the evening of the 21st you should have a good view of his famous Great Red Spot as the shadow if his innermost large moon Io dances across his cloud tops. You should be able to spot these phenomena with a good four-inch telescope at around 6:00 pm local time.
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