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Looking Up

Sky events in the southwest after sunset are changing rapidly now. We start the month with three planets in a line, making an angle to the horizon (see the image). Starting with the low-est we have Jupiter, then Venus to the upper left of Jupiter and finally Saturn to the upper left of Venus. Venus will undoubted-ly be the first to see being the brightest. Start looking while the twilight is still bright. A crescent Moon will be higher in the sky and to the upper left of the trio. As the month proceeds, we lose Jupiter by the third week and conjunction with the Sun oc-curs on the 27th. Venus gets higher in the sky, passing Saturn on the 10th by less than two degrees. By the end of December, Venus is setting at 7:30pm, over two hours after sunset. Though Venus only brightens a little bit this month, it will seem brighter as it begins appearing in a darker sky. Just for trivia’s sake, Venus passes Pluto on the 12th by 1.3 degrees, but you’ll need a good-sized tele-scope to check it out!
For the point of view of the unaided eye, not much will be happening planet-wise the rest of the evening. The planet Uranus is near the bor-der of Pisces, Aries and Cetus, shining at magni-tude 5.7. If you wait until the third week of the month, when the bright Moon is out of the evening sky, you might give it a shot with binoculars. You can find a finder charts at https://s22380.pcdn.co/wp-content/uploads/WEB_UrNep_2019-2020_updated.pdf. Neptune (magnitude 7.9) is already up when the Sun sets near the Pisces/Aquarius border. Look near Φ Aquarii, a 4.2 magnitude star.
In the morning sky, Mars rises between 4-4:30am, three hours before sunrise. At magnitude +1.7, the only thing rivaling it in brightness will be the bluish star Spica, to the upper right of the planet. Look in the east-southeast. If you look early in the month, Mercury will be to the lower left of Mars, just coming off its second best morning view of the year. On the morning of December 1st, Mercury rises at 5:30am, 90 minutes ahead of the Sun and right about the time morning twilight begins. The two planets will separate throughout the month. A waning crescent Moon is above Mars on the morning of the 22nd. New Moon occurs on the 25th and then it zips into the evening sky. It is to the upper left of Saturn on the 27th and then is situated below Venus on the 28th in a beautiful site captured against the even-ing twilight.
December brings us the winter solstice. Winter begins as the Sun is perched over the Tropic of Capricorn on our Earth on De-cember 21st at 10:19pm CST. The noon sun is lowest on this day (26.5 degrees) and its rays are spread out over the Earth’s sur-face at our latitude. We also have about 9 hours and 20 minutes of daylight. More time for observing, eh? The Sun will undergo a annular or “ring eclipse” a few days later on the 26th, but the path crosses Saudi Arabia, southern India to Borneo. In other words, we won’t get to see it unless you can find a live stream online.
We should also mention the potent Geminid Mete-or Shower, peaking on the 13th and 14th of the month. The good news is, that’s a weekend. The bad news is, there’s a full Moon on the 11th! Thus the sky will be bright. Some say you could try observing early in the evening or just before the dawn so that the Moon is low in the sky. You could see anywhere from 30-80 meteors per hour. The Geminids rival the August Perseids though fewer watch the Geminids given the chill in the air.
-DCL