by Geoff Chester, USNO Public Affairs | 06 December 2022 Mars, 2022 December 5, 02:39 UT Imaged from Alexandria, Virginia The Moon courses her way through the bright stars if the Great Winter Circle, beaming down from nearly overhead as winter’s bright stars twinkle around her. Between Luna’s bright face, the dazzle of the planet Mars, and the colorful stars of winter’s signature constellations, the long winter nights aren’t quite so dark. Full Moon occurs on the 7th at 11:08 pm Eastern Standard Time. December’s Full Moon is popularly known as the Cold Moon in the Northern Hemisphere. Another popular name is the Moon Before Yule. Look for Luna just to the southeast of the Pleiades star cluster on the evening of the 6th. On the 10th she cozies up to Pollux, the brighter of the Twin Stars of Gemini. The center of attention this week is the red planet Mars. He reaches opposition on the 8th at 12:42 am EST, when Earth passes between him and the Sun. His dusty disc is 100 percent illuminated by the Sun, so he reaches the peak brightness that he will achieve during this apparition. His high northerly declination makes him an unmistakable sight, second only to giant Jupiter in the evening’s planetary parade. On the night of opposition he will rise at sunset and set at sunrise, providing ample time to view him in the telescope. Mars’ apparent disc is never very large, but his favorable placement for Northern Hemisphere observers means that we are looking through less of our atmosphere and its attendant turbulence. One’s first view of Mars is often very disappointing, appearing as little more than a small pink dot. However, careful viewing over several minutes will begin to show some of the planet’s darker surface features, which have tantalized Earthbound observers for centuries. A good six-inch telescope should show the planet’s white North Polar Hood, a huge weather system consisting of carbon dioxide clouds that shroud the north polar ice cap. As frustrating as it can be, viewing Mars is an almost unique experience in the solar system. Only the Moon and Mars give us a view of a solid surface not shrouded by atmospheric clouds. The features that can be glimpsed have been mapped by generations of astronomers and bear names that echo classic mythological realms. All of the attention on Mars almost overshadows the Full Moon, which tries to “get even” with the red planet by slipping in front of his ruddy disc on the evening of the 7th. Residents of the southeastern US will see a close appulse between the Moon and Mars. Here in Washington Luna passes a mere 2 arcminutes from the planet at 10:53 pm EST. Residents of the rest of the US and Canada will see Mars pass behind the Moon in what should be a very entertaining telescopic display. One thing to keep in mind if you do observe the event: the Moon is roughly half the size of Mars, but Mars is over 200,000 times farther away! If you have a clear view of the southwest horizon, go out half an hour after sunset to track down the bright glimmer of Venus, which is beginning to work her way back into the evening sky. She will be very low as the week begins, but each passing night she gets a bit farther from the Sun. If you have binoculars, look for the fainter glow of elusive Mercury about four degrees east of Venus. Both planets will become easier to see as the year reaches a close.