Highlights: Mars is the focus this month. Reaching opposition on December 8, the red planet rises at sunset, sets at sunrise and shines far in the south at midnight as a strikingly bright orange star. Opposition always means closest proximity to earth. Mars will reach it on December 1st at a distance of 81.5 million kilometers. Dark structures appear on the tiny planetary disc through the telescope – extensive areas in which layers of rock shimmer through the reddish dust of Mars. In addition, the bright polar caps can be seen, because Mars has seasons like Earth. Because the planet will experience the equinox on December 26, both the north and south polar caps can now be seen. They consist of water and carbon dioxide ice. A rare spectacle occurs on the morning of December 8: the eastern edge of the full moon will occult Mars just after 6 am, gradually dying out over about 35 seconds. Less than an hour later, the planet slowly reappears on the opposite western edge of the moon. Although the spectacle above the western horizon can be followed with the naked eye, it is much more impressive in binoculars or telescopes.
Graphic: M. Rothe
Stars and constellations: Winter is approaching in the sky: Orion has risen in the southeast, the stars of Taurus and the triangularly arranged Pleiades are twinkling above. High in the south-west is the winged horse Pegasus, to which is attached the chain of stars of Andromeda. Fomalhaut sparkles deep in the southwest. The Big Dipper’s tiller is pointing pretty much exactly to the north point on the horizon. In the north-west, the stars Deneb in the Swan and Vega in the Lyre shine, in the north-east the bright Kapella in the Fuhrmann and the twins Castor and Pollux attract attention.
Planets, moon, meteors: Mercury can be spied low over the southwestern horizon for about 20 minutes after 5 p.m. at the end of the month. Around the same time Venus also appears there and begins her appearance as the evening star. Also visible in the sky are Mars in Taurus, Jupiter in Pisces and – in the evening hours – Saturn in Capricorn. Full moon is December 8th, last quarter December 16th, new moon December 23rd and first quarter December 30th. Watch out for shooting stars on December 13th and 14th. The Geminids could conjure up 120 meteors per hour, including some very bright ones. The astronomical winter begins on December 21 at 10:48 p.m.