For casual stargazing, the most rewarding part of the sky this month lies to the east and southeast in the early hours before the Sun rises. There’s so much to see here, especially from December 5-8, you need to start early before the sky brightens. The simulation below, from Stellarium, shows you what to look for.
At the eastern end of this long chain, you find the planet Venus, the brightest object of this morning congregation. The planet shines at magnitude -4.2 and presents a 17″-wide disk about 2/3 illuminated when viewed in a telescope. The planet is slowly getting fainter and moves back towards the rising Sun as December progresses.
Venus guides your way from December 6-10 to Comet C/2013 US10 (Catalina). The comet will lie about 5° east of Venus during these days, though it will move northward slightly from day to day on a beeline towards the bright star Arcturus on January 1, 2016. A pair of binoculars will make the comet plainly visible in the same field of view as the bright planet. The slender waning crescent Moon will also lie within a single binocular field of Venus and the comet on Dec. 7. It might make for a good photo-op as well.
West of Venus and the comet, you will find the icy-white giant star Spica, the brightest star in the constellation Virgo. Not far to the northwest of Spica, look for the steady ochre dot that is the planet Mars. It’s just a little fainter than Spica this month, and it’s not much to look at in a telescope, but Mars will slowly brighten and grow larger on its way to opposition next May.
Finally, far to the northwest, look for the the brilliant planet Jupiter. Brighter than any star and outshone only by Venus this month, Jupiter is also getting larger each day as the Earth catches up to the big planet on its inside track around the Sun. Jupiter reaches opposition in 3 months, but it’s already worth inspecting in a telescope.