December starts with a waxing gibbous moon well on its way up as the sun sets. Meanwhile, Saturn and Mercury are close together in the west setting together. Many of the favorite winter constellations rise during the night. But it is well after midnight before we see any more planets. Mars rises next to Spica in Virgo, followed by Jupiter a little below them. And if you’re lucky, you can catch Venus in the dawn’s light.
Saturn and Mercury get harder to see, sinking into the sunset during the next week or so. By mid-month, don’t count on finding them. Mars, meanwhile, has begun to sink below Virgo as it heads toward Jupiter. Jupiter is inching closer to Zubenelgenubi and then into the diamond of Libra. Mars and Jupiter will have a very close conjunction within it next month. Start watching them now!
Venus is heading sunward in the morning sky. You won’t see it anymore by the end of the month, but you may catch Saturn after conjunction in the morning sky. If not, wait until a better view in the new year. Mercury, almost as quickly as it has vanished from the evening sky, has reappeared in the morning sky in the second half of December. Look for a thin sliver of a moon to be next to it on the 17th. As though it’s a Christmas gift, the messenger planet is easiest to see around the 25th.