Jupiter, Saturn and Venus have lined up in the evening sky and will continue to be prominent features throughout most of December, but this week, the trio will get a visitor. The easy-to-find planets, paired with the approaching peak of the Geminid meteor shower, make December a great month for evening stargazing. The only caveat is that the weather can be fickle during the long December nights, often offering frosty conditions on nights that are not cloudy. The moon started off the week next to Venus, and as the week progresses, it will continue to move up the chain, passing...