By Deane Morrison, University of Minnesota News Service
It's no accident that holidays featuring lights are celebrated in December. This month Venus and Jupiter—and possibly one comet—crank up the wattage for us.
In early December, Venus shines as bright as it ever gets. Hanging like a lantern over the sunset horizon, our brilliant sister planet begins the month as a thick crescent, its face about 30 percent lit. By the end of the month, the crescent has lengthened considerably and thinned to a mere 5 percent of the planet's disk. These changes happen because Venus is circling in for its next pass in front of the sun; soon it will drop from the evening sky.