The Enterprise - White Salmon, Washington

What's in the sky

December stargazing

November 27, 2012

December skies give us plenty to look at this year, on those rare occasions when the clouds part. Jupiter's opposition, the Geminid Meteor shower, and the arrival of winter constellations in the evening sky will make it worthwhile to brave the cold on clear nights.

The month begins with a very cool sight, low in the southeast, on the morning of Dec. 1. If skies are clear and you have a good view to the southeast, look for the planets Mercury, Venus, and Saturn to be almost perfectly aligned, low in the sky. Look between 6:30 a.m. and daylight.

Venus will be quite apparent -- it is the brightest object in the night sky, except for the Moon. Look above and to the right of Venus for a bright "star" -- the planet Saturn. Elusive Mercury will be below and to the left of Venus, a bit brighter than Saturn. By 7 a.m., they should all still be visible, a bit higher in the brightening sky.

The solar system's giant, Jupiter, makes its closest approach to Earth for 2012 on Dec. 2. On that day, the Earth will be right between the Sun and Jupiter, so the gas giant will be opposite the Sun from the Earth. Hence the term "opposition" for the event.

Jupiter will rise at sunset, will be directly south at midnight, and will set when the Sun rises. At the start of the month, Jupiter will be located between the "horns" of Taurus the Bull, near the Bull's blood-red eye, the star Aldebaran.

During the month, Jupiter will move away from Aldebaran and closer to the bright star cluster Pleiades. If you get a couple of peeks at it during the month, note its movement relative to the background stars.

The Geminid meteor shower peaks on the night of Dec. 13-14. This year the Moon will be new, and thus skies will be dark for the best view. The Geminids can produce 50 meteors per hour. The best time is after midnight. Try taking them in during early morning hours if you can get up and brave the cold! One interesting fact about the Geminid shower is that the meteors originate from an asteroid, rather than a comet.

December begins with a waning gibbous Moon, which will rise at about 8 p.m. On Dec. 9, the Moon will be located just below the star Spica, in the eastern morning sky. After new Moon, on Dec. 13, Earth's satellite will march across the evening sky, each night being located a bit further east amongst the background stars. The Moon will be full on Dec. 28.

On Christmas Eve, look for the Moon just below the bright star cluster Pleiades, and just above bright Jupiter and the bright star Aldebaran. It should be an impressive sight. You may need a pair of binoculars to spot the cluster, which will be drowned out by the bright, almost full Moon. If skies are clear, do a little stargazing while you watch for Santa in the night sky!