Highlights: December begins with a beautiful gathering of the night’s brightest objects in the southwest. Jupiter, Venus and the moon gather for a picturesque view shortly after sunset on December 1. Late in December you can also find some beautiful planet pairings in the southwestern sky. On December 28, Jupiter, Mercury and the thin crescent moon can be found low to the horizon as the sun sets. As the moon moves higher in the sky each subsequent evening, it will present us with a great pairing with bright Venus on New Year’s Eve. You may also still find Jupiter and Mercury together close to the horizon for a second pairing as we bid farewell to 2008.
Planets: Bright Jupiter has dominated the southern sky throughout the summer and fall but it soon will be lost in the glare of the sun as earth speeds to the opposite side of the sun from the giant planet. However, if you have a telescope or tripod mounted binoculars, you can still enjoy a few evenings of watching Jupiter’s four largest moons and their nightly dance around the king of planets. By taking this opportunity to view Jupiter and its moons you will be sharing in a special viewing that was first experienced by Galileo 400 years ago. 2009 has been designated as the international year of Astronomy by the United Nations and numerous events have been planned to commemorate 400 years of astronomy.
While Jupiter descends into the evening sky glow, Venus rises higher in the west each evening and dominates the evening sky for the next several months. A telescope or binoculars cannot reveal any surface detail on Venus because it is blanketed by a dense atmosphere of clouds. However, Venus catches our attention by being visible during the day – best located with binoculars and by its phases which are similar to the phases of our moon. In the months ahead, binoculars or a telescope will show Venus moving from a fat, “gibbous” phase to more of a crescent as it also increases in size. Saturn can be seen between midnight and dawn in the eastern sky although its rings are close to “edge on” and reflect less light to us on earth. Our planetary neighbour, Mars, is hidden behind the sun this month.
With December offering us long nights, it is an ideal time to step outside and enjoy the beautiful winter sky. The Pleiades star cluster appears in the east as darkness falls. Traditionally known as the Seven Sisters, you may be able to count seven visible stars but binoculars will reveal dozens of stars in this cluster. Did you know that the Japanese word for Pleiades is “Suburu?” Check the nameplate on one of these Japanese manufactured cars for a replica of the Pleiades star cluster. As Pleiades rises in the East, it is soon followed by the dominant winter constellation, Orion. With our long winter evenings, Orion will march across the southern sky throughout the winter months and finally disappear behind the sun after spring’s arrival.
On occasion astronomy offers the unexpected. In the early evening of November 20, thousands of people in Western Canada were treated to the view of a massive fireball that lit up the landscape. While this was an exceptional meteor, most clear dark evenings will offer a beautiful meteor streaking across our skies. In anticipation of a “falling star” I want to take this opportunity to wish you a wonderful Christmas holiday season along with best wishes for the International Year of Astronomy 2009. Clear skies.
Ken and his wife, Bev, offer regular public observing nights at their acreage near Didsbury, Alberta. Information on observing nights and further observing resources are available on their website, www.WhatsUpTonight.net or by calling them at 1-403-335-4857.