The moon is at last quarter Jan. 1, meaning that it is all the way through its earthly orbit. Thus 12.2 degrees of eastward motion per day times 22 days equals about 268 degrees. That’s a rough estimate, but very close to 270 degrees, leaving about 90 degrees left to complete the orbit of 360 degrees.
Jan. 3, Mars is less than two degrees south of the moon, likewise for Venus and Saturn. Jan. 6, both are within three degrees. New moon is Jan. 9. On Jan. 19, Aldebaran, the bright star in Taurus, the bull, is occulted by the moon as it passes in front of the star. This is visible for all of North America in the evening sky. The full moon occurs Jan. 24. Jupiter is very close Jan. 27.
Mercury puts on a show in the western evening sky, well placed for northern observers. Toward month end, the speedy planet has moved west of the sun and appears in the morning sky.
Venus continues as the Morning Star in the eastern dawn sky. Watch for a close conjunction with Saturn Jan. 9.
Mars begins the month rising shortly after midnight and rising higher in the sky until the light of dawn obliterates our view of the Red Planet.
Jupiter appears in the east just before midnight, rising before Mars and disappearing in the same way as dawn brightens the sky. Jan. 9, the gas giant begins retrograde motion, appearing to move westward against the starry background. This apparent “backward” motion is a result of Earth orbiting faster than the outer planets. This was a source of much head scratching for early astronomers, which was finally resolved when Copernicus, Kepler and Galileo proposed a sun-centred Solar System, rather than a geocentric one.
Saturn is in the little-known constellation Ophiuchus, rising in the dawn sky before the sun. Observers will have to be quick if they want to spot the Ringed Planet, as sunrise comes quickly to blot it out.
Uranus sets late in the western evening sky.
Neptune is low in the western sky at dusk. This telescopic object is far away from us, orbiting at an average distance of 30 astronomical units — 30 times the distance from the sun to the Earth.
The Quadrantid meteor shower peaks Jan. 4, early in the morning.
— James Edgar has had an interest in the night sky all his life. He joined The Royal Astronomical Society of Canada in 2000 and is now the Society’s president, assistant editor and a contributor to the renowned Observer’s Handbook, and production manager of the bi-monthly RASC Journal. He was given the RASC Service Award at the 2012 General Assembly in Edmonton.
