The month begins with the thin crescent waning moon in the early morning sky next to Mars. New moon is Oct, 4, and the moon is full Oct. 18. In rapid succession, Mercury and Saturn Oct. 6, and Venus Oct. 8 are in close proximity to the waxing crescent of our satellite in evening twilight. Oct. 12, minor planet Juno is within a degree for North American viewers - it's an occultation when seen from Antarctica - the moon passes in front of the tiny object. Jupiter shares the late-evening sky with the moon Oct. 25, and Mars rejoins it Oct. 29.
Mercury is an evening object, but a tough one to see, since it hugs the horizon right at sundown. Binoculars are likely a must, if the fleet planet is to be seen. Saturn is right above Mercury for the first 10 days of October, which should be a good finder/helper.
Venus is also low to the horizon, owing to the angle of the ecliptic, but higher in the sky than Mercury. Also, because of its extreme brightness, Venus is an easy find, a few degrees to the east of Mercury. Watch for the crescent moon nearby Oct. 8.
Mars rises in the east shortly after 2:30 a.m., with the thin crescent moon nearby, and not far from the bright star Regulus, in the constellation Leo, The Lion. About the same time as Mars appears, the bright star Sirius - brightest star in the night sky - rises a few degrees to the west. The moon hovers close by at the end of the month.
Jupiter rises in the east ahead of Mars by a couple of hours in the constellation Gemini, the twins. Off to the west of the giant planet are the bright stars of the Pleiades, the Hyades, and Orion, all standing in a row from the horizon halfway to the zenith.
As Saturn nears conjunction with the sun, it will soon be lost in the solar glare. Watch for the ringed planet near Mercury during the opening days of October.
Uranus and Neptune rise near sundown and cross the sky all night, setting at five and four o'clock, respectively.
Watch for the Zodiacal Light in the morning eastern sky before daybreak during the first two weeks of October.
- 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 editor's assistant and a contributor to Observer's Handbook, production manager of the bi-monthly RASC Journal and the society's national secretary. He was given the RASC Service Award at the 2012 general assembly in Edmonton.
