The month begins with the moon in the last Quarter, meaning it has been about 22 days since new moon. New moon occurs Oct. 7 and it is full Oct. 22. Watch for Venus only three degrees away from the moon Oct. 9; a close brush through the Seven Sisters (Pleiades) Oct. 25; and the cluster M35 is only 0.7 degrees away Oct. 27.
Mercury may be visible in the morning sky early in the month, but quickly fades as it rounds behind the sun.
Venus is diving into position (inferior conjunction) in front of the sun, but is still visible for the first week or more. You may catch a glimpse of the crescent moon close by the bright planet Oct. 9.
Mars is very low in the western sky - probably not visible except with optical aid (binoculars or a small telescope).
If you've been wondering about that bright object in the east at sunset, it is the giant planet Jupiter. It rises high in the sky to be almost directly overhead during the late evening. This is the best time for viewing, as there is less atmosphere between viewer and planet, and therefore less distortion. A challenge during this particular part of Jupiter's orbit (relatively close to Earth) is viewing the Galilean moons without any optical aid - using the naked eye only. The two inner moons are virtually impossible, because they are just too close to the bright glare of the planet, but the outer two, Callisto and Ganymede, should be visible at times.
The evening of Oct. 6 presents a great opportunity to view Callisto this way. Position yourself behind a pole or tree so as to block the light of the planet, then look for the small moon close by. It can be done!
Saturn is still behind the sun as the month opens, but will become visible as a morning object towards the latter half of October.
Uranus is visible most of each night during October, rising at sundown, crossing the meridian (straight south) near midnight, and setting in the morning.
Neptune is well placed in the evening sky, but requires the use of a telescope or good binoculars to view it.
The Zodiacal Light is usually visible in the east before morning twilight for the first half of the month. Dust in orbit around in the elliptical plane shows up when backlit by the sun as a very large pyramid shape.
- James Edgar has had an interest in the night sky all his life. He joined the Royal Astronomical Society of Canada in 2000. He is editor's assistant and a contributor to the Observer's Handbook, production manager of the bi-monthly RASC Journal, and is the society's national secretary.
