Sunday, September 9, 2012

Astronomy: The September Night Sky

Here are some objects for the unaided eye for the month of September. All of these objects, although small, should be visible without the help of binoculars or a telescope, so long as you have clear dark skies. If you do have a pair of binoculars, or a small telescope you can enhance many of these views.

Light pollution is a killer for seeing these objects with your unaided eye. To find out how dark your location is, use the Google Map Overlay of light pollution. If you are in a blue, gray or black area then you should have dark enough skies. You may still be able to see some of these objects in a green location. If you aren’t in a dark sky location you may still be able to see these objects with a pair of binoculars or telescope.

You can find help locating the night sky objects listed below by using one of the free sky charts at (scroll down to Northern Hemisphere Edition and click on the PDF for September 2012).

If you are not familiar with what you see in the night sky, this is a great opportunity to step outside, look up, and begin learning the constellations. The sky is beautiful and filled with many treasures just waiting for you to discover them. Once you have looked for these objects go through the list again if you have a pair of binoculars handy, the views get better!

Measuring Degrees with your hands, proportionally works for people of all ages. With your arm fully extended out:

Width of your pinky finger is 1°

Width of your ring, middle, and index finger equals 5°

Width of your fist equals 10°

Width from tip to tip of index finger and pinky finger stretched out equals 15°

Width from tip to tip of your thumb and pinky finger stretched out equals 25°

Highlight for viewing with the unaided eye

During the moonless nights of September 9th into the morning of the 10th is a small meteor shower known as the Epsilon Perseids. This meteor shower is a particularly new one discovered in 2008 where they radiate from the constellation Perseus. This meteor shower isn’t nearly as active as the August Perseids, but should produce around 5-10 meteors per hour. Since it is relatively knew there isn’t a great prediction of this meteor shower, and we will only know how it goes if we go out and look.

If you do go out and see any meteors emanating from Perseus please leave a comment below about the time you were out, and how many meteors you saw. I will see if there is a way to submit the data from everyone to NASA to help get more information from this meteor shower.

There is also a NASA app available on iTunes (not sure about Android, but may be worth a look for those with an Android phone) called “Meteor Counter” where you start it when you go out, and you can record the meteors as you see them. When you’re viewing session is done the data is automatically uploaded to NASA researchers for analysis. I would still like to see if anyone has any results from the Epsilon Perseids via the comment section below, provided we have clear skies the night of the 9th.

The Moon

September 12 – The Moon passes 4° south of Venus

September 15 – New Moon. Get out and enjoy a moon free night!

September 18 – The Moon passes 0.8° south of the star Spica in Virgo, and is 5° south of Saturn. Also the moon will be at perigee (227,268 miles from Earth)

September 19 – The Moon passes 0.2° south of Mars

September 22 – First Quarter Moon, also autumnal equinox.

September 23 – The Moon passes 0.4° south of the dwarf planet Pluto (which is not visible with the unaided eye or binoculars)

September 29 – Full Moon

September 30 – The moon passes 1.8° north of Spica


Our innermost planet makes an appearance, although quite low for us here above 40° latitude. Mercury will only be 2° above the horizon and will require a very flat horizon to find it to the west after sunset. Seeing as we are in a mountainous area we may be out of luck spotting Mercury this month.


If you can stay up late enough, or wake up early enough you can find Venus rising in the east at 3am in the constellation, Gemini. Lying 9° south of the 1st-magnitude star Pollux (the head of one of the twins of Gemini) will be Venus shining at magnitude -4.3; Venus will outshine Pollux by more than 100 times. Very early in the month Venus will move from Gemini to the constellation Cancer.

On September 12 there will be a beautiful alignment of a waning crescent Moon lying 4° southwest of Venus, and Venus will be 3° southwest of the open cluster M44 – The Beehive Cluster in the constellation, Cancer. Should be visible with the unaided eye especially if you have dark enough skies.

If you have a pair of binoculars you should be able to see Venus and the Beehive cluster in the same view making for an interesting sight to see through your binoculars.


Only 10° to the east of Saturn is Mars, still holding onto the night sky. Mars and Saturn wont stay close for long as Mars rapidly heads eastward from the constellation Virgo into Libra. On the 15th of September Mars passes close to a double star in Libra, Zubenelgenubi (one of my favorite star names in the sky, try and say it 5 times fast). Unfortunately Mars is small enough and far enough from Earth that it’s views are not very impressive through a telescope, and definitely less impressive through a pair of binoculars.


Within the constellation of Taurus you can find the dazzling bright Jupiter. Rising just before midnight in early September it’s a great site to view as it lies near the bright red star Aldebaran (the eye of the bull), and 10° northeast of the open cluster Hyades in Taurus.

I do urge anyone with a pair of binoculars to get them out and have a look at Jupiter. You may not be able to pull out the details of the cloud bands, or even the great red spot, but you will be able to see at least 4 of Jupiter’s moons. If you see any less than that it is because whatever ones are missing are either behind or in front of Jupiter.


Take the beginning of September to say goodbye to Saturn until next year. Saturn lies only about 10° above the horizon after sunset, and will be below the horizon by October, and passing behind the sun in late October. You wont have to wait long for Saturn to return, only a few weeks, but it will be early in the morning that you can find it.

 Photo Above: Messier 31, also known as the Andromeda Galaxy through my telescope by Michael Rector

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Although he now lives in Clinton County, amateur astronomer Michael Rector has fond memories of spending time at Great Sacandaga and West Canada Lake where the skies are dark and the Milky Way is bright.

Michael writes about astronomy on his own blog Adirondack Astronomy and is interested in getting together with other star-gazers around the region. If you are interested in getting together for an occasional star party feel free to contact him at


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