Have you ever gazed at the night sky and wondered … what’s that bright star? And what is the name of that constellation that looks like a big square … and how come the moon looks different each night? 
 
Well, September is a great month to become an amateur astronomer! Grab a pair of binoculars and read this guide to the starry heavens for this month. If you would like to know more about what to spot each month, then visit John's Skynotes. 
 
As the first golden hints of autumn appear (and the kids go back to school), the dark nights are returning and with it the chance to observe our solar system and galaxy. 
 
After the short nights of summer, the darker hours lengthen and you can revel in seeing all sorts of nocturnal niceties. One of these is the Zodiacal Light. What’s that, we hear you ask? 
 
The Zodiacal Light is a beautiful cone of light illuminated by the sun from below the horizon, and it appears in the night sky only at certain times of year. This month, you can best observe it between 10th and 24th and usually around 3.30am, before the arrival of dawn. This mysterious dusty light points southwards at a steep 60-degree angle and is made of the dust that helped form our solar system. Worth looking for if you happen to be awake or even set your alarm to get you out of bed. Look towards the east and it is worth noting the Zodiacal Light has the same light intensity as that of the Milky Way, so it is faint and you need to be away from street lights. 
 
The moon is a constant companion for those of us who find it hard to sleep, or if you love watching the heavens. This month the moon at apogee, or its farthest from the earth, on 20th September and is at perigee, or nearest to our planet, on 8th September. The next day, there is a new moon, and the full moon will shine on the 25th. In the days when full moons were given names, this is the second 'Harvest Moon' of the year, the last one was in August. 
Of course, the planets are our next nearest neighbours, and there are five that can be easily spotted with the naked eye. Mercury is the planet closest to the sun, and is one that can be hard to spot given its orbit is so close to our nearest star. This small planet can be seen during the first week of September about one and a half hours before sunrise in the east. Use binoculars to spot Mercury, low in the growing eastern twilight. 
 
Venus, often called Earth’s twin, is one of the brightest objects in the sky and sets an hour after the sun sinks below the horizon. Grab your binoculars and you’ll see that planet as a very thin yet elegant crescent in the west-southwest. 
 
Venus is very close to the horizon in the bright evening twilight so you need a clear, low horizon in that direction. 
 
During September, Mars, the red planet, is even brighter than Sirius, which is one of the brightest stars in the heavens and can be seen during the first half of the month in the late evening in the south west. 
 
The planet is fading, having been at its brightest and closest at the end of July, but it is still slightly brighter than Sirius, the brightest true star in the sky! Mars looks like a red beacon low in the southwest. 
The gas giants of Jupiter and Saturn are also visible to the naked eye. Jupiter is our solar system’s largest planet and can be seen in the low southwest sky in the early evening. If you have binoculars, you can maybe see some of its moons too. Jupiter is becoming difficult to observe as it is 'running’ into evening twilight. Saturn, the wonderful ringed planet, is also visible in the middle of the month, has a yellow tinge and is one of the most tantalising treasures in terms of night time spots. Saturn is very low in the evening twilight also. You will need a small telescope to see its 'rings' in the turbulent sky of the near-horizon! 
 
September is also the month in which the autumnal equinox takes place, this year on 23rd September. This is when the hours of light and dark are of the same length. After this date, we gradually lose daylight as we head towards the shortest day.  
 
We would like to thank John Harper for his wonderful help with this article and for allowing us to use some of his graphics. Find out more here!  
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