The Sky This Week - Thursday September 11 to Thursday September 18

The Last Quarter Moon is Tuesday September 16. Mercury climbs towards the bright star Spica. Mars and Saturn are prominent in the evening sky forming a line with Mercury and two bright stars. Jupiter becomes more prominent in the morning sky. Comets C/2013 A1 Siding Spring and C/2013 V5 are in the reach of small telescopes.
 
The Last Quarter Moon is Tuesday September 16.

Evening sky on Saturday September 13 looking west as seen from Adelaide at 19:00 (7:00 pm) ACST in South Australia. Mercury is now reasonably high above the horizon in the early evening. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Mercury climbs higher in the evening sky and is now readily visible above the western horizon. It is now easy to see from half an hour after sunset to  an hour and a half after sunset, when the  zippy planet is in dark skies.

The western horizon now has a long string of bright objects making an interesting line in the sky. Mercury, Spica, Saturn, Mars and Antares. The line is topped off by the hook that is the tail of the Scorpion, embeed with clusters and nebula.

Mercury is climbing rapidly in the sky, coming closer to Spica, next week they will be less than a finger-width apart. 

Evening sky on Saturday September 13 looking west as seen from Adelaide at 22:00 (10:00 pm) ACST in South Australia. Mars and Saturn are  under the head of  Scorpius. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Mars  is easily seen in the western evening sky, setting just before midnight. Mars was at opposition, when it is biggest and brightest, on the 9th of April, and is still  readily distinguishable as the bright red/orange object above the western horizon in the early evening.

Mars is in the constellation of  Scorpius. It forms a line with the red star Antares (which means rival of Mars) and Saturn (and Spica and Mercury). Over the week Mars draws close to the head of the Scorpion. By the end of the week it is close to the middle star of the Scorpions head, Dschubba.

Saturn is in the early western evening sky, and was at opposition on June 11th. Saturn is visible most of the evening. Saturn is high enough from twilight for decent telescopic observation for a few hours and sets just before 11pm local time.

Saturn is in Libra near the head of the constellation of the Scorpion and forms a  line with Mercury, Spica, Mars and Antares.

Morning sky on Saturday September 13 looking north-east as seen from Adelaide at 5:30 am ACST.  Jupiter is above the horizon and comet C/2013 V5 is roughly between Procyon and Sirius. (click to embiggen).

Venus is lost in the glare of the Sun.

 Jupiter  rises higher in the morning twilight, and now is easy to see above the horizon at twilight. During the week Jupiter climbs higher and becomes easier to see as the brightest object above the north-eastern horizon.

Comet C/2013 V5 is brightening and may become visible to the unaided eye (just) later in the month. Now you may need a small telescope to see it. Although it is magnitude 6.6 and should currently be visible in binoculars, its diffuse nature and the light of the waning Moon may make it difficult to see over the next few days. 

 Evening sky on Saturday September 13 looking South as seen from Adelaide at 22:00 (10:00 pm) ACST in South Australia. Comet C/2013 A1 Siding Spring is above the Southern Cross, heading for the tail of the Scorpion. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

Comet C/2013 A1 Siding Spring is rising higher the the evening sky, being highest around midnight. It is currently located just above the  Southern Cross. While at magnitude 8.4 it should be visible in binoculars, it is likely that you will need a small telescope to see it until the waning Moon leaves the evening sky early in the week.

There are lots of interesting things in the sky to view with a telescope. Especially with Mars and  Saturn  prominent in the early evening sky.  If you don’t have a telescope, now is a good time to visit one of your local astronomical societies open nights or the local planetariums.