Tuesday, September 20, 2016
The Sky This Week - Thursday September 22 to Thursday September 29
The Last Quarter Moon is Friday September 23. Earth is at Equinox on the 23rd, when day and night are approximately equal length.
Venus continues to rise into darker skies this week. Venus is high in the dusk sky and can be seen easily. From a little before half an hour to a bit after an hour and a half after sunset to just under an hour after sunset, Venus is easily seen, staying visible after twilight is over low above the horizon but in truly dark skies.
At the start of the week Venus is just above the bright star Spica, the brightest star in the constellation of Virgo. As the week goes by Venus climbs higher into the evening sky away from Spica and towards the head of the Scorpion.
Jupiter is lost in the twilight.
Mars is in the western evening skies near the body of the Scorpion. On the 22nd it officially enters Sagittarius and comes within binocular range of two glorious nebula, the Lagoon Nebula and the Triffid Nebula. It is also just within binocular range of the Butterfly cluster at this time. With the Moon out of the way watching Mars progress through the star fields of Sagittarius will be delightful.
As the week progresses Mars comes closer to the Lagoon nebula and is closest on the 28th and 29th. People with wide field telescope lenses will just fit Mars and the Lagoon nebula in them together. at this time.
Mars was at opposition on May 22, and is still visibly dimming, but is still a modest telescope object. It is visible all evening long. In even small telescopes Mars will be a visible, but gibbous, disk, and you may even be able to see its markings.
Saturn was at opposition on the 3rd of June. However, Saturn's change in size and brightness is nowhere near as spectacular as Mars's, and Saturn will be a reasonable telescopic object for many weeks. Saturn is reasonably high in the evening sky and is readily visible next to Scorpius. Saturn is still high enough for good telescopic observation in the evening. In even small telescopes its distinctive rings are obvious.
Mercury returns to the morning sky in the last week of September but never rises far above the horizon. On the 29th there is a chance to use the thin crescent Moon as a guide to finding Mercury low in the twilight.
Other morning views will be the close approach of the waning Moon to the bright red star Aldebaran in the head of Taurus the Bull on the morning of the 22nd, and the close approach of the thin crescent Moon to the bright star Regulus, alpha Leonis on the morning of the 28th.
There are lots of interesting things in the sky to view with a telescope. 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.
Printable PDF maps of the Eastern sky at 10 pm AEST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.
Cloud cover predictions can be found at SkippySky.
Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/
Labels: weekly sky