Tuesday, September 13, 2016
The Sky This Week - Thursday September 15 to Thursday September 22
The Full Moon is Saturday September 17. There is a penumbral eclipse of the Moon in the early morning of the 17th. The Moon is at Perigee (when it sis closest to the Earth) on the 19th).
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 below to the bright star Spica, the brightest star in the constellation of Virgo. Venus comes closer and is closest to Spica on the evenings of the 18th and 19th.
From the 16th to the 21st there is a series of bright passes of the International space Station to the bright planets, with some notable ISS-Venus passes, details are here.
Jupiter is lost in the twilight.
Mercury is lost in the twilight.
Mars is in the western evening skies in the body of the Scorpion (strictly, it is in the constellation of Ophiuchus, as is Saturn).
Mars moves further down the body of the Scorpion this week, moving away from Saturn and the red star Antares. The triangle they form continues to lengthen.
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.
Morning sky on Saturday September 17 looking west as seen from Adelaide at 04:00 ACST. Similar views will be seen elsewhere in Australia at the equivalent local time. (click to embiggen). Note the subtle darkening of the Moon.
On the morning of 17 September there is a penumbral eclipse of the Moon, where the Moon glides through the outer segment of the shadow cast by Earth. There will be a faint, but visible, darkening of the Moons northern regions.
Unfortunately, this all occurs in the early morning, so you will need to get up in the early hours to see it. However, to eclipse aficionados the subtle darkening of the Moons bright light to a pearly glow is quiet beautiful.
All of Australia will see this penumbral eclipse from start to maximum. However, in the eastern states the Moon sets before the eclipse finishes. More importantly, in the eastern states astronomical twilight begins around maximum, so the faint penumbral shadow will be washed out by the twilight glow about an hour before the Moon sets. Central states have around half an hour more time before the eclipse will be washed out.
For the East Coast Moon the eclipse begins at 2:52 am AEST, astronomical twilight 4:30 am (approx), maximum eclipse is at 4:54 am , the eclipse ends at 6:56 am after Moonset.
For the Central states the eclipse begins at 2:23 am ACST, astronomical twilight 4:48 am (approx), maximum eclipse is at 4:24 am , the eclipse ends at 6:23 am around Moonset.
For Western Australia the eclipse begins at 0:53 am AWST, astronomical twilight 4:52 am (approx), maximum eclipse is at 2:54 am , the eclipse ends at 4:56 am
See here for a map and contact timings in UT for sites outside Australia
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