Monday, December 03, 2012

The Sky This Week - Thursday December 6 to Thursday December 13

The Last Quarter Moon is Friday December 7, New Moon is Thursday December 13. Mars is in Sagittarius. Jupiter is visible in the late evening sky. In the morning skies Venus is low on the horizon. Saturn is visible low in the morning sky not far from Venus. Saturn is visited by the Moon on the 11th, and Venus on the 12th.  Mercury is in the morning sky below Venus. Geminid meteor shower ramps up on the 13th.

Morning sky on Wednesday December 12 looking east as seen from Adelaide at 5:15 am local daylight saving time in South Australia. Saturn and Venus are drawing apart, Mercury is just on the horizon. The thin crescent Moon is between Venus and Mercury. Similar views will be seen elsewhere at the equivalent local time (click to embiggen).

The Last Quarter Moon is Friday December 7, New Moon is Thursday December 13.

Bright white Venus is now quite low above the eastern horizon,  and hard to see from cluttered horizons. Venus looks like a waxing Moon when seen through even a small telescope. Venus is in the constellation of Virgo.

Saturn is now visible above the eastern horizon before dawn. Saturn climbs higher in the morning sky and moves away from Venus during the week.

Mercury returns to the morning sky, but is difficult to see in the twilight below Venus. You will need a flat, unobscured horizon (like the ocean) to see it.

From the  10th to the 12th there is a nice line-up in the morning sky. On the 10th the crescent Moon, Saturn, Venus and Mercury are all in a line. On the 11th, the crescent Moon is between Saturn and Venus and on the 12th the crescent Moon is between Venus and Mercury. For the latter a clear unobstructed horizon is required.

Evening sky looking East as seen from Adelaide at 22:00 pm local daylight time on Saturday December 8. Similar views will be seen elsewhere at the equivalent local time.  Click to embiggen.

Mars is in the constellation  Sagittarius. Mars is now the brightest object in the western sky as the red star Antares, is lost in the twilight. Mars's distinctive red colour makes it relatively easy to spot.

Mars will be in binocular range of M22, one of the finest globular clusters in the sky, for most of the week.

Mars sets shortly after 9:30 pm local daylight saving time.

Mars was at opposition on March 4, when it was biggest and brightest as seen from Earth. Sadly, this is a poor opposition and Mars will be fairly small in modest telescopes.

Jupiter is visible all night long now, with opposition just passed on the 3rd. Jupiter is below the Hyades, near the red star Aldebaran. Jupiter moves slowly towards Aldebaran during the week, making it look as if the Bull has two eyes.

Jupiter, Aldebaran and the white star Rigel in Orion form a long line in the sky. With the Pleiades cluster and the constellation of Orion close by, this is a beautiful sight. 

Jupiter is easily seen in the late evening sky, rising around 8:00 pm local daylight saving time and is high by midnight. Now is a perfect time to observe Jupiter with a telescope of any size in the evening. Jupiters' Moons are easily seen in binoculars, and can be followed from night to night changing position.  

The radiant of the Geminid meteor shower above the northern horizon as seen from Adelaide on the morning of December 14 at 3:00 pm ACDST, similar views will be seen from other sites at equivalent local times. The radiant is marked with a cross (click to embiggen).

The Geminid Meteor shower is at its peak from the point of view of Australian's on the mornings of Friday 14 December (13 December UT) and Saturday 15 December but significant numbers should be seen on the 13th. The best time to observe is between 1 and 4 am (daylight saving time, 12-3 am non-daylight saving time), with the highest rates between 2-3 am daylight saving time.

With the Moon out of the picture in Australia we should see roughly a meteor every 2 minutes.

You can check predictions for you local site with the NASA meteor flux estimator (scroll down to 4 Geminids in the SHOWER box, make sure you have your location and date correct as well)..

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 AEDST, Western sky at 10 pm AEDST. For further details and more information on what's up in the sky, see Southern Skywatch.

Cloud cover predictions can be found at SkippySky.