Monday, December 10, 2018
The Sky This Week - Thursday December 13 to Thursday December 20
The First Quarter Moon is Saturday, December 15.
Similar views will be seen elsewhere in Australia at the equivalent local time (30 minutes before sunrise)
Similar views will be seen throughout Australia at the equivalent local time (60 minutes after sunset, click to embiggen).
Comet 46P is rapidly brightening and is roughly magnitude 4.5 now, readily seen as a fuzzy blob in binoculars. Is bright enough to (just) see with the unaided eye under dark sky conditions and is brightest this week, between the 13th and the 16th of December. The comet is closest to the Earth on the 16th, but you may wish to wait until the Moon sets on the morning of the 17th to see the comet at its best. More details on how to see it, along with charts suitable for printing, are here.
Mira (omicron ceti), a star in the constellation of Cetus the whale, is a red giant that pulsates over a period of about 331 days and changes brightness from below naked eye visibility to a peak of round magnitude 2 (roughly as bright as gamma Crucis in the Southern Cross) in around 330 days. Mira is at past peak magnitude this week, but may stay bright the rest of this month. Following a line drawn between Sirus and Rigel will bring you to Mira.
Geminids as seen from Brisbane facing north at 2:00 am AEST on the morning of Saturday December 15. The Geminid radiant is marked with a starburst. (similar views from elsewhere at equivalent local time eg Sydney 3:00 am AEDST, Adelaide 3:30 am, click to embiggen).
The Geminids are a fairly reliable meteor shower and this will be a good year for them with little moon interference.
The radiant doesn't rise until just before midnight (daylight saving time) in most of Australia, so you will still have to disturb your sleep for this one. The peak is on the morning of Saturday the 15th when Australians should see a meteor every one to two minutes under dark skies in the early morning of the 15th, between 1:00 am and 4:00 am local time. The further north you are the better the meteor rates. You can find predictions for your local site at the meteor flux estimator (choose 4 Geminids and date 14-15 December, don't forget to change the year to 2018). For more details see my Geminid page.
Venus climbs higher in the morning skies.
Mercury is low in the morning twilight.
Jupiter is returns to the morning sky but is low in the twilight.
Mars is in Capricornius and is readily seen in the evening. Mars is now rapidly dimming and shrinking. When Sirius rises Mars is no longer the brightest object in the night sky aside from the Moon. In a telescope the "gibbous" shape of Mars will be obvious. Mars is close to the First Quarter Moon on the 15th.
Saturn is lost in the twilight..
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