The Monthly Sky for December 2016

by Viktor Zsohar

Explore the Universe!

The Yukon is blessed with longer and longer nights during the winter months, and with hues of the Aurora Borealis in November. Members of the RASC: Yukon Centre have started to take advantage of the clear and dark skies that December has to offer at our new observation site: Takhini Hot Springs!The concrete pad of the observatory was constructed with generous contributions, while the observatory dome is still waiting for a revamp and a future grand opening. This means that we can start using our observatory site for ‘members only’ observation sessions right away!

As introduced by the previous Monthly Sky, the Explore the Universe Certification is available for all our members. In addition, the RASC: Yukon Centre has the privilege of announcing that our Society is now certified to issue “Explore the Universe” certifications locally!

If you plan to represent the Society at any public outreaches and/or future astronomy tours, or you just fell in love in the sky… this certification is for you. For the Society, it demonstrates that you are a certified observer and ready for more challenges in discovering the Universe!

One of the special features of this program is that it can be completed entirely using binoculars and/or the unaided eye. A choice of objects is provided so that you can start the program at any time of the year, and easily complete the requirements within three to six months. Application and recording forms are available on-line @

Our AGM is at hand!
ON DECEMBER 05th, 2016
ROOM A2402

Learn about our finances!
Election of the Board of Directors for 2017!
Cast your vote!
Sign-up for committees!


December Yukon Sky Events

Dec  1.     Algol at minimum. Mercury is at greatest heliocentric latitude South.
Dec  3.     Vesta stationary. Venus 6° South of Moon, Mercury nearby.
Dec  4.     Algol at minimum
Dec  6.     Neptune 0.7° South of Moon, occultation at daytime. Not visible in the Yukon.
Dec  7.     First quarter. Algol at minimum.
Dec 10.    Algol at minimum. Saturn in conjunction with the Sun.
Dec 11.    Mercury greatest elongation East 21°
Dec 12.    Moon at perigee, large tides
Dec 13.    Aldebaran 0.5° South of Moon, occultation during daytime. Algol at minimum.
Dec 14.    Full Moon. Geminid meteors peak.
Dec 15.    Ceres stationary
Dec 16.    Algol at minimum
Dec 18.    Regulus 1.0° North of Moon. Occultation not visible in the Yukon
Dec 19.    Algol at minimum. Mercury stationary and then at ascending mode.
Dec 21.    Last Quarter. Winter Solstice.
Dec 22.    Ursid meteors peak. Jupiter 2° South of Moon.
Dec 24.     Algol at minimum
Dec 25.    Mercury at perihelion. Moon at apogee.
Dec 27.    Algol at minimum
Dec 28.    Jupiter at greatest heliocentric Latitude North. Mercury in inferior conjunction.
Dec 29.    New Moon. Uranus stationary
Dec 30.    Algol at minimum

Solar System


Mercury is well placed in the evening twilight, reaching greatest elongation on the 11th (21° E), then in perihelion on December 25th, and inferior conjunction on the 28th.

Venus continues to shine brightly with about -4.2m, after Sunset. Easy target with naked eye or a binocular towards the South, after 5pm, but you need good views towards the South, as the bright planet’s altitude is only about 5 degrees above Horizon at that time, in the neighbourhood of Mars.

Mars is in Sagittarius, moving into Aquarius and setting early evening, after Venus.

Jupiter reappears, and well-located in the Eastern sky in Virgo before Sun-rise.

Saturn is not visible in December, because it is in conjunction with the Sun on the 10th.

Uranus is in Constellation Pisces, and is visible during the first part of the night. Uranus is about 37° high above the Horizon, when it is on the Meridian, therefore well-placed for observation with binoculars and telescopes.

Neptune is setting after Mars in Aquarius during December evenings. Visual magnitude is +7.8m. it may be possible finding it on the 6th of December nearby the Moon, if you have a telescope.


1. 2016 RASC Observer’s Handbook
2. Stellarium Software