December: get out your night goggles to watch some magnificent sky-walkers:
Jupiter, in the East, and Venus, in the West, are King and Queen of the night.
Mercury is hiding again, between Earth and Sun, for most of this month
Mars is becoming brighter and is more elevated above the horizon
Saturn rises low in the South-East before sunrise, elusive but visible
~ Meteors Showers, Geminid and Ursid ~ a Total Lunar Eclipse on December 10/11 ~
*MERCURY, in retro motion in Tropical Sagittarius since November 23, is changing from Evening to Morning Star, moving from the Western sky after sunset to the Eastern sky before dawn, after forming an Inferior Conjunction with the Sun on December 4.
Mercury will remain invisible until the end of December, re-emerging in the South-East after December 20. On December 22/23 it could be easier to spot him (-0.4 magnitude) because of his vicinity to the tiny Balsamic Moon (two days before New Moon) and also his alignment to the star Antares (alpha of Scorpio constellation).
VENUS: Venus is becoming brighter every day, also more available for observation because she will remain longer in the western sky after sunset. Her magnitude will be around -3.9 throughout the month.
Venus and the tiny Crescent Moon (two days past New Moon) will appear very close in the evening of December 27.
Venus will reach her maximum brightness at the end of April 2012 (-4.5 magnitude), her maximum elongation or longitudinal distance from the Sun expected at the end of March.
*MARS: it will be easier to spot Mars this month, rising in the East a bit earlier every day. The Red Planet is also becoming brighter, from +0.7 to +0.2 magnitude. mars will be already well above the Eastern horizon by month’s end. He will remain relatively close to the two major stars of Leo constellation, Denebola and Regulus.
On December 18 the last Quarter Moon will transit in the vicinity of Mars, in the East, from one am until sunrise. providing a bright clue to spot Mars.
The Giant Planet is rapidly moving North-West, setting earlier as December advances, between two and three am at the start of December and just after midnight by the end of the month.
Jupiter is transiting against the backdrop of Cetus (the Whale constellation). He will be caught up in the Sun’s glare in mid-May 2012.
On December 6 and 7 the Waxing Gibbous Moon will be visually close to Jupiter for good part of the night.
In early April 2012 Saturn will reach his maximum elongation (distance) from the Sun and so also its greatest brilliance (+0.2 magnitude). In the month of December Saturn will shine at +0.8 magnitude only.
Saturn will still be transiting near the the alpha star of Virgo, Spica, the ear of corn in the maiden’s hand. On December 21 the Waning Moon will be aligned to both Saturn and Spica, in the East before sunrise.
Other major astronomical events in December
A Total Lunar Eclipse in the Tropical Sign of Gemini is on the cards for the Full Moon of December 10/11 (depending where you are in the world).
This Eclipse will be visible in its totality in most regions of Russia, the whole of Asia, including South East Asia, in China, Japan, the two Koreas, Indonesia, Papua New Guinea and Australia. It will not be visible from South America or Antarctica, and only partially from Europe, Africa, Mexico, North America and parts of Canada.
Meteors Showers are expected this month too, the Geminid and the Ursid. The Southern Hemisphere will be ideal to watch the first one, while the second will be visible only for people North of the Equator.
The Geminid will reach its peak on December 13,14 and 15, but some of its meteors could be glimpsed between December 6 and 19. Unfortunately the big Waning Moon (Disseminating Phase, after the Full Moon on December 10) may conceal many of its shooting stars (up to 80/120 per hour! One of the best meteors showers of the year). The spectacle will be worth the effort of rising early though, especially if you live away from city lights.
The constellation of Gemini, from which this shower radiates, rises before midnight in mid-latitudes in the Southern Hemisphere, so there would be many hours of opportunity for observation. The shooting stars will appear to generate in the vicinity of Castor (with Pollux, one of the Twin stars of the constellation Gemini), situated just below the Moon for southern observers. These meteors actually originate from the Asteroid Phaeton, an unusual occurrence because most showers come instead from comets.
The Ursid meteors shower (visible only to Northern observers), will have the advantage of a darker sky, its peak occurring two days before New Moon, on December 22 and 23. The shower itself goes on from December 17 to 25. The Small Bear or Little Dipper constellation, the place from where this shower radiates, is a circumpolar constellation, meaning that it does not rise above the horizon sufficiently in southern latitudes. This shower has less meteors than the previous one, 20-15 per hour, occasionally more. It originates from a comet called 8P/Tuttle.
All the Sky Snapshots have been generated using Stellarium, a wonderful Planetarium freeware software.
Information for the Sky Events has been gathered from these web sites: