By Pat Beers Block
This month’s premier skylight performers include the very active Geminids (Class I, Major) and Ursids (Class I, Major) meteor showers. The Geminids shower promises to produce as many as 120 meteors per hour during much of December. The maximum meteor activity will occur on Dec. 13 and early morning on Dec. 14. The Ursids shower will be present throughout the last 2 weeks of December with the maximum activity date being Dec. 22 ( www.amsmeteors.org).
With the last Supermoon for 2024 present in November, the moon returns to its customary size and phase cycle. We can still enjoy the comforting cycle of the moon, from its new moon to 1st quarter, to full, to last quarter phases this month.
Other events this month include the escapades of the moon with various planets and stars, again ensuring that the moon is a key player in our celestial calendar. Additionally, there are a significant number of planetary, and planet/star conjunction alignments as well as the presence of the spectacular meteor showers that will captivate us as we gaze into the morning and evening sky to enjoy them.
Now that we have some insight into major events anticipated for December, let’s get ready to engage in observing these events by setting up your star gazing equipment, charging your cell phones and linking to Sky Guide, Sky View Lite, or any other star gazing applications that you find useful, and settling into your favorite viewing spot to witness the magic of the night and early morning skies!
Weeks 1 (December 1-7)
December 1 marks the beginning of this month’s new moon phase. This phase of the moon is a great time for stargazing since the bright side of the moon faces away from Earth and won’t overshadow celestial bodies and events. Of course, clouds and other weather patterns can always hinder sky viewing so try to be aware of weather predictions as you prepare for your stargazing experience.
On December 3, the planet Mars will be in conjunction (visually close to one another) with the Beehive Cluster (aka Messier 44) within the constellation Cancer.
On December 4, the moon will be in conjunction with the planet Venus. About 1 ½ hour after sunset, Venus will be visible by looking to the upper right portion of the area where the waxing (getting larger) moon rests.
On December 7, Jupiter will be in opposition (closest) to Earth with the Sun fully illuminating this planet throughout the night. Visibility of Jupiter’s four moons may be possible with binoculars; the cloud bands of Jupiter may be possible to view with a telescope.
Weeks 2 (December 8-14)
On December 8, the moon with be in conjunction with the planet Saturn. The moon also moves into the first quarter phase when the moon is illuminated on the right half.
On December 12, the moon moves into its perigee position, a spacial position where the moon is closest to Earth. The lunar perigee position produces the strongest tidal force on Earth’s tidal waters.
The moon will be in conjunction with the Pleiades (aka the 7 Sisters, and Messier 45) within the constellation Taurus on December 13. The Pleiades are part of an open star cluster; these stars were all born together about 100 million years ago and are located within a nebula (aka cosmic cloud).
The Geminids meteor shower will be at its peak the evening of December 13 through the morning of December 14. However, with the moon ascending to fullness, a good time to observe meteors will be on the morning of December 14 when the moon is low in the horizon and the brightness of the full moon is lessened.
On December 14, the moon will be in conjunction with the planet Jupiter. This visual illusion of physical closeness will appear in the constellation Taurus.
Week 3 (December 15-21)
A full moon appears on December 15. This full moon is known colloquially as the Cold moon. This is a Mohawk tribal name for the December moon based on the fact that the northern hemisphere typically experiences freezing cold weather this month. The moon will be positioned near the constellation Taurus. Provided the sky is devoid of clouds or precipitation, the evening sky will be delightfully illuminated with the entire face of the moon visible and smiling at us with its always friendly and inviting face.
The moon will be in conjunction with the star Pollux on December 17. The star Pollux can be found in the constellation Gemini.
On December 18, the moon will be in conjunction with Mars in the early morning sky, located near the constellation Cancer. The moon will also be in conjunction with the Beehive star cluster in the constellation Cancer in the evening sky.
On December 20, the moon will be in conjunction with the star Regulus, within the constellation Leo.
The winter solstice occurs on December 21 when the Earth tilts in such a way as to move the Northern hemisphere away from the Sun. This tilt away from the Sun results in shorten daylight hours in Fluvanna county.
Weeks 4 & 5 (December 22-31)
December 22 marks the maximum activity for the Ursids (Class I, Major) meteor shower during which up to 10 meteors per hour might appear. This shower emanates from constellation Ursa Minor ( the location of the Little Dipper). The optimum viewing time ranges from just after sunset until moonrise.
The moon moves into its last quarter phase on December 22. The moon will be illuminated on the left half of its surface.
The moon will be in occultation (crossing over another celestial body) with the star Spica within the constellation Virgo on December 24. This occultation makes it seem like the covered celestial body has disappeared from the sky.
On December 25, the planet Mercury will be positioned far enough from the Sun that Mercury will be visible in the eastern sky just before sunrise. This change in distance between the Sun and Mercury is known as the greatest elongation of Mercury. You may want to use your binoculars to enhance your viewing experience of this event.
On December 28, the moon will appear in front of (occultation) of the red star Antares located within the constellation Scorpius, producing a temporary “disappearance” of this star.
Finishing the month on December 30 is the completion of the lunar cycle with its return to the new moon phase.
So ends the celestial highlights that we can look forward to observing throughout the month of December. Also worth exploring throughout this and the new year are NASA’s asteroid detection events, space rocket and satellite launches, and sky shows like the aurora borealis that might appear in Fluvanna. With the perpetual motion of planets and stars, the daily changing sky promises to entertain you for a lifetime!
Until next month, keep your eyes facing the morning and evening sky to see the wonders of our universe as we Earthlings travel through it!
