December skies

- By James Edgar

November 19,2025

key points from this story:

• Full Moon is December 4
• Several lunar occultations occur
• Jupiter best viewed after sunset
• Geminid meteors peak December 14
• Winter solstice on December 21
• Venus and Mars not visible

The Moon presents a waxing gibbous phase as the month begins, with the full phase appearing on the 4th. Also on the 4th, the Moon drifts just north of the stars of the Pleiades (M45). The full Moon, at perigee of 356,963 km, generates high tides at coastal areas.

On the 7th, Jupiter is 4 degrees south of the waning Moon. One day later, the Moon is 1.4 degrees north of the Beehive Cluster (M44). The 10th sees Regulus 0.7 degrees south of our satellite; this is an occultation for most of Canada. Last quarter comes a day later, on the 11th.

On the 14th, Spica is 1.4 degrees north of the Moon. The 17th sees Luna at apogee of 406,322 km. The 18th has the Moon 0.4 degrees south of Antares; another occultation, but in the Southern Hemisphere. The Moon is new on the 19th.

For those seeking an observing challenge, Pluto is 0.6 degrees south of the Moon—an occultation in eastern Canada—on the 22nd. By the 27th, the two large planets Saturn and Neptune are 4 degrees and 9 degrees, respectively, south of the first-quarter Moon. Once again, the waxing gibbous Moon is 0.9 degrees north of the Pleiades.

Mercury appears in the eastern dawn sky for the best morning apparition of 2025 for Northern Hemisphere viewers.

Venus is too close to the Sun to be seen. Mars is too close to the Sun to be seen.

Jupiter rises in the east shortly after sunset, presenting a favourable opportunity for Northern Hemisphere viewing. The 7th sees the waning gibbous Moon 4 degrees north of the gas giant planet. A double shadow crosses the disk on the morning of the 24th.

Saturn is among the stars of Aquarius, slowly beginning prograde motion. The ring system opens up a little during the month, so we can see more of the south side. The first-quarter Moon glides by on the 27th.

Uranus is well placed for viewing all through the night. Neptune and Saturn are a pair in the western evening sky, but far enough apart that they’re in separate constellations—Pisces for Neptune and Aquarius for Saturn.

The Geminid Meteors peak on the morning of December 14. Winter solstice is on the morning of the 21st. The Ursid meteors peak on the morning of the 22nd.