The Night Sky This Month: December 2022

Planet Mars
Image Credit: Lucas R

This year, the Winter Solstice occurs at 21:40 (UTC) on December 21st, when the Sun will be directly overhead the Tropic of Capricorn at latitude 23.440S. This solstice marks the start of winter in the northern hemisphere and the start of summer in the southern hemisphere.

December 8th brings Mars into opposition with Earth, meaning that on this day, Mars will be at its point of closest approach to Earth. While the planet will not be as close to Earth as it had been in the recent past, it will be close enough to observe some significant surface features with small to medium-sized telescopes.

The Moon Phases in December 2022

Full Moon
Third Quarter
New Moon
First Quarter
December 7th December 15th December 22nd December 29th

The Planets in December 2022

Mercury was recently at superior solar conjunction with the Sun, and the planet will therefore not be visible throughout December because it will reach its highest elevation during daylight hours.

Venus was like Mercury, also recently at superior conjunction with the Sun, and like Mercury, it will reach its highest elevation during daylight hours during the first half of December. Note, though, that by month’s end, Venus will rise to about 10 degrees above the southwestern horizon just after sunset.

Mars is now approaching a point of opposition and it will, therefore, be visible throughout the night during December. At the beginning of the month, Mars will become accessible in the northeast at an elevation of about 7 degrees, to rise to about 89 degrees just after midnight. By month’s end, Mars will become accessible at around 17:55 (EST) in the east, rising to an elevation of 88 degrees before setting in the northwest at about 4:17 (EST).

Jupiter is now visible as an early evening object, becoming accessible at about 17:44 (EST) at an elevation of about 50 degrees in the southeast, rising to an elevation of 62 degrees above the southern horizon. By month’s end, the King of the planets will become accessible at about 17:55 (EST), and rise to an elevation of 63 degrees above the southern horizon before setting at about 23:45 (EST).

Saturn is like Jupiter, an early evening object becoming visible in the south at about 17:59 (EST) at an elevation of about 46 degrees but note that since Saturn is now approaching the Sun, it will set progressively earlier as the month wears on. By month’s end, Saturn will set about 3 hours after sunset.

Meteor Showers in December 2022

December sees two meteor showers, these showers being:

The Geminids Meteor Shower is expected to peak after midnight on the night of 13th/14th December and it is widely regarded not only as a major shower but also as the King of meteor showers. Produced by the debris trail of an asteroid named 3200 Phaethon, the Geminids shower consistently produces 120 or more bright multi-colored meteors per hour during its peak period. While the waning gibbous moon will extinguish many of the fainter meteors this year, the Geminids are so numerous that most of the bright, fast-moving meteors are still expected to produce a spectacular peak.

The Ursids Meteor Shower is expected to peak on the night of 21st/22nd December but unlike the Geminids shower, the Ursids shower rarely produces more than about 10 or so meteors per hour during the peak period. However, this year, there will be no bright moonlight over the peak, so most Ursids meteors should be relatively bright when viewed from a dark site.

Although the radiants of these showers are in the constellations Gemini and Ursa Minor, respectively, meteors from both meteor showers can appear from almost any point in the sky.

Deep Sky Objects to Look for in December 2022

Messier 51 (Question Mark Galaxy, Rosse’s Galaxy, M51, M51a, NGC 5194, UGC 8493, PGC 47404, VV 001a, VV 403, Arp 85, GC 3572)

Located about 31 million light years away in the constellation Canes Venatici, M51 has the rare distinction that it was the first spiral galaxy to be classified as such. Being relatively bright with a magnitude of 8.4, this spectacular pair of interacting galaxies is an easy target for even modest binoculars. Still, medium-sized telescopes will resolve some of the structure of the major component of the pair, which is designated M51a.

M51a also hosts the first suspected extra-galactic planet- a planet located in a galaxy other than the Milky Way. Provisionally dubbed M51-ULS-1b, the candidate exoplanet appears to be slightly smaller than Saturn and orbits a high-mass X-ray binary system known as M51-ULS-1, which system appears to consist of either a neutron star or a black hole and a possible B-type supergiant star.

M94 (Messier 94, NGC 4736, UGC 7996, PGC 43495)

Also located in the constellation Canes Venatici, but at a distance of only about 16 million light years, this spectacular magnitude 7.9 spiral galaxy is an easy target for small to medium telescopes at low power.

While the double-ring structure of this galaxy has some scientific interest, M94 was the first galaxy that appeared to contain no, or very little dark matter– a theory that has since been disproved conclusively. Nonetheless, regardless of the amount of dark matter M94 contains, it is among the brightest members of the M94 Group, a small cluster of galaxies with between 16 and 12 galaxies. The M94 Group is only one of many similar clusters of galaxies that form the Virgo Super Cluster, which also contains the Local Super Cluster.

M101 (Messier 101, NGC 5457, UGC 8981, PGC 50063, Arp 26)

Located about 21 million light years away in the constellation Ursa Major, this magnitude 7.9 spiral galaxy is perhaps the most spectacular known example of a grand-design spiral galaxy. Containing about 1 trillion stars, M101 is about 50,000 light years wider than the Milky Way, which spans across “only” 100,000 to 120,000 light years.

It is interesting to note that Pierre Méchain, who discovered this galaxy, described it as “… [a] nebula without star[s], very obscure and pretty large, 6′ to 7′ in diameter, between the left hand of Bootes and the tail of the Great Bear. It is difficult to distinguish when one lifts the [grating] wires.”

Although M101 can be spotted with (modern) amateur equipment, to resolve some of the galaxy’s spiral structure requires telescopes larger than 12 inches, very dark skies, a low-power eyepiece, excellent seeing conditions, and some patience.

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