Night Sky Highlights for January-March 2023
By Jim Mazur
At the end of January, Mercury will make an appearance in the eastern sky just before dawn. It will be farthest from the Sun on January 30, but if you have a good view of the eastern horizon, it should be visible before sunrise for several days before or after this date.
Venus will start off January low in the west after sunset, getting higher in the evening sky as the winter progresses. At magnitude -3.9, it will be the brightest object in the sky. Its disk will be more than 80% illuminated, so through a telescope it will appear almost round. As noted below, during the winter months Venus will have a close conjunction with each of the four gas giants.
The red planet will be well placed for observing all winter as it drifts through Taurus. Its disk will be largest (about 15 arcseconds) at the beginning of the January and get progressively smaller through the winter as is moves farther from Earth. With the naked eye, its reddish hue should be interesting to compare with nearby red stars Aldebaran and Betelgeuse.
Jupiter is in Pisces, and at about magnitude -2 it is the second brightest planet in the evening sky, after Venus. It will be easy to observe through at least mid-March. After sunset on March 1, Jupiter will be less than 1 degree to the left of Venus. This conjunction of the two brightest planets should attract a lot of attention.
Located in eastern Capricornus, Saturn will be low in the southwest during the early evening in January. It will pass within about 0.4 degrees of Venus on January 22, providing a good opportunity for both visual observers and astrophotographers. By the beginning of February, Saturn gets lost in the evening twilight as it approaches the Sun.
With a simple finder chart (such as the in the link below), it is not too hard to find Uranus in the constellation Aries. It can be observed in the evening throughout the winter months. At about magnitude 5.8, it can be seen fairly easily in binoculars or a typical finderscope. Through a telescope, use at least 100x to see its small greenish disk. This planet’s turn at a close conjunction with Venus comes on March 30, when it will be slightly more than 1 degree to the south (left) of Venus.
Its close conjunction with Venus will offer telescope observers a good chance to find Neptune shortly after sunset on both February 14 and 15. With a finder chart, you can try to spot Neptune through a telescope throughout January and most of February, before it gets too close to the Sun to observe.
Finder chart for Neptune:
Deep Sky Objects
There are many great objects to observe during the winter months. Here are a few that are worth braving the cold to look for.
Open cluster in Canis Major
This wonderful group of stars is a good target for binoculars or telescope at low power. At magnitude 4.5, it can be seen with the naked eye on a clear dark night, just about 4 degrees below Sirius. The cluster is about 2300 light years away and has an angular size larger than that of the full Moon. Star-hop chart
Messier 42 and 43, the Orion Nebula
Diffuse nebula in Orion
Whether you look at this nebula with binoculars or a large scope, how much detail can you see? Even small scopes can show its lime green color, and larger scopes show pinkish areas as well. Small scopes will show the four stars of the Trapezium, and large scopes can reveal a few fainter stars in this grouping. Star-hop chart
Messier 46 and NGC 2438
Open cluster with planetary nebula in Puppis
This is a rich open cluster of about 150 stars, and as a bonus there is the small planetary nebula NGC 2438 (magnitude 11.5), which can be seen near the north edge of the cluster. NGC 2438 is probably not part of the cluster, but rather a foreground object. Star-hop chart
Open cluster in Puppis
Messier 47 is just over 1 degree to the west of Messier 46. The two clusters have very different appearances. Whereas the stars of M46 are fairly uniform in brightness, M47 features some very bright stars along with much dimmer ones. It is about 1600 light years away. Star-hop chart
Open cluster in Hydra
This is a fairly bright open cluster, about the size of the full Moon, containing about 80 stars. At magnitude 5.8, it is a good target for binoculars or any telescope at low power. It is about 2500 light years away. Star-hop chart
Messier 81 (Bode’s Galaxy) and 82 (Cigar Galaxy)
Galaxies in Ursa Major
This may the most popular pair of galaxies in the sky, and they can be seen in the same field of view with a wide-field eyepiece. At magnitudes 6.8 and 8.0, respectively, they can even be glimpsed in binoculars. After viewing them with low power, increase the magnification to see how much detail you can observe, especially in M82. These galaxies are about 12 million light years away. Star-hop chart
Messier 97, the Owl Nebula
Planetary nebula in Ursa Major
This is a fairly large faint oval, about 3 arcminutes in diameter but with low surface brightness so it can be easy to miss unless you look carefully. With a large scope, one or two of the dark “eyes” that give the nebula its nickname. The Owl is about 1700 light years away, about 1.7 light years in diameter. Star-hop chart
Spiral galaxy in Ursa Major
Just about 1 degree to the north-north-west of the Owl Nebula, look for this fuzzy oblong galaxy, a few arcminutes in length. It is easier to spot than the Owl Nebula because of its greater surface brightness. It is about 32 million light years away, almost three times as far as M81 and M82. Star-hop chart
NGC 2392, the Clown Face Nebula
Planetary nebula in Gemini
This is a bright planetary nebula that looks something like a face surrounded by a circular ruffy collar, hence its nickname. It has a high surface brightness and a distinct blue color that make it easy to spot in even small telescopes. Its central star of magnitude 10.5 is easy to see with a medium to large scope. Star-hop chart