January begins with Orion rising sideways at dusk, and an exodus of naked-eye planets from the early evening sky—from four down to just Jupiter. The morning sky begins with one planet, faint Mars, and adds brilliant Venus in the second week. New moons on Jan. 2 and 31 make the moon’s cycle of phases neatly fit within the calendar month.
January’s evening sky: The year opens with a fine display of four bright planets spanning an arc of 38 degrees in the southwest sky at dusk. On Jan. 1, starting with the lowest and progressing to upper left, they are brilliant Venus, Mercury, Saturn and Jupiter. Choose a spot with unobstructed views toward the west-southwest horizon to catch the two planets interior to Earth’s orbit, because both, very low at dusk, will pass inferior conjunction—nearly between Earth and the sun—with Venus doing so on Jan. 8, and Mercury on Jan. 23.
Even if your view is blocked, you can still spot Venus, because it’s brighter than magnitude -4, and easy to find in the daytime using just a pair of binoculars. Protect your eyes! Be sure the sun is hidden before you search for Venus. On Jan. 1, when Venus sets within an hour after the sun, try for it in the late afternoon or at sunset, within 12 degrees to the upper left of the sun. Venus is now unusually close to Earth and backlighted by the sun, and shows a crescent shape easily resolved in binoculars. On Jan. 3, the crescent is only 1 percent illuminated. With each passing day, Venus appears closer to the sun, sets earlier and displays an even thinner crescent. On Jan. 4, Venus is within 8 degrees above the late afternoon sun and sets 38 minutes after it. If the sky is very clear on Jan. 8, by using binoculars or a telescope, you can try for the planet’s hyper-thin crescent within 5 degrees to the upper right of the sun.
Mercury begins the year at magnitude -0.7, quite bright, and fades slightly to magnitude -0.5 as it reaches its highest position, 5 degrees to the lower right of Saturn on Jan. 8. Four days later, on Jan. 12, Mercury, at magnitude 0.0, approaches within 3.4 degrees to the lower right of fainter Saturn at magnitude +0.7. The event is called a quasi-conjunction, because Mercury approaches Saturn, but won’t pass it until after retrograding and returning to overtake it, in the morning sky in early March.
Mercury fades to magnitude +1.0 by Jan. 15, and very quickly in following days. Saturn holds steady in brightness, but drops lower on its way to solar conjunction on Feb. 4. Before then, Saturn sets in mid-twilight on Jan. 24. Jupiter then becomes the only naked-eye evening planet, until it, too, disappears, in the third week of February. Uranus and Neptune can be picked up with binoculars, with the aid of good finder charts.
The eastern evening sky is filling with winter’s bright stars. In early January, you can still catch Orion low, as described in the opening lines of Robert Frost’s amusing poem, “The Star Splitter”:
You know Orion always comes up sideways.
Throwing a leg up over our fence of mountains,
And rising on his hands, he looks in on me …
Low in the eastern sky, 19 degrees apart, are Orion’s brightest stars, blue-white Rigel, his foot, and reddish Betelgeuse, his shoulder. Midway between them, look for three stars in a nearly vertical line, marking the Hunter’s belt. As the days pass, if you observe at the same stage of twilight each evening, Orion rises higher, making room below for his “Dog Stars” to appear: Procyon, the “before the Dog” star, rising a few degrees north of east; and Sirius, the “Dog Star” itself, rising in the east-southeast. Note the line of belt stars, extended downward, locates Sirius, the brightest star in the night sky.
Sirius, Procyon and Betelgeuse form the nearly equilateral Winter Triangle. If you look while Sirius is still very low, you can still see the entire Summer Triangle in the northwest to west. In order of brightness, its stars are Vega, Altair and Deneb.
In early January, Sirius rises in a dark sky. It will then flash vigorously, in many colors. From Southern California, catch Sirius and Altair at equal altitudes, a bit more than 4 degrees above opposite horizons. This occurs two hours after sunset on Jan. 2, at end of twilight on Jan. 9, and about one hour after sunset on Jan. 14 and 15. If mountains or buildings don’t block your view, you can see the Summer and Winter Triangles simultaneously.
January’s morning sky: In early January, before Venus emerges, the brightest points of light are golden orange Arcturus, high in the southeast to south; blue-white Vega, climbing in the east-northeast; and yellow Capella, low in the northwest. Capella, Castor, Pollux and Procyon form an arch sinking in the northwest to west. Spica is in the south to southwest, 33 degrees from Arcturus. Regulus is in the western sky, 37 degrees to the upper left of Pollux.
Altair rises just north of east before mid-month and competes the Summer Triangle with Vega and Deneb. Around Jan. 15 each year, the figure is equally visible at dawn and at dusk.
Antares is low in the southeast at dawn at the start of January each year. On Jan. 1, Mars is 5.6 degrees to the left of Antares. About 40 minutes before sunrise, look for the old crescent moon, 2 percent full, 12 degrees to the lower left of Mars and 15 degrees to the lower left of Antares. The moon is about 28 hours before new.
Imagine a competition between two red objects, Mars and Antares, to determine which is brighter. At the start of 2022, first-magnitude Antares beats Mars (magnitude +1.5) by about half a magnitude, but in December 2022, Mars, at opposition and making a close approach to Earth, will reach magnitude -1.8, outshining Sirius, the brightest star.
Mars in January moves eastward against the background of zodiacal stars by 0.7 degrees per day. By Jan. 9, Mars will be 10 degrees to the lower left of Antares; on Jan. 16, 15 degrees; and on Jan. 30 and 31, 25 degrees.
During the second week of January, Venus starts to be visible in the morning. On Jan. 8 and the days immediately following, use binoculars or a telescope to observe the emerging thin crescent Venus, again taking care to look only when the sun is completely hidden. On Jan. 8 Venus rises only 13 minutes before sunup, and the extremely thin crescent is within 5 degrees to the upper left of the hidden sun’s position. On Jan. 12, Venus rises 40 minutes before sunup, and the easier 1 percent crescent is 8 degrees directly above the rising sun. By Jan. 20, Venus rises nearly 1.5 hours before sunup, and the 5 percent crescent is 19 degrees to the upper right of the rising sun. On Jan. 26, Venus rises 1.9 hours before the sun, and displays a 10 percent crescent, 26 degrees to the upper right of the sun. On Jan. 31, Venus rises 2.2 hours before sunup, and displays a 15 percent crescent, 31 degrees to the upper right of the sun. Take advantage of the current opportunity to view Venus in its crescent phases; the next time Venus displays a crescent will be during the weeks leading up to and following the inferior conjunction of Aug. 13, 2023.
The moon in January: We’re in the midst of a period, lasting from mid-November 2021 through mid-May 2022, when all of the five bright planets appear within 90 degrees of the sun. Accordingly, all moon-bright planet conjunctions during those six months involve a crescent moon, which I think are visually the most appealing.
We’ve already described the old moon to the lower left of Mars on the morning of Jan. 1. Astronomical new moon, invisible, occurs on Jan. 2 at 10:33 a.m. Just 31 hours later, at dusk on Jan. 3, the young, 3 percent crescent moon will be 4 degrees up in southwest to west-southwest. Venus will then be setting 12 degrees farther to the right (look earlier to catch it). Mercury will be within 4 degrees to the upper right of the lunar crescent. Saturn will be 10 degrees to the upper left of Mercury, and finally, bright Jupiter will be 19 degrees upper left of Saturn.
For the next three evenings, Jan. 4-6, watch the waxing crescent moon ascend past the planets. On Jan. 4, Saturn is within 6 degrees to the right of the 8 percent moon and slightly lower. Mercury is within 13 degrees to the lower right of the moon. Jupiter is 16 degrees to the moon’s upper left.
On Jan. 6, the moon is at 24 percent. Jupiter is 13 degrees to its lower right.
The moon spends three nights in Taurus: On Jan. 12, the moon is 4 degrees to the south of the Pleiades star cluster, while Mercury pauses 3.4 degrees to the lower right of Saturn in a quasi-conjunction. On Jan. 13, the moon passes 6 degrees north of Aldebaran, eye of the Bull. On Jan. 14, the moon passes within 4 degrees south of Beta Tauri (Elnath, tip of the Bull’s northern horn).
On the evening of Jan. 16, the moon is 7 degrees from Pollux and Castor, the bright “Twin” stars of Gemini, and appears only 3-4 degrees south of Pollux the next morning. On Jan. 17, the full moon rises a few minutes before sunset and appears 7 degrees below Pollux as the sky darkens. On Jan. 18, the moon rises in twilight, only about 45 minutes after sunset.
After the full moon of Jan. 17, follow the waning moon each morning through Jan. 30. On Jan. 20, the gibbous moon (93%) is 4 degrees north of Regulus, heart of Leo, the Lion.
On Jan. 24, the 61 percent moon, one day before last quarter phase, is 5 degrees north of Spica, spike of grain in the hand of Virgo.
On Jan. 27, the 28 percent crescent moon is within 7 degrees to the upper right of Antares, heart of the Scorpion.
On Jan. 28, the 18 percent crescent moon is 9 degrees to the lower left of Antares. Find dim Mars 14 degrees to the moon’s lower left, and brilliant Venus 11 degrees to the left of Mars.
On Jan. 29, the moon is 10 percent illuminated and 3 degrees to the lower right of Mars. Venus is 10.4 degrees to the left of Mars.
On Jan. 30, the 4 percent crescent moon is 13.5 degrees below and slightly to the right of Venus. Mars is 10 degrees to right of Venus and slightly lower.
Illustrations of many of the events described above appear on the Abrams Planetarium Sky Calendar. To subscribe for $12 per year or to view a sample copy, visit www.abramsplanetarium.org/skycalendar.
Robert Victor originated the Abrams Planetarium’s monthly Sky Calendar in October 1968, and still produces issues occasionally. He enjoys being outdoors sharing the wonders of the night sky, and is hoping for the pandemic to end! Robert Miller, who provided the twilight charts, did graduate work in planetarium science and later astronomy and computer science at Michigan State University and remains active in research and public outreach in astronomy.