Lineups of planets have often attracted attention for their supposed effects on human affairs—and for several days in early January, five solar system bodies are arranged in a nearly straight line in space, in the order Mars–Venus-sun-Earth-Jupiter.
But as seen from Earth, conditions for viewing Venus and Mars are now very poor, because those planets are in conjunction on the far side of the sun—Venus on Jan. 6, and Mars on Jan. 9—and lost in the solar glare for many weeks. (Mercury even gets into the act, passing beyond the sun just a bit later, on Jan. 21.) Since Venus’ progress around its orbit is faster than Earth’s, it will emerge into the western sky at dusk. By March 1, it will set an hour after the sun, and from April through July, it will set in a dark sky, after the end of twilight.
Mars’ orbital progress, like that of all the planets more distant from the sun, is slower than Earth’s. As a consequence, Mars will emerge into the eastern sky at dawn, but since Mars’ progress not much slower than Earth’s, and because of the unfavorably low position of the band of zodiac constellations in the morning sky, we won’t see Mars in a dark predawn sky until June.
For Jupiter, on the other hand, observing conditions during January are ideal. On the night of Jan. 9-10, Jupiter stands at opposition, 180° from the sun, and is above the horizon all night. Look for the brilliant planet shining at magnitude -2.7—brighter than any nighttime star—low in the east-northeast at dusk, highest in the south in the middle of the night, and low in the west-northwest at dawn.
All the other giant planets can also be observed at nightfall. Saturn is easy for unaided eye; at magnitude +1.1, it appears as the brightest “star” in the southwestern sky. Uranus, at magnitude 5.7, is easily seen in binoculars 5° south of the Pleiades cluster, and closely southwest of 13 and 14 Tauri, a pair of stars of magnitude 5.7 and 6.1, about one-third of a degree apart. Neptune, at magnitude 7.9, is a much greater challenge, but it’s just 3.4° to 1.7° from Saturn this month. Through binoculars, look for a 1° by 3° rectangle of stars in the same field to the left of Saturn. Its top two stars are near magnitude 5, with its lower two stars near magnitude 4.5. The four stars form the body or shell of Testudo, the Turtle, an obsolete constellation that deserves recognition, at least as an asterism. The Turtle’s neck and head are marked by two stars, 24 and 20 of Pisces, of magnitudes 5.9 and 5.5, respectively, extending in a straight line 2.8° long from 27 Piscium, at the upper right corner of the rectangle. The entire asterism of six stars, from 20 Psc to 33 Psc, spans just 5 1/4°, easily fitting into the field of view of most 7- or 8-power binoculars.
On Jan. 6, when Saturn passes closest to the south-southeast of 20 Psc, it is equidistant from 20 and 24 Psc, 0.9° from each. Also that night, find Neptune 3.2° to the northeast of Saturn and 1.6° north-northwest of 29 Psc.
The following event is worth viewing with binoculars or a telescope for several evenings before and after: On Jan. 18, as twilight ends, Saturn appears within 2’ (arcminutes) from the 5.9-magnitude star 24 Piscium, and closes the gap between them as the evening progresses. The star 24 Psc, marking the neck of the Turtle, is located 1.3° from 20 Psc and 1.5° from 27 Psc, on a line joining them. Saturn’s rings are gradually tipping more into view; they’re 1° from edgewise on Jan. 1, to 2.2° on Jan. 31, and 1.6° from edgewise on this night, when 24 Psc will appear close to the planet’s disk in the same high-power field. Titan, Saturn’s largest moon, is much fainter than the star and will appear east of the planet that same evening. Traveling in its 16-day orbit, Titan will appear farthest east of the planet on Jan. 21, and farthest west on Jan. 29.
It’s fun to follow the changing position of Jupiter against the background stars of Gemini as it retrogrades a total of 10° in four months, centered on its opposition of Jan. 9-10. During January alone, Jupiter shifts 4° westward. The change is easy to see with the unaided eye by noting the shape of the triangle Jupiter forms with the nearby “Twin” stars, Pollux and Castor. Also, watch for several evenings around Jan. 19, when Jupiter passes within 0.5° north of the 3.5-magnitude star Delta in Gemini.
Visit the Sky Calendar Extra Content Page at abramsplanetarium.org/msta, and you’ll find an account of the appearance of Saturn’s rings during its 29.5-year cycle; finder charts for Uranus and Neptune with a listing of events for early 2026; and an explanation of the twilight maps that accompany this column, with evening and morning maps for the rest of this year.
The Pleiades, or Seven Sisters star cluster, is one of the most enjoyable stellar sights through a pair of binoculars. In the same field, look for a pair of stars 21’ (0.35°) apart, within 5° south of the Pleiades. They are 13 and 14 Tauri, magnitudes 5.7 and 6.1. On Jan. 1, the 5.6-magnitude planet Uranus is closely southwest of the two stars. Uranus is still slowly retrograding, moving west and farther away from the pair, by less than a half-degree in all of January. In February, Uranus will resume direct (eastward) motion, and pass closely south of 13 and 14 Tauri during March.
Follow the moon at dawn: In the western sky on the mornings of Jan. 3 and 4, the full or nearly full moon appears near Jupiter, Pollux and Castor, and on Jan. 6, at 87 percent, near Regulus. On Jan. 10, a last quarter moon, half full, appears to the right of Spica, and the next morning, a 41 percent fat crescent appears to Spica’s lower left. On Jan. 14, a 16 percent moon appears close to the upper right of Antares. It should be easy to follow the waning crescent for two additional mornings as it moves sunward, and farther to the lower left of Antares. Look for earthshine on the moon’s dark side, where the moon is not illuminated by direct sunlight.
Besides the bright zodiacal markers the moon encounters during its two weeks in the morning sky, look for Capella, sinking in the northwest to lower right of Jupiter-Pollux-Castor; and Procyon, sinking low in the west, to the lower left of Jupiter. Watch the eastern morning sky for the emergence of Altair, to the lower right of Vega and Deneb, completing the Summer Triangle with them.
Follow the moon at dusk: On the evening of Jan. 2, look for bright Jupiter and the “Twin” stars Pollux and Castor to the lower left of the full moon. The moon rises later each night, and you can shift your lunar viewing times to the morning, until the moon returns to the evening sky on Jan. 19. About 30-40 minutes after sunset, from a viewing spot with little obstruction toward the west-southwest, try for the slender 2 percent crescent, 44° to the lower right of Saturn. With the zodiacal band steeply inclined to the horizon, the waxing crescent climbs rapidly up the western sky from one night to the next. On Jan. 22, the 18 percent moon is within 6° to the lower right of Saturn; on the next evening, it’s at 27 percent, and nearly 10° above Saturn. On Jan. 25, the first quarter moon, half full and 90° from the sun, is just below the compact obtuse triangle of Alpha, Beta and Gamma in Aries, of magnitudes 2, 3 and 4. On Jan. 27, the 71 percent moon is only 3° from the Pleiades. (Use binoculars.)
A line joining Jupiter and Saturn extended toward both horizons pretty well marks the position of the ecliptic, or plane of Earth’s orbit. The sun, moon and planets are always found within 9° of this line, and usually much closer, within a belt of constellations called the zodiac. In January’s early evening sky, the bright stars north of this belt include the Summer Triangle of Vega, Deneb and Altair, in west to west-northwest at dusk early in the month; and Capella, in the northeastern sky, north of the horns of Taurus, the Bull. Bright stars south of the zodiac at dusk include Fomalhaut, the bright star roughly below Saturn; Betelgeuse and Rigel, the two bright stars flanking the 3-star belt of Orion, the Hunter; and Sirius and Procyon, the two dog stars following Orion across the sky and forming the equilateral Winter Triangle with Betelgeuse, his shoulder.
On Jan. 1, Sirius, the brightest star, passes its highest point, directly south, at 11:58 p.m. in Reno. The star passes due south nearly 4 minutes earlier each night, and on Jan. 31 reaches its high point in the south at 10 p.m. in Reno. On any night in January, follow the constellation of Canis Major, the Greater Dog, across the sky from three hours before Sirius’ southern passage until three hours after, and consider Robert Frost’s poem (this link includes a map of the constellation): mistero.tripod.com/essays/canismajor.html
Robert Victor originated the Abrams Planetarium monthly Sky Calendar in October 1968 and still helps produce an occasional issue. He enjoys being outdoors sharing the beauty of the night sky and other wonders of nature. Robert Miller, who provided the evening and morning 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.
