Planet Watch: January-March 2023

The nearest planet to the Sun is never very far out of our star's glow and so is often missed by observers. It begins the year as an evening object, setting soon after the Sun, and already difficult to see in the twilight. It passes between Earth and the Sun, reaching inferior conjunction on January 7, then enters the predawn sky, becoming visible at mid-month and reaching greatest western elongation on January 29, then retreating back into the Sun's glow by mid-February. It returns to the evening sky at the end of March.

The Moon can be seen near Mercury on the mornings of January 19 and 20 (easier on the 19th). They're close together again but very difficult to see in the Sun's glow on the morning of February 18. Their close encounter on March 21 is not visible in the Sun's glow.

The brightest of the planets is an "evening star" this season, visible shortly after sunset and dazzling! It has a couple of interesting encounters as it slowly passes from the stars of Capricornus the Sea-Goat into Aquarius the Water Carrier, then into Pisces the Fishes and finally Aries the Ram. On January 22, it passes a third of a degree from Saturn, and then a half-degree from Jupiter on March 1 (for comparison, a full Moon is a half-degree in apparent angular width). It then continues moving eastward against the stars, lingering in the evening sky after Saturn sets.

The crescent Moon makes its own set of close passes near Venus on the evenings of January 22 and 23 (difficult to see on the 22nd), February 21, and March 23 and 24.

The Red Planet is a prominent evening object all season, high in the east just after sunset in January. It moves slowly eastward along the northern horn of Taurus the Bull and by the beginning of February is very high in the east at nightfall. It gradually crosses into the Winter Hexagon in mid-February, and by the beginning of March is nearly overhead after dark. By the end of the season, it's high in the west just after sunset, about halfway on its journey across the Hexagon.

The Moon passes near Mars on the evenings of January 3, very close on January 30 (an occultation that will be seen from some areas is described in Highlights), February 27, and March 27 and 28.

The largest of the planets is an evening sight, shining brightly in the southwest just after sunset in January. A slow-moving planet, it remains against the stars of Pisces the Fishes all season, gradually descending toward the western horizon with the stars and becoming increasingly difficult to see in the glow of twilight by the end of March. At the end of February, watch as Venus approaches and passes a half-degree from it on March 1. On March 21-22, look low in the west after sunset for a beautiful pairing of Jupiter and the Moon, with Venus about 15 degrees above them.

The crescent Moon can be seen near Jupiter on the nights of January 25, February 22 (with Venus just below), and March 22 (very low in the west and difficult to see in the glow of sunset).

The Ringed Planet is an early evening object at the beginning of the season, located against the stars of Capricornus the Sea-Goat and (as noted above) passing less than a half-degree from Venus on January 22. It quickly sinks into the glow of sunset and is washed from view by the end of the month. Passing conjunction on February 16, Saturn reappears in the predawn sky in late-March, by which time it has moved into Aquarius the Water-Carrier.

The Moon passes near Saturn on the evening of January 22, when Saturn and Venus are very close together (the thin, day-old Moon may be too difficult to see in the twilight however). Their meeting on February 19 takes place well within the Sun's glare and is not visible, and their predawn encounter on the morning of March 19 will be a challenge to see, since the path of the planets is at a shallow angle with respect to the horizon, placing them very low in the sky at sunrise.

Times are for San Francisco, California, and will vary slightly for other locations.

January 1 (PST)
Sunrise | Solar Noon | Sunset
7:24 am | 12:13 pm | 5:01 pm 

February 1 (PST)
Sunrise | Solar Noon | Sunset
7:13 am | 12:23 pm | 5:33 pm

March 1 (PST) 
Sunrise | Solar Noon | Sunset
6:40 am | 12:21 pm | 6:03 pm