In January, Venus dominates the evenings! Find it in the southwest to west-southwest, with Mars to its upper left. In the west to west-northwest, find the Summer Triangle of Vega, Altair and Deneb. Vega is its brightest member, and Altair is the first to depart, around mid-month, if mountains don’t block your view. Fomalhaut, to the lower left of the two planets, may be easily overlooked.
The eastern sky is filling up with winter’s jewels! The “Dog Star” blue-white Sirius (the brightest star) and the Little Dog Star Procyon, preceding it, rise into view below Orion’s bright shoulder, red Betelgeuse, and bright foot, blue Rigel. (Sirius, Procyon and Betelgeuse form the nearly equilateral Winter Triangle.) Follow Orion’s belt downward to Sirius, and upward to orange Aldebaran, eye of Taurus, the Bull. To the left of Orion, look for Pollux (with Castor, 4.5 degrees away). Midway between Orion’s belt and the North Star, look for bright, yellowish Capella, the Mother Goat star.
Meanwhile, Jupiter ranks first in brilliance in the dawn sky. Find it well up in the south to southwest, with Spica only 4 degrees away. High above them is golden Arcturus, brightest star of January mornings. Regulus sinks lower in the west-southwest to west as the month progresses. Still lower in the west to west-northwest, the last stars of the “Winter Hexagon”—Procyon, Pollux and Capella—make their exits. Low in the southeast morning twilight to the lower left of Saturn, Mercury brightens to magnitude 1 on Jan. 5, and to 0 on Jan. 11. These planets approach to within 7 degrees on Jan. 9, widening to 26 degrees by Jan. 31. Find red twinkling Antares to Saturn’s upper right. Blue-white Vega, ascending in the northeast to east-northeast, ranks next after Arcturus in brilliance. Altair emerges low in the east at midmonth, completing the Summer Triangle.
The first evening of the New Year, Sunday, Jan. 1, features a beautiful crescent moon a few degrees to the lower right of brilliant Venus. Notice dim reddish Mars starting this month within 12 degrees to the upper left of Venus. On the next evening, find a slightly thicker crescent moon between Venus and Mars, closer to Mars. In early January in the Coachella Valley, sunset still occurs before 5 p.m., so 6 p.m. is a great time to enjoy these moon-planet gatherings.
By Thursday evening, Jan. 5, the waxing moon has reached first quarter phase, 90 degrees (a quarter-circle) from the sun, and appears half-full. On Sunday night, Jan. 8-9, from dusk until moonset (after 3 a.m. on Monday), watch the gibbous moon gradually creep closer to Aldebaran. On Wednesday, Jan. 11, the moon rises about 20 minutes before sunset. Full late that night, the moon passes several degrees south of the stars Castor and Pollux in Gemini. Each year late in January’s second week, our planet Earth passes between the sun and the Twins, causing those stars to remain above the horizon all night.
By Thursday evening, Jan. 12, the moon has passed full and rises about 40 minutes after sunset. Taking time out to watch moonrises with those you love can be relaxing and fun! Here are times for Palm Springs: Thursday, Jan. 12, at 5:38 p.m.; Jan. 13 at 6:42 p.m.; and Jan. 14 at 7:45 p.m. From the Coachella Valley, with our mountain surroundings, it might take several extra minutes until the moon’s disk becomes visible.
To continue following the moon, shift your viewing time to mornings. Within three hours after sunset on Saturday evening, Jan. 14, the waning gibbous moon rises closely south (to the lower right) of Regulus. The moon remains near that star for the rest of the night, with the pair moving into the western sky at dawn.
Jupiter, of magnitude -2 and well up in the south to south-southwest an hour before sunrise, rules the dawn. Note first-magnitude Spica move from 4.4 degrees from Jupiter on Jan. 1, to 3.6 degrees on Jan. 31. The moon, approaching last quarter phase, is in a beautiful grouping with Jupiter and Spica from about midnight until dawn on the morning of Jan. 19. (The pair remains separated by about 4 degrees from January into March.) That same morning, about an hour before sunrise, around 5:50 a.m., we find Mercury reaching greatest elongation, 24 degrees from the sun. Look for bright Mercury low in the southeastern sky, 12 degrees to the lower left of Saturn.
A waning crescent moon appears widely north of Antares on the morning of Jan. 23, and more closely north of Saturn on the morning of Jan. 24. A thin old crescent moon appears near Mercury on moon’s last two mornings, Jan. 25 and 26.
Back to the evening sky: The new moon occurs on Friday, Jan. 27, at 4:07 p.m. Spot the first young moonabout 25 1/2 hours later, soon after sunset on the next evening. From the Coachella Valley, begin looking around 5:35 p.m., when the hairline 1 percent crescent will be six degrees up in the west-southwest, only 12 degrees from the sun, and 34 degrees to the lower right of Venus. Three nights later, on Jan. 31, the four-day-old waxing crescent forms a beautiful compact gathering with Venus and Mars. Can you fit all three within a single field of view of your binoculars?
This month, Venus attains spectacular brilliance, magnitude -4.4 to -4.7, in the southwest to west-southwestern evening sky, and on Jan. 11-12, reaches greatest elongation, 47 degrees east or to the upper left of the setting sun. Can you spot Venus with an unaided eye before sunset? On Jan. 1, telescopes reveal Venus 56 percent illuminated, nearly 0.4 arcminutes in diameter. Before mid-January, Venus wanes to only half-lit (50 percent), and on Jan. 31, Venus is a crescent, 40 percent lit, but grows to 0.5 arcminutes across. Then Venus will nearly double in apparent size by late March!
The Astronomical Society of the Desert will host the next in our series of monthly star parties on Saturday, Jan. 7, from 5-8 p.m. They are held at the Visitor Center of the Santa Rosa and San Jacinto Mountains National Monument, on Highway 74, within 4 miles south of Highway 111 in Palm Desert. Check www.astrorx.org for listings of our high-altitude star parties at Sawmill Trailhead starting at dusk. The next (at 4,000 feet—wear warm clothes!) will be held on Saturday, Jan. 21.
Also, check the link to our “Impromptu Star Parties,” which could be announced on short notice at any time. Coming events might include old and young crescent-moon watches at dawn and dusk; daytime and evening sessions to observe the crescent Venus; and sessions to observe flyovers of the International Space Station.
Whitewater Preserve will be hosting a star party on Saturday, Jan. 28, weather permitting, beginning at 6:30 p.m. Reservations are requested at 760-325-7222.
Robert C. Victor was a staff astronomer at Abrams Planetarium at Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs. Robert D. Miller 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.