This Week in the Sky-January 1-7, 2023
January 1, 2023
Bright Moon near Uranus (evening)
On Sunday, January 1, the waxing gibbous moon will rise after mid-day and then linger into the night sky until well beyond midnight. For observers in the Americas, the moon will have just completed an occultation of the magnitude 5.7 planet Uranus. Once the sky darkens in the Eastern time Zone, look for Uranus shining less than a lunar diameter to the moon’s west, allowing the moon and the planet to share the field of view in binoculars and backyard telescopes. In more westerly time zones, Uranus will be 3-4 lunar diameters from the moon. Observers in the Canadian Maritimes and eastward across Greenland, Iceland, most of northern Europe, and most of northern and western Russia can observe the occultation starting around 21:00 UT.
January 2, 2023
Mare Imbrium's Golden Handle (all night)
On Monday night, January 2, the terminator on the waxing gibbous moon will fall just west of Sinus Iridum, the Bay of Rainbows. That semi-circular feature, 155 miles (249 km) in diameter, is a large impact crater that has been flooded by the same basalts that filled the much larger Mare Imbrium to its east – forming a rounded “handle” on the western edge of the mare. The “Golden Handle” effect is produced when low-angled sunlight brightens the prominent Montes Jura mountain range surrounding Sinus Iridum on the north and west. Sinus Iridum is almost craterless, but hosts a set of northeasterly-oriented wrinkle ridges that are revealed at this phase.
January 3, 2023
Gibbous Moon Passes Mars (all night)
In the eastern sky on Tuesday evening, January 3, the bright, waning gibbous moon will be shining near prominent, red-tinted Mars. In the Americas, the Moon will be positioned to the east of Mars – close enough for them to share the view in binoculars. The pair will cross the sky together and set in the northwest before dawn. In the interim, the moon will drift farther from Mars and the diurnal rotation of the sky will lift the moon higher than the red planet. Around 19:00 UT observers in most of southern and eastern Africa, Madagascar, and the Maldives can watch the moon occult Mars.
January 4, 2023
Quadrantids Meteor Shower Peak (before dawn)
Named for a now-defunct constellation called the Mural Quadrant, the annual Quadrantids meteor shower runs from December 26 to January 16. Quadrantids meteors always travel away from a radiant point in the northern sky beyond the tip of the Big Dipper’s handle. This shower commonly produces bright fireballs because it is produced by particles dropped by an asteroid designated 2003EH. The Quadrantids’ most intense period, when up to 50 to 100 meteors per hour can appear, lasts only about 6 hours. The peak will occur on Wednesday, January 4 at 3:00 UT, which converts to 10 p.m. Eastern Time on Tuesday evening – but the optimal time for viewing Quadrantids in the Americas will be from midnight to dawn on Wednesday, while the shower’s radiant will be climbing the northeastern sky. A bright gibbous moon will obscure the fainter meteors before it sets around 4:30 a.m. local time.
Earth at Perihelion
On Wednesday, January 4 at 16:00 UT or 11 a.m. EST and 8 a.m. PST, the Earth will reach perihelion, its minimum distance from the sun for the year. At that time Earth will be 91.403 million miles (or 147.099 million km) from our star. That’s 1.67% closer than our mean distance of 1.0 Astronomical Unit. As winter-chilled Northern Hemisphere dwellers will attest, daily temperatures on Earth are not controlled by our proximity to the sun, but by the number of hours of daylight we experience.
January 5, 2023
Full Moon in the Winter Football (all night)
On Thursday night, January 5 the nearly full moon will shine inside the Winter Football, also known as the Winter Hexagon and Winter Circle. The asterism is composed of the brightest stars in the constellations of Canis Major, Orion, Taurus, Auriga, Gemini, and Canis Minor – specifically Sirius, Rigel, Aldebaran, Capella, Castor & Pollux, and Procyon. After Sirius rises in mid evening, the huge pattern will straddle nearly 70 degrees of the southeastern sky. Hours later the asterism will stand upright in the south, with the Milky Way passing vertically through it. The hexagon is visible during evenings from mid-November to spring every year. The full moon will shine on its eastern rim on Friday night.
Dual Shadows Cross Jupiter
On Friday evening, January 6, observers with telescopes in southern and eastern Asia and south to western Australia can watch the small, round black shadows of two of Jupiter’s Galilean Moons as they slide across that planet’s disk at the same time. At 7:50 p.m. Indochina Time (00:50 UT), the large shadow of Ganymede will begin to cross Jupiter’s southern hemisphere, joining Io’s smaller shadow, which began its own passage across Jupiter’s equatorial zone at 7:22 p.m. ICT (00:22 UT). 102 minutes later, at 9:32 p.m. ICT (02:32 UT), Io’s shadow will leave the planet. Ganymede’s shadow will complete its own transit 10:20 p.m. ICT (03:20 UT). These times will vary by a few minutes depending on your location.
January 6, 2023
Full Wolf Moon
The January full moon, which always shines in or near the stars of Gemini or Cancer, will occur at 6:08 p.m. EST, 3:08 p.m. PST, or 23:08 UT on Friday, January 6. This one is known as the Wolf Moon, Old Moon, and Moon after Yule. The Indigenous Ojibwe people of the Great Lakes region call it Gichi-manidoo Giizis, the “Great Spirit Moon”, a time to honor the silence, and recognize one’s place within all of Great Mystery’s creatures. (You might recall that name from hearing or singing Henry Wadsworth Longfellow's The Song of Hiawatha.) The Cree of North America call the January full moon Opawahcikanasis, the “Frost Exploding Moon”, when trees crackle from the extreme cold temperatures. Full moons during the winter months climb as high in the sky as the summer noonday sun, and cast shadows in the same locations. Ray systems radiating from the more recent craters are prominent around the full moon.
January 7, 2023
Bright Moon Joins Gemini's Twins (all night)
In the eastern sky on Saturday evening, January 7, the bright, recently moon will shine 6.5 degrees to the southeast of the bright star Pollux in Gemini. The somewhat fainter star Castor will shine above them. As the trio crosses the sky during the night, the eastward orbital motion of the moon will carry it farther from Pollux. The diurnal rotation of the sky will drop Gemini’s stars to the moon’s lower right after midnight local time.
The information presented here is taken from my personal copy of Starry Night 8 Pro Plus, all rights belong to Starry Night Education/Simulation Curriculum.