December 12, 2022: Before sunrise, the gibbous moon is between Regulus and Pollux in front of Cancer. After sundown, the three bright outer planets – Mars, Jupiter, and Saturn – decorate the sky.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:09 a.m. CST; Sunset, 4:20 p.m. CST. Check local sources for sunrise and sunset times for your location.
Today’s sunset time is the earliest of the year. This continues through the 14th.
Jupiter’s Great Red Spot’s transit times, when it is in the center of the planet in the southern hemisphere: 3:40 UT, 13:36 UT, 23:32 UT. Convert the time to your time zone. In the US, subtract five hours for EST, six hours for CST, and so on. Use a telescope to see the spot. Times are from Sky & Telescope magazine.
This is the 50th anniversary of the last Apollo lunar mission – Apollo 17. December 12, 1972, was the mission’s fifth calendar day. On this day, Eugene Cernan and Harrison Schmitt made their second excursion on the lunar surface with the lunar rover. They completed another seven-hour exploration that covered nearly 2 miles. They collected over 30 pounds of lunar sample. At Shorty crater, they found orange soil, indicating lunar volcanism.
Summaries of Current Sky Events
Here is today’s planet forecast:
The bright gibbous moon, 84% illuminated, is over halfway up in the west-southwest before sunrise in front of Cancer’s dim stars. The lunar orb is about midway from Pollux to Regulus, Leo’s brightest star.
While the moon is bright, it appears near the Beehive star cluster, a bunch of stars in the plane of the Milky Way, like the Pleiades. The stellar bundle is 3.4° to the lower left of the gibbous moon. The scene is best viewed with a binocular. Once the cluster is located, move the binocular slightly so the moon is outside the field of view.
Sometimes the cluster is known as the Praesepe or manger. Two donkeys, Asellus Borealis and Asellus Australis, are nearby.
An hour before sunrise, Mars is less than 10° above the west-northwest horizon. It is 8.9° to the lower right of Elnath, Taurus’ northern horn. The Red Planet has been putting on a planetary show before sunrise, but the display is shifting toward the evening sky.
Venus and Mercury continue to emerge from bright the sun’s glare. For sky watchers wanting a challenging view. The two inner planets can be found low in the southwest about 20 minutes after sundown.
The Evening Star is less than 5° up in the southwest, about a binocular field north along the horizon or to the right of the southwest direction. Mercury is 5.5° to the upper left of Venus. Both fit into the same binocular field of view when Venus is placed to the lower right part of the field. Sky watchers farther southward see the planets higher in the sky at this time interval.
Venus and Mercury are slowly joining Mars, Jupiter, and Saturn for a five-planet display, including the moon, that begins on the 24th. From the sunset point looking eastward, the order is Venus, Mercury, Saturn, Jupiter, and Mars.
An hour after sundown, Jupiter is “that bright star” in the south-southeast. Planets look like stars to the unaided eye.
Jupiter is slowly moving eastward compared to the Pisces starry background. It is nearly 40° to the upper left of Saturn.
The Ringed Wonder, dimmer than Jupiter and Mars, is moving eastward compared to stars in eastern Capricornus. It is 1.9° to the upper right of Nashira. Watch Saturn slowly move closer to that star.
Mars, dimmer than Jupiter, is nearly 20° above the east-northeast horizon, 9.0° to the upper right of Elnath and the same distance to the upper left of Aldebaran, Taurus’ brightest star.
Spot the Pleiades star cluster. This morning the moon was near the Beehive cluster. Both are found in the plane of the galaxy, but the Pleiades are brighter and easily seen without a binocular.
The Red Planet continues to retrograde, even though opposition occurred five nights ago. Retrograde motion is a westward movement of the planet. It is an illusion that the planet backs up against the distance starfield. Mars is slower moving, so that when our planet moves between it and the sun, the line of sight shifts westward rather than its normal eastward direction. Retrograde continues for another month.
The best view of the three bright outer planets is about two hours after sundown, when Jupiter is about halfway up in the south. Mars is nearly one-third of the way up in the east, while Saturn is over 20° above the southwest horizon.
Mars is high in the south seven hours after sundown.
At 5:32 p.m. CST, Jupiter’s Great Red Spot is prominently placed in the planet’s southern hemisphere, near the middle of the globe. From Chicago, this is about ten minutes later than the scene described above. For sky watchers farther eastward, the planet is a little higher and in a darker sky. Use a telescope to see the planet’s cloud bands and the long-lived atmospheric disturbance.
By five hours after sundown, the gibbous moon, 79% illuminated, is about 10° above the east-northeast horizon, nearly 23° to the lower left of Pollux.
By tomorrow morning, the gibbous moon is in the western sky along with Mars, but the Red Planet is becoming more difficult to see.
- 2023, October 20: Jupiter’s Double Shadows, Mercury at Superior ConjunctionOctober 20: After midnight, Jupiter’s moons’ shadows dance across the cloud tops. Mercury is at superior conjunction.
- 2023, October 19: Poured Moon, See Planet UranusOctober 19: Sagittarius seems to pour the moon into the sky this evening. Find Uranus with a binocular.
- 2023, October 18: Moon-Antares Conjunction, Bright PlanetsOctober 18, 2023: The moon is near Antares after sunset. Venus, Jupiter, and Saturn are in the sky during the nighttime hours.
- 2023, October 17: Scorpion MoonOctober 17, 2023: The crescent moon is with Scorpius during evening twilight. Venus and Jupiter gleam from the predawn sky.
- 2023, October 16: Venus in Starry ConjunctionOctober 16, 2023: Venus passes a star in Leo before sunrise. A crescent moon is low in the western sky during evening twilight.