December 31, 2023: Hello, Mercury! The planet makes its first appearance in the morning sky. Several bright stars are appearing in the eastern sky after sundown.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:18 a.m. CST; Sunset, 4:29 p.m. CST. Check local sources for sunrise and sunset times. Times are calculated by the US Naval Observatory’s MICA computer program.
The parade of winter stars crosses the eastern evening horizon during the next month with several bright stars rising at sunset. From Earth’s revolution around the sun, the stars appear four minutes earlier each night. Six bright stars cross the horizon threshold and appear higher in the sky each evening as darkness descends. Here is the list of stars and the dates they rise in the eastern sky at nightfall.
| Star | Rises at Sunset date | Constellation |
| Castor | December 31 | Gemini |
| Betelgeuse | January 2 | Orion |
| Rigel | January 4 | Orion |
| Pollux | January 8 | Gemini |
| Procyon | January 24 | Canis Minor |
| Sirius | January 29 | Canis Major |
Summaries of Current Sky Events
Summary for Venus as a Morning Star, 2023-24
Here is today’s planet forecast:
Morning Sky
Brilliant Venus
An hour before sunrise, brilliant Venus is over 15° above the southeast horizon. It is approaching distant Graffias, 1.8° to the planet’s lower left. Venus steps into Scorpius and passes 0.9° to the upper left of the star tomorrow morning.
Venus is in front of the Scorpion for four mornings before quickly stepping in front of Ophiuchus.
The planet is over 10° to the upper right of Antares, the constellation’s brightest star, that marks the arachnid’s heart.
Venus is considerably lower in the sky each morning. Since the beginning of the month, the Morning Star has lost forty-five minutes of rising time compared to sunrise. This morning it rises two minutes short of three hours before sunrise.
Morning Gibbous Moon
Farther westward, the bright gibbous moon, 88% illuminated, is halfway up in the west-southwest, 2.9° above Regulus, Leo’s brightest star. Use a binocular to see Regulus and the Sickle of Leo, that outline the head of the Lion. The moonlight overwhelms the stars in the region.
Hello, Mercury!
At forty-five minutes before daybreak, make your first attempt to see Mercury. The speedy planet already has better visibility than the recent evening apparition. No bright star is in the region. Find a clear horizon looking toward the east-southeast and nearly 15° to the lower left of Antares. Mercury is dimmer than Antares, but brighter than the other celestial bodies in the region, except for Venus.
Mercury is higher each morning and continues to brighten. During mid-January, the planet is 11° to the lower left of Venus. So, Hello, Mercury!
Mars is slower entering the morning sky than Mercury. The Red Planet rises nearly 50 minutes before sunrise and it seems stuck in bright morning twilight.
Evening Sky
Bright Jupiter
Jupiter and Saturn are the two bright planets in the evening sky after sundown. Bright Jupiter resumes its eastward trek, after the illusion of retrograde ended yesterday. This evening, it is the brightest starlike body in the sky. Find it over halfway up in the southeastern sky at one hour after sundown.
The Jovian Giant is in front of Aries, 10.4° to the lower right of Hamal, the Ram’s brightest star, and 11.5° to the upper right of Menkar, the Sea Monster’s nostril.
Saturn
Saturn, considerably dimmer than Jupiter, but brighter than most stars in tonight’s sky, is about 30° up in the south-southwest, in front of Aquarius’ dim stars. It nearly makes an equilateral triangle with Skat, the Aquarian’s leg, and Lambda Aquarii (λ Aqr on the chart). Use a binocular to see the stars, especially in urban and suburban settings, but they do not appear in the same binocular field with the Ringed Wonder.
Saturn sets in the west-southwest over four hours after sundown. An hour earlier, Jupiter is in the southern sky.
Evening Moon
The moon rises about five hours after sundown. An hour later, it is nearly 15° above the eastern horizon, over 9° to the lower left of Regulus. The gibbous moon is in the southwest before sunrise tomorrow.