December 13, 2025: Jupiter retrogrades in front of Gemini for its second conjunction with Pollux ahead of its January 10 opposition. Find Jupiter in the west before sunrise and east-northeast after sunset.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:10 a.m. CST; Sunset, 4:20 p.m. CST. Times are calculated by the US Naval Observatory’s MICA computer program. Check local sources for sunrise and sunset times.
Jupiter’s Second Conjunction with Pollux Ahead of Opposition
As Jupiter’s opposition approaches on January 10th, the Jovian Giant retrogrades in front of Gemini near Pollux, one of the Twins.
Retrograde motion occurs for the outer planets when Earth — revolving around the sun faster and along a closer orbital path — overtakes them. The line of sight from Earth to the planet normally shifts eastward compared to the distant star field. As our world overtakes an outer planet, the line of sight shifts westward and the planet seems to move backward compared to its usual course. After Earth passes between the planet and the sun (opposition), the line of sight shifts eastward again.
Depending on the background stars in the region where this occurs, the more distant world can pass a bright star or even another outer planet three times. This is known as a triple conjunction and is occurring with Pollux.
While Pollux is nearly 7° north of the ecliptic, it serves as a milepost between Elnath — one of Taurus’ horns — and Regulus. The moon passes nearby each month, and the bright planets pass by regularly as well.
The first Jupiter–Pollux conjunction occurred on October 10th when Jupiter was moving eastward.
Jupiter began to retrograde on November 11th, resulting in today’s second conjunction. Jupiter reaches opposition during retrograde that ends March 10, 2026.
The third conjunction occurs on May 28, 2026, as Venus overtakes the Jovian Giant. A pretty Venus–Jupiter conjunction follows on June 9th. Mercury is also in this region and the moon joins the scene during mid-June.
As Jupiter approaches opposition it is in the sky nearly all night. Tonight, it rises in the east-northeast about 2.5 hours after sunset. Ninety minutes later, find it in the east-northeast, 6.9° to Pollux’s lower right. Jupiter outshines all other stars in the sky tonight and is easily located.
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