September 12, 2026: Before sunrise, Mars passes Castor in a wide conjunction while continuing its eastward march in front of Gemini. Jupiter shines lower in the eastern sky as Mars slowly closes the gap for their November conjunction.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 6:28 a.m. CDT; Sunset, 7:05 p.m. CDT. Times are calculated by the US Naval Observatory’s MICA computer program. Check local sources for sunrise and sunset times.
Venus as an Evening Star
Eastern Morning Sky
Mars passes Castor, one of the Twins, before sunrise in a wide conjunction.
Step outside an hour before sunrise and look eastward. The sky is full of stars. Sirius, the night’s brightest star, is about 20° above the southeast horizon, while bright Jupiter – noticeably brighter than the Dog Star – is about the same altitude above the east horizon. The Jovian Giant slowly rambles eastward in front of Cancer.
Mars-Castor Conjunction
This morning, Mars is 9.4° to Castor’s lower right and 6.7° to Pollux’s right. The Red Planet is nearly halfway from the east horizon to overhead and over 25° to Jupiter’s upper right.
Mars’ most recent conjunction with Castor occurred March 21, 2025. The next one occurs August 21, 2028, while Venus is in the vicinity.
Mars is about the same brightness as Pollux, likely not as bright as might be expected. The planet’s brightness varies greatly. At times it can outshine Jupiter when it is closest to Earth. This morning, the planet is over 165 million miles away and brightening as Earth overtakes it.
Castor and Pollux represent the Twins. They are 4.5° apart. Pollux is over 6° above the ecliptic – the plane of the solar system – while Castor is over 10° above the plane. They are celestial mileposts. The moon passes closely to Pollux on regular intervals, but the lunar orb never occults or eclipses the star.
Mars continues its eastward march, passing Pollux in five mornings. The planet slowly overtakes Jupiter, passing the Jovian Giant on November 16.
Watch Mars continue its eastward march as it passes Gemini’s brightest stars and slowly overtakes Jupiter.
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