Mars is at its solar conjunction on October 7, 2021. It begins a slow return into the morning sky. By year’s end it appears low in the southeastern sky with the moon.
By Jeffrey L. Hunt
The Red Planet is at its solar conjunction on October 7. The planet, sun, and Earth are in a line so that Mars is hidden in bright sunlight.
The planet begins a slow return into the morning sky. Compared to Venus, Jupiter, and Saturn that are visible in the evening sky during the fall and early winter of 2021, Mars is quite dim and nearly indistinct. At the end of the month, it rises about 40 minutes before sunrise. It is still dim and hiding in bright twilight.
By November 10, Mars rises nearly one hour before sunrise although it continues to be dim compared to what we expect for Mars’ brightness. Thirty minutes later, it is less than 5° above the east-southeast horizon. Bright Mercury is 1.0° to the upper left of the Red Planet. A binocular is needed to see the pair. This is pushing the limits of the planet’s visibility.
Nearly two weeks later, Mars passes 0.1° to the lower left of Zubenelgenubi, “the southern claw of the scorpion,” that is returning to the morning sky. Mars continues to be dimmer that what we might expect, although it is three times brighter than the star. Forty-five minutes before sunrise, the pair is less than 5° above the east-southeast horizon.
The moon is helpful to find Mars on December 2. Mars rises about 90 minutes before sunrise. Forty-five minutes before sunrise, the planet is nearly 7° up in the southeast. The crescent moon, 5% illuminated, is 6.6° to the upper right of the planet.
Mars, the lunar crescent, and Zubenelgenubi tightly fit into a binocular field. The star is 0.7° to the right of the moon.
Over two weeks later, Mars passes 1.0° to the lower right of Graffias, the second brightest star in Scorpius.
Mars continues eastward and passes its “rival,” Antares, on December 27. On this morning, it rises nearly two hours before sunrise. At 45 minutes before sunup, the Red Planet is over 10° up in the southeast. Antares is 4.5° to the lower right of the planet.
On New Year’s Eve morning, look for a crescent moon 4.0° to the upper right of Mars and 3.4° to the upper left of Antares. The trio easily fits into the same binocular field of view. Find Mars over 10° up in the southeast.
The Red Planet slowly returns to the morning sky during autumn and early winter of 2021. Find clear a clear horizon to the south-southeast and begin looking for it during November.
- 2023, December 21: Winter Solstice, Great Conjunction Plus 3 YearsDecember 21, 2023: Winter begins in the northern hemisphere. Jupiter and Saturn are visible in the evening sky three years after their Great Conjunction.
- 2023, December 20: Morning Star, Evening Moon Nears JupiterDecember 20, 2023: Brilliant Venus is in the southeast before daybreak. After nightfall the gibbous moon nears Jupiter in the southeast sky.
- 2023, December 19: A Scorpion Fumble, Moon MidwayDecember 19, 2023: Before sunrise, Venus appears below the Scorpion’s claws. After sundown, the moon is nearly midway from Saturn to Jupiter.
- 2023, December 18: Pinched VenusDecember 18, 2023: Look for Venus between the Scorpion’s claws in the southeast before sunrise. The thick crescent moon is in the evening sky with Jupiter and Saturn.
- 2023, December 17: Celestial PairsDecember 17, 2023: Before sunrise, Venus passes Zubenelgenubi, a planet-star conjunction. After sundown, Saturn and crescent moon are paired, a planet-moon conjunction.