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.
October 22. 2021: Speedy Mercury is low in the east before sunrise. It is putting on its best morning performance of the year. Arcturus, in the east-northeast, is about the same altitude as Mercury.
October 21-November 1, 2021: Brilliant Venus steps through Ophiuchus to the upper left of the star Antares in the southwest after sunset . Afterward, the planet steps farther eastward.
October 21, 2021: The bright moon is low in the west about an hour before sunrise. Mercury is in the east at about the same altitude as Arcturus. Venus, Saturn, and Jupiter shine from the evening sky.
December 18, 2021: This is the anticipated launch date of the James Webb Space Telescope, the largest and most sophisticated space telescope view the universe.
October 20, 2021: Mercury is brightening in the morning sky. Brilliant Venus, Jupiter, and Saturn are in the evening sky. The bright moon starts the evening low in the eastern sky.