January 19-31: Planet Mars retrogrades past the Twins. Find Mars near Castor and Pollux in the east-northeast after sundown.

by Jeffrey L. Hunt
Events are described here relative to sunset. Find sunset times for the month in local media.
Mars Retrogrades Past the Twins

Bright Mars retrogrades in front of Gemini, near the Twins, Castor and Pollux. The planet’s nightly change is easy to observe, and during January 19-31st, the celestial trio tightly fits into the same binocular field.
Find distinctly reddish Mars in the east-northeast as the sky darkens. Now past opposition and the closest point to Earth, the Red Planet rises before sunset. It is about 20° above the horizon an hour after sundown.
Mars is the fourth brightest starlike body in the sky, after Venus, Jupiter, and Sirius, the night’s brightest star. Planet Venus easily outshines all the starlike bodies, and it is visible in the southwestern sky after nightfall.
Through a Binocular

The third and find conjunction after the illusion of retrograde ends on February 23rd. Mars passes Castor (3.8°) on March 13th, followed by the third conjunction with Pollux (4.0°) on March 31st.
Make observations each clear evening to watch Mars’ conspicuous westward movement compared to the Twins.
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