December 25, 2020: The gap between bright Jupiter and Saturn widens each evening. Find them low in the southwest as night falls. Bright Mars is to the upper right of the gibbous moon. The Red Planet marches eastward in Pisces.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:17 a.m. CST; Sunset, 4:25 p.m. CST. Check local sources for sunrise and sunset times for your location.
As night falls, Jupiter and Saturn are low in the southwest. From about 45 minutes after sunset and for the next hour, they are high enough to be easily seen. Jupiter is the brighter and it is nearly an apparent full-moon diameter (0.4°) to the upper left of Saturn.
The gap between the planets widens each evening. Both are slowly moving eastward. Jupiter revolves around the sun in nearly 12 years, while Saturn’s orbital period is nearly 30 years.
Farther east the bright moon that is 85% illuminated is in the east-southeast. It is over 20° to the lower left of bright Mars.
The Red Planet is marching eastward among the dim stars of Pisces. Use a binocular to see the starfield with the bright moon in the sky. Mars is 4.7° to the upper left of Zeta Piscium (ζ Psc on the chart) and 2.6° to the lower right of dim Pi Piscium (π Psc).
Read about Mars during December.
Detailed note: One hour after sunset, Jupiter is over 10° above the southwest horizon, 0.4° to the upper left of Saturn. In the starfield, Jupiter is 1.8° to the lower right of σ Cap. Mars is 83.4° of ecliptic longitude east of Jupiter among the dim ζ Psc stars of Pisces. The Red Planet is marching eastward. It is 4.7° to the upper left of ζ Psc and 2.6° to the lower right of π Psc. The bright gibbous moon (11.3d, 85%) is over 24° to the lower left of Mars and about 14° to the lower right of Pleiades. Block the moon’s glare to see the star cluster.
Read more about the planets during December.
November 7, 2021: During the early evening Venus and the moon group together in the southwest.
November 6, 2021: The midpoint of Autumn occurs today.
November 3, 2021: Before sunrise speedy planet Mercury, the crescent moon, and the star Spica are grouped together. The trio does not appear this close together again until 2033.
October 31, 2021: There is no Halloween Full moon this year, and the phase is not close. The crescent moon is in the morning sky. Mercury is low in the east-southeast before sunrise. The planet pack – Venus, Saturn, and Jupiter – gleam in the evening sky.
October 29, 2021: Venus reaches its greatest elongation from the sun. It is in the evening sky with Jupiter and Saturn. The crescent moon and Mercury are in the eastern sky before sunrise.