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.
April 21, 2021: Evening Star is making its first appearance in the west-northwest shortly after sunset. The gibbous moon is near Leo, while Mars is near the foot of Castor.
April 21, 2021: Jupiter and Saturn are the bright morning planets in the southeast before sunrise. The stars are in front of the backdrop of Capricornus. The constellation looks like an oversized boomerang or stealth fighter.
April 20, 2021: Venus is very low in the west-northwest after sunset. The gibbous moon is in Cancer, between Regulus and Pollux. Mars, above the horns of Taurus, approaches the star cluster Messier 35.
April 20, 2021: Bright Jupiter and Saturn are in the southeastern sky before sunrise, gently moving eastward compared to the starry backdrop of Capricornus.
April 19, 2021: The first evening appearance of Venus for this apparition occurs this evening. Look for it low in the west-northwest about 20 minutes after sunset.