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.
August 3, 2021: Four planets appear in the evening sky. Brilliant Evening Star Venus and dim Mars are in the west after sunset. A little later during the evening, Saturn and Jupiter are easily visible in the southeast.
August 2, 2021: Saturn is at opposition with the sun. Earth is between the sun and the planet.
August 1 – 6, 2021: The morning moon wanes toward its New moon phase in the eastern sky. It passes the bright stars that are prominent in the evening sky during the winter season in the northern hemisphere. The stars have been making their first appearances in the morning sky during summer. At this hour, Procyon and bright Sirius are the last stellar duo to appear.
August 6, 2021: In the northern hemisphere, summer’s midpoint occurs today at 6:27 p.m. CDT.
July 31, 2021: The slightly gibbous moon, nearing its Last Quarter phase, is in the southeast as morning twilight begins. It is near the planet Uranus, easily within reach of a binocular. Mira, a variable star, reaches its brightest next month.