
Morning Star Venus and Mercury dance in front of the stars of Virgo before sunrise. Mars is visible in the east-southeast after sunset, while Jupiter and Saturn are in the south-southwest as a prelude to their Great Conjunction on December 21, 2020.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 6:27 a.m. CST; Sunset, 4:41 p.m. CST. Check local sources for sunrise and sunset times in your location.
International Space Station Pass (Chicago, Illinois area) begins at 5:12 a.m. CST low in the north-northwest. It reaches its highest point about 21° up in the north-northeast at 5:14 a.m. CST. It disappears at 5:17 a.m. CST about 10° up in the east-northeast. Find an unobstructed view to the north. The ISS moves near the star Arcturus low in the east-northeast before it disappears.
Morning: Venus and Mercury dance among the stars during early morning before sunrise. Venus is “that bright star” in the eastern sky before sunrise. Use a binocular to see the planet near Gamma Virginis (γ Vir on the chart). Look again tomorrow morning to see that Venus has passed the star. The planet rises after 3:30 a.m. CDT. This morning at this hour, the bright gibbous moon is visible in the west between the horns of Taurus as outline in yesterday’s article. Mars is less than 10° in altitude in the west and sets about 45 minutes later. In less than a week, the planets do not appear in the sky at the same time. As morning twilight progresses, look for the star Spica and Mercury low in the east-southeast. Mercury is 4.2° to the left of Spica, but both are low in the sky.
Morning detailed note: What is the last date that you see Mars and Venus in the sky simultaneously? At 4 a.m. CST, Mars is near the western horizon while brilliant Venus is low in the east. One hour before sunrise, Venus is about 20° up in the east-southeast. It is 1.8° to the upper right of Gamma Virginis (γ Vir) and 3.9° to the lower left of Eta Virginis 9η Vir). Farther west, the moon (18.7d, 87%) is still visible between the Horns of Taurus and near their points. The lunar orb is 2.4° to the right of Zeta Tauri (ζ Tau) and 5.5° to the left of Beta Tauri (β Tau). The Crab Nebula (M1, NGC 1952) is 1.3° to the lower left of the bright lunar orb and 1.1° to the right of ζ Tau. This is not the time to view the nebula, but note where it is compared to ζ Tau and the moon. Return when the moon is dimmer to view this supernova remnant. As the sky brightens further, find Mercury (m = 0.2) 4.2° to the left of Spica, nearly 7° up in the east-southeast.
See our summary about Venus during November 2020 and the feature article about Venus as a Morning Star.
Evening: Mars, Jupiter, and Saturn continue to shine as evening planets. Bright Mars is in the east-southeast among the stars of Pisces. Use a binocular to spot the planet near the stars Epsilon Piscium (ε Psc on the chart) and 80 Piscium (80 Psc). Jupiter and Saturn are in the south-southwest. Saturn is 4.8° to the upper left of Jupiter. The Jovian Giant is slowly inching eastward toward Saturn for their Great Conjunction. Look at Jupiter with a binocular to pick out up to four of its largest moons. They appear as bright stars on either side of the planet. Later this evening look for the moon low in the east-northeast. It is in front of the stars of Gemini.
Evening detailed note: One hour after sunset, Jupiter is nearly 24° up in the south-southwest. Saturn is 4.7° to the upper left of the Jovian Giant. In the starfield, Jupiter is 1.5° to the left of 50 Sagittarii (50 Sgr) and 4.0° to the lower right of 56 Sagittarii (56 Sgr), while Saturn is 2.1° to the lower left of the same star. Farther east, Mars is nearly 23° above the east-southeast horizon. It is retrograding in Pisces. This evening, it is 2.4° to the upper right of 80 Piscium (80 Psc) and 3.2° to the lower right of Epsilon Piscium (ε Psc). Five hours after sunset (9:45 p.m. CST), the moon (19.3 days after the New moon phase, 82% illuminated) – over 22° up in the east-northeast – is 1.5° to the upper left of Eta Geminorum (η Gem, m = 3.3). The open star cluster M35 (NGC 2168) is 1.5° above the moon. Like the Crab Nebula, return to this part of the sky with low power when the moon is dimmer.
For more about the Great Conjunction, read our feature article. This is the closest Jupiter – Saturn conjunction since 1623.
Read more about the planets during November.
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