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2020, December 4: Morning Star Venus, Gibbous Moon, Evening Planet Dance

By Jeffrey L. Hunt on November 27, 2020 • ( 0 )

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2020, December 4: One hour before sunrise, the bright gibbous moon to the upper left of the Gemini Twins.

In the morning sky brilliant Morning Star Venus waltzes through Libra near Zubenelgenubi in the east-southeast. Venus is “that bright star” in the eastern sky before sunrise. The bright gibbous moon shines near the Gemini Twins in the western sky. In the evening sky, Mars – in the east-southeast – marches through Pisces. Jupiter closes the gap on Saturn as a prelude dance to the Great Conjunction, 17 evenings away.

by Jeffrey L. Hunt

Chicago, Illinois: Sunrise, 7:02 a.m. CST; Sunset, 4:20 p.m. CST. Check local sources for sunrise and sunset times in your location. Add the time intervals in the notes to your local sunrise or sunset times.

Morning: The bright gibbous moon is high in the west-southwest about an hour before sunrise. Its reflected sunlight easily casts shadows on the ground. Stand outside for a few moments and as your eyes adjust, you’ll see your own shadow from the moon as well as the shadows of your surroundings. Look carefully and you’ll see the Gemini Twins, Pollux and Castor, to the moon’s lower right. You may have to block out the moon’s glare. Simply use your hand as you would with the sun during a bright day. Farther east, brilliant Venus blazes from low in the east-southeast. It is 1.4° to the left of Zubenelgenubi. Use a binocular to see the planet 1.6° to the lower left of Mu Librae (μ Lib on the chart).

2020, December 4: One hour before sunrise, brilliant Venus is 12.0° up in the east-southeast, 1.4° to the left of Zubenelgenubi and 1.6° to the lower left of Mu Librae (μ Lib).

Venus is getting lower each day at this time interval. If you wait a little longer, Venus is higher in the sky. The stars will be more difficult to see. A binocular is necessary to see them as twilight proceeds.

2020, December 4: Brilliant Venus is 1.4° to the left of Zubenelgenubi.

Morning detailed note: One hour before sunrise, the moon (19.3d, 85%) is 49.0° above the west-southwest horizon. It is 6.7° to the upper left of Pollux. Farther east, brilliant Venus is 12.0° up in the east-southeast, 1.4° to the left of Zubenelgenubi and 1.6° to the lower left of μ Lib.

See our summary about Venus during December 2020 and the feature article about Venus as a Morning Star.

2020, December 4: One hour after sunset, Mars is over 41° up in the east-southeast, between ε Psc and 80 Psc. The Red Planet is 1.0° to the lower right of Epsilon Piscium (ε Psc) and 1.6° to the upper right of 80 Piscium (80 Psc.)

2020, December 4: Mars is in the southeast after sunset. It is entering a tiny triangle of dim stars make by Zeta Piscium (ζ Psc), Epsilon Piscium (ε Psc), and 80 Piscium (80 Psc).

Evening: In the evening, Mars continues marching eastward among the stars of Pisces. While dimmer than about two months ago when it was closest to Earth, it is the brightest “star” in the east. Use a binocular to notice that the planet is between Epsilon Piscium (ε Psc on the chart) and 80 Psc. When Zeta Piscium (ζ Psc) is added, the stars make a small nearly equilateral triangle. Make nightly observations to spot Mars changing its position in that triangle.

Read about Mars during December.

2020, December 4: One hour after sunset, Jupiter is 1.8° to the lower right of Saturn. Jupiter is 2.5° to the left of 56 Sagittarii (56 Sgr), while Saturn is 3.9° to the star’s upper left. Saturn is 4.2° to the lower right of Sigma Capricorni (σ Cap).

2020, December 4: One hour after sunset, Jupiter is 1.8° to the lower right of Saturn.

One hour after sunset, Jupiter and Saturn are low in the west-southwest. They are in eastern Sagittarius. Jupiter is overtaking Saturn as the Great Conjunction of December 21, 2020 approaches. Their separation this evening is 1.8° In the starfield a binocular is needed to watch the slow dance that the planets make with the stars and each other. This evening Jupiter is 2.5° to the left of 56 Sagittarii (56 Sgr on the chart). Jupiter is 2.5° to the left of 56 Sgr while Saturn is 3.9° to its upper left. Saturn is beginning to approach Sigma Capricorni (σ Cap).

Evening detailed note: One hour after sunset, Mars is over 41° up in the east-southeast, between ε Psc and 80 Psc. The Red Planet is 1.0° to the lower right of ε Psc and 1.6° to the upper right of 80 Psc. Farther west, Jupiter is over 18° above the southwest horizon. The Jupiter – Saturn gap is 1.8°. Dimmer Saturn is to bright Jupiter’s upper left. Great Conjunction Countdown: 17 days. Among the stars, Jupiter is 2.5° to the left of 56 Sgr, while Saturn is 3.9° to the star’s upper left. Additionally, Saturn is 4.2° to the lower right of σ Cap. Six hours after sunset (10:20 p.m. CST), the moon (20.0d, 79%) is over 19° in altitude in the east. It is in front of the dim stars of Cancer.

For more about the Great Conjunction, read our feature article. This is the closest Jupiter – Saturn conjunction since 1623.

Here is more about the planets during December 2020.

2021, February 19-21: Moon in Taurus

February 19-21: The bright moon moves through the constellation Taurus. Use a binocular to see the starry background with the moon.

2021, February 18: Evening Moon, Mars, Pleiades

February 18, 2021: The moon, waxing toward its First Quarter moon phase, is high in the southwest after sunset. Planet Mars is 3.8° to the upper right of the moon. Mars is parading eastward compared to the starry background in eastern Aries as it heads toward the Taurus border.