August 17, 2023: Jupiter and Saturn are visible during morning twilight. Jupiter’s Great Red Spot is visible through a telescope. Uranus can be spotted through a binocular.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 6:01 a.m. CDT; Sunset, 7:48 p.m. CDT. Check local sources for sunrise and sunset times. Times are calculated by the US Naval Observatory’s MICA computer program.
Summaries of Current Sky Events
SUMMARY FOR VENUS AS AN EVENING STAR
Here is today’s planet forecast:
An hour before sunrise, bright Jupiter is high in the southeast, slowly moving eastward in front of Aries, 13.2° to the lower left of Hamal, the constellation’s brightest star, and 11.3° to the upper left of Menkar, Cetus’ nostril.
Find the Pleiades star cluster to the left of the Jovian Giant, while Aldebaran and the Hyades star cluster are to the lower left.
Planet Uranus is in the region nearly between the Pleiades and Jupiter, 8.1° to the lower left of the Jovian Giant. While Jupiter is moving eastward, it begins to retrograde – appear to move westward compared to the starfield – on September 4th, stopping far short of the more distant planet. Uranus is too far away from Jupiter and the Pleiades to fit into the same binocular field of view with either of them.
To find Uranus, locate Jupiter through the binocular. Move the binocular slightly so that the Jovian Giant moves from the right side of the view. Four nondescript stars, Zeta Arietis (ζ Ari on the chart), Delta Arietis (δ Ari), Tau Arietis (τ Ari), and 63 Arietis (63 Ari) easily come into view. Adjust the binocular so that these field stars are near the top of the view. Dimmer Uranus, aquamarine in color, appears as a star near the center of the field of view. Through a telescope, a tiny globe is visible.
At 5:01 a.m. CDT through a telescope, Jupiter’s Great Red Spot is visible at the center of the planet in the southern hemisphere.
During morning twilight, Saturn – retrograding in front of Aquarius – is less than 20° above the southwest horizon and over 20° to the upper right of Fomalhaut that is less than 10° above the horizon.
Retrograde motion is an illusion from Earth approaching and passing between a more distant planet and the sun. The line of sight that extends from Earth through Saturn to the distant stars normally moves eastward against that starfield. As Earth approaches, the line of sight shifts westward, so that Saturn seems to back up.
With a binocular note that the Ringed Wonder is 7.9° to the right of Skat, the Aquarian’s knee, and 7.5° to the lower right of Lambda Aquarii (λ Aqr on the chart), together nearly forming an equilateral triangle.
Venus is racing into the morning sky. This morning it rises twelve minutes before the sun and it is above the eastern horizon at sunrise. It is not far enough east of the sun for easy observing. Look for it in five mornings.
Look for the crescent moon low in the western sky about 30 minutes after sundown. With a binocular find it to the right of the west cardinal point, about 5° above the horizon. The phase is only 2% illuminated with the lunar orb nearly 40 hours after the New moon phase.
Mercury is about 10° to the lower left of the moon, but it is too dim and too low in the sky to be seen. The planet is headed toward inferior conjunction and its best morning appearance of the year in the morning sky.
Mars is about 5° above Mercury, but it is a lost cause in this bright twilight. The Red Planet is quite dim and washed over by the afterglow of sunset.
Saturn is approaching opposition on the night of the 26th/27th as Earth passes between the Ringed Wonder and the sun. This evening the planet rises in the east-southeast twenty-five minutes after sundown. By two hours after sunset, Saturn is over 15° above the horizon.
Tomorrow morning during twilight, the planet appears again in the southwestern sky. Jupiter rises in the east less than three hours after Saturn. By tomorrow morning before daybreak, it is in the southeast.
- 2023, October 20: Jupiter’s Double Shadows, Mercury at Superior ConjunctionOctober 20: After midnight, Jupiter’s moons’ shadows dance across the cloud tops. Mercury is at superior conjunction.
- 2023, October 19: Poured Moon, See Planet UranusOctober 19: Sagittarius seems to pour the moon into the sky this evening. Find Uranus with a binocular.
- 2023, October 18: Moon-Antares Conjunction, Bright PlanetsOctober 18, 2023: The moon is near Antares after sunset. Venus, Jupiter, and Saturn are in the sky during the nighttime hours.
- 2023, October 17: Scorpion MoonOctober 17, 2023: The crescent moon is with Scorpius during evening twilight. Venus and Jupiter gleam from the predawn sky.
- 2023, October 16: Venus in Starry ConjunctionOctober 16, 2023: Venus passes a star in Leo before sunrise. A crescent moon is low in the western sky during evening twilight.