2023, July 18: Three Evening Planets, Moon


July 18, 2023: After sunset, use a binocular to locate Venus, Mercury, Mars, and the crescent moon.  Before sunrise, it is easy to see Jupiter and Saturn.

Photo Caption – 2022, March 28: A close bunching of Venus, Saturn, Mars, and the crescent moon.


by Jeffrey L. Hunt

Chicago, Illinois:  Sunrise, 5:31 a.m. CDT; Sunset, 8:22 p.m. CDT.  Check local sources for sunrise and sunset times for your location.  Times are calculated by the U.S. Naval Observatory’s MICA computer program.

Summaries of Current Sky Events

Here is today’s planet forecast:

Morning Sky

Chart Caption – 2023, July 18: Jupiter is in the east-southeast during morning twilight.

Two bright morning planets, Jupiter and Saturn are easy to locate before sunrise.  The Jovian Giant is nearly 40° above the east-southeast horizon.  It is the brightest starlike body in the sky this morning and will remain at that ranking until Venus enters the sky during August.

Jupiter is slowly moving eastward in front of Aries, 11.8° below Hamal, the constellation’s brightest star.  Notice that the planet is about halfway from Hamal to Menkar, Cetus’ nostril.

Chart Caption – 2023, July 18: Saturn is retrograding in the west-southeast before daybreak.

Saturn, considerably dimmer than Jupiter, but bright at its own level, is over 35° above the west-southwest horizon.  The planet is slowly retrograding in front of Aquarius, 7.0° to the upper right of Skat, and 5.6° to the lower right of Lambda Aquarii (λ Aqr on the chart).  The stars are dim and a binocular may be needed to locate the starfield from urban and suburban settings.

Find the star Fomalhaut, about halfway from the horizon to Saturn.

Evening Sky

Chart Caption – 2023, July 18: Use a binocular to find Mercury and the crescent moon during bright evening twilight.

The moon is visible briefly in the western sky during bright evening twilight.  A binocular is needed to see the lunar crescent, 2% illuminated, 5.2° to the right of bright Mercury.  They easily fit into the same field of view.  At thirty minutes after nightfall, start with Mercury about 5° up in the west-northwest, then attempt to find the crescent to its right.  They set about thirty minutes later.

Chart Caption – 2023, July 18: Venus, Mercury, Mars, Moon, and Regulus are in the western sky after sundown.

When looking for Mercury and the moon, Venus is easily located to the upper left of the inner-most planet.  By forty-five minutes after the sun sets, Venus is only 5° above the horizon, over 14° to the upper left of Mercury, still above the horizon.

Venus sets three to four minutes earlier each evening compared to sunset.  This evening it sets less than two hours after the sun.

Mars, 7.8° to the upper left of the Evening Star, marches away from Venus and Regulus.  At this hour use a binocular to find the Red Planet and Regulus, 3.6° above Venus and 5.1° to the lower right of Mars.  The separation is too large for the three to fit into the same binocular field.  Either Mars and Regulus fit or Regulus and Venus.

The moon, Mercury, Venus, Regulus, and Mars span 25.2°.  Tomorrow evening the moon is higher in the sky.

Chart Caption – 2023, July 18: Saturn is in the east-southeast at three hours after nightfall.

Saturn, less than a month from its opposition with the sun that means Earth is between them, rises about two hours after sundown.  An hour later, it is nearly 10° above the east-southeast horizon.



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