2024, September 3-7: Crescent Moon Joins Nightly Planet Parade

September 3-7, 2024:  After the New moon, the lunar crescent joins the nightly planet parade after sundown.  Each night through mid-month, Venus, Saturn, Jupiter, Mars, and Mercury parade westward.

Venus, Jupiter and the crescent Moon.
September 12, 2018: Venus, Jupiter and the crescent Moon.

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by Jeffrey L. Hunt

Nightly Planet Parade

Each night after sundown and before the next morning’s sunrise, five bright planets parade westward.  Venus and Saturn are visible during the early evening.  Jupiter and Mars rise around midnight, followed by Mercury near sunrise.

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Moon Joins Parade

Moon Joins Nightly Planet Parade
Chart Caption – 2024, September 4-7: At 30 minutes after sunset, the moon enters the evening sky, passing Venus, then Spica.

The moon joins the parade on the 4th after yesterday’s New moon phase, starting lunation 1258, the number of lunar cycles since the count began in 1923.  Tonight, the lunar orb sets only 25 minutes after nightfall.

Venus’ View Suffers from Shallow Angles

Venus from Galileo (NASA photo)
Photo Caption – Venus as viewed from the Galileo spacecraft (NASA photo)

We have a poor view of the solar system in the western sky after sundown at this season.  The plane of the solar system has a low angle with the horizon.  Venus’ visibility suffers from this geometry.

Venus’ slow appearance mimics the moon’s change from night to night.  The accompanying chart shows the low angle the moon makes with the horizon.  By September 7th, the moon is over 10° above the horizon, although it is nearly 60° east of the sun.  Nightly, it moves about 13° eastward, but gains only 10° in altitude – height above the horizon – by the end of the period in this planet forecast.

Nightly Highlights: September 4-7

Use a binocular to track the moon’s place at 30 minutes after sunset.  Here are the highlights:

Venus Migrates Southward
Chart Caption – 2024, August 4: During bright evening twilight, use a binocular to see Venus, Moon, and Spica.
  • September 4: Find Venus about 5° up in the west.  It shines through bright evening twilight.  The lunar crescent, 3% illuminated, is near the horizon and 4.3° to the planet’s lower right.
2024 2025 Venus Evening Star
Chart Caption – 2024, September 5: Venus, Moon, Spica are in the western sky at 30 minutes after sundown.
  • September 5: This evening the lunar crescent, 8% illuminated, is higher in the west-southwest and 7° to Venus’ left.  The crescent is about midway from Venus to Spica, 8.5° to the moon’s upper left, too far away to fit in the same binocular field. Begin looking for earthshine, sunlight reflected from Earth’s features that gently lights the lunar night.
Venus Migrates Southward
Chart Caption – 2024, August 6: At 30 minutes after sundown, the crescent moon is to Spica’s left. They fit into the same binocular field. Venus is to Spica’s lower right.
  • September 6: The lunar crescent, 13% illuminated, is less than 10° above the horizon, 3.3° to Spica’s left, and less than 20° to Venus’ upper left. The moon occults or eclipses Spica from western Africa.  The event occurs during the daytime in eastern Canada and eastern US.  From New York City, the occultation begins at 11:31 a.m. Eastern Time.  The moon uncovers the star at 12:37 p.m. The moon is visible during the daytime and a telescope is needed to see the event.
  • September 7: Over 10° above the southwest horizon, the lunar crescent, 20% illuminated, is over 15° to Spica’s upper left and nearly 30° from Venus.

Use the binocular to watch Venus approach and pass Spica.  They fit into the same binocular field on the 12th.  Their conjunction occurs five nights later.

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