April 13, 2021: The crescent moon returns to the western evening sky after sunset. Mars is now above the Bull’s horns in the west after sunset.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 6:13 a.m. CDT; Sunset, 7:30 p.m. CDT. Check local sources for sunrise and sunset times for your location.
Thirty minutes after sunset, the new moon, that is only 3% illuminated, is about 12° up in the west. Use a binocular to first locate the lunar crescent. As the sky darkens, it appears lower in the sky. The crescent sets at about 100 minutes after sunset.
By an hour after sunset, the moon is still nearly 7° up in the west-northwest and nearly 17° below the Pleiades star cluster. Use a binocular to see earthshine on the night portion of the moon and to spot a dozen or so stars in the star cluster.
At this hour Mars is about halfway up in the west, well-above the “V” of Taurus made by the Hyades star cluster and Aldebaran, and nearly 40° to the upper left of the lunar crescent. Mars is above a line from Elnath to Zeta Tauri (ζ Tau), the Bull’s horns.
The Red planet is 4.1° to the upper left of Elnath and 3.7° to the upper right of Zeta Tauri. It sets over 5 hours after sunset.
Here’s more about Mars during 2021.
Read about Mars during April.
Detailed Note: One hour before sunrise, Saturn is 16.0° up in the southeast. Jupiter continues to slowly move away from the Ringed Wonder. This morning the gap is 13.3°. The Jovian Giant is over 11° above the east-southeast horizon. Use a binocular during several mornings to estimate the speed of each planet compared to the starry background. The changes are small but noticeable when observed across several mornings. This morning Saturn is 1.8° to the upper right of θ Cap. Jupiter is 2.5° to the upper left of Deneb Algiedi and 0.5° to the upper right of μ Cap. Thirty minutes after sunset, the moon (1.9d, 3%) is nearly 12° up in the west. Thirty minutes later, it is less than 7° in altitude. At this time, Mars is less than halfway up in the west between the horns of Taurus. It is above a line from Elnath to ζ Tau. The planet is 4.1° to the upper left of Elnath and 3.7° to the upper right of ζ Tau.
Read more about the planets during April 2021.
April 25, 2021: Mercury passes Evening Star Venus this evening after sunset. Look low in the western sky about 20 minutes after sunset. Mars is marching eastward in Gemini, near the star cluster Messier 35. The bright moon is near Spica.
April 25, 2021: Morning planets Jupiter and Saturn are in the southeast before sunrise. Jupiter is in front of the stars of Aquarius, while Saturn’s starry background is Capricornus.
April 24, 2021: Brilliant Evening Star Venus and bright Mercury are entering the evening sky. They are low in the west-northwest during evening twilight. The bright moon is in the southeast in Virgo. Mars moves into Gemini as it approaches the star cluster Messier 35.
April 24, 2021: The bright gibbous moon is near a star in Virgo during the early morning. From parts of the Western Hemisphere, the moon covers the star. Before sunrise, bright morning planets, Jupiter and Saturn are in the southeast before sunrise.
April 23, 2021: Evening Star Venus and Mercury are entering the evening sky. They are found very low in the west-northwest after sunset. The bright moon is in the southeastern sky during the early evening. Mars is moving toward the star cluster Messier 35.