Four planets are visible on October 15. Venus and Mars are in the morning sky. Mars returns to the sky during the early evening along with Jupiter and Saturn.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:04 a.m. CDT; Sunset, 6:08 p.m. CDT. Check local sources for sunrise and sunset times.
Morning: The old crescent moon is low in east about one hour before sunrise. Venus and Mars are morning planets. Venus is “that bright star” in the eastern sky before sunrise. Mars, now past opposition is very low in the west, setting a few minutes before sunrise.
The higher Venus is in the eastern sky, the lower Mars is in the western sky. They are approaching their opposition so that Venus rises as Mars sets. This occurs on November 9. After that date, the two planets are not in the sky at the same time until next summer when they appear in the evening sky together.
Detailed morning note: One hour before sunrise, Venus – about 24° up in the east-southeast – is 0.3° to the lower right of Chi Leonis (χ Leo). The moon (28.0 days after the New Moon, 3% illuminated) is about 7° up in the east, nearly 20° to the lower left of Venus. Through a telescope, Venus is 14.2” across and 76% illuminated, a morning gibbous phase. Mars – 144.2° of ecliptic longitude west of Venus – is over 9° up in the west. The Venus – Mars gap has grown over 20° since the month begins. Venus is quickly stepping eastward in Leo as Mars retrogrades in Pisces.
Evening: Mars, Jupiter, and Saturn are evening planets. Bright Jupiter is low in the south with Saturn to its upper left. The planets are slowly moving eastward compared to the stars from night-to-night. Farther east, bright Mars – distinctly a rusty tint – is low in the east during early evening. It is in the south at nearly 12:30 a.m. CDT tomorrow morning.
Detailed evening note:One hour after sunset, Mars is over 10° in altitude in the east. Jupiter – 91.3° of ecliptic longitude west of Mars – is over 25° in altitude in the south. Saturn is 6.4° to the upper left of the Jovian Giant. In the starfield, Jupiter is 3.1° to the lower left of Pi Sagittarii (π Sgr) and 1.3° to the lower right of 50 Sagittarii (50 Sgr). Saturn is 1.7° to the lower left of 56 Sagittarii (56 Sgr). An hour later, Mars is over 21° up in the east-southeast. It is 3.0° to the upper right of Mu Piscium (μ Psc), 1.6° to the upper left of 89 Piscium (89 Psc), and 2.6° to the lower right of Zeta Piscium (ζ Psc). Through a telescope, Mars is 22.2” across.
Read more about the planets during October.
November 3, 2021: Before sunrise speedy planet Mercury, the crescent moon, and the star Spica are grouped together. The trio does not appear this close together again until 2033.
October 31, 2021: There is no Halloween Full moon this year, and the phase is not close. The crescent moon is in the morning sky. Mercury is low in the east-southeast before sunrise. The planet pack – Venus, Saturn, and Jupiter – gleam in the evening sky.
October 29, 2021: Venus reaches its greatest elongation from the sun. It is in the evening sky with Jupiter and Saturn. The crescent moon and Mercury are in the eastern sky before sunrise.
October 29 – November 1, 2021: The crescent moon moves in front of the stars of Leo in the eastern sky before sunrise. Watch the moon appear lower and the phase shrink (wane) each morning. Also note that there is no Full moon on Halloween this year!
October 26, 27, and 28, 2021: During the early morning hours, the bright gibbous moon appears in front of Gemini’s stars.