October 19, 2021: Four bright planets are visible during a twenty-four-hour interval. Mercury is in the morning sky, while Venus, Saturn and Jupiter are joined by a nearly full moon.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:08 a.m. CDT; Sunset, 6:03 p.m. CDT. Check local sources for sunrise and sunset times for your location.
Mercury is starting its best morning appearance of the year. Forty-five minutes before sunrise, the speedy planet is over 6° above the eastern horizon. Each morning the planet is low in the sky, but brighter. Find a skyline free from buildings, trees, and other obstructions.
The star Arcturus is about 30° to the left of Mercury. The topaz star is making its first morning appearance before sunrise.
After sunset the bright moon is in the eastern sky. The lunar orb is at its official Full moon phase tomorrow morning after moonset in North America. Bright Jupiter and Saturn are low in the south-southeast to the upper right of the moon.
Both planets are moving eastward in front of the stars of Capricornus. Yesterday, Jupiter resumed its eastward motion compared to the background stars.
At forty-five minutes after sunset. brilliant Venus – over 10° up in the southwest – is stepping eastward in front of the stars of Scorpius. In two evenings, it moves into Ophiuchus.
This evening, look for Venus 3.6° to the upper left of Antares – the rival of Mars – and 3.3° above Tau Scorpii (τ Sco on the chart). Each evening, notice the growing gap between the planet and Antares.
Detailed Daily Note: Forty-five minutes before sunrise, Mercury (m = 0.1) is over 6° above the eastern horizon. During the next several mornings, the planet is higher in the sky and brighter each morning. In the evening, forty-five minutes after sunset, brilliant Venus is over 10° above the southwest horizon, 3.6° to the upper left of Antares and 3.3° above τ Sco. Saturn, moving eastward in Capricornus, is 28.0° up in the south-southeast. Bright Jupiter is 15.3° to the east (left) of the Ringed Wonder. Jupiter is slowing moving eastward. Its retrograde ended yesterday. The bright moon (13.5d, 100%) is 8° above the eastern horizon. Two hours after sunset, the moon is nearly 22° up in the east-southeast. The Jovian-planet duo is in the south. Bright Jupiter is nearly 33° up, but east of the meridian. Saturn is to the Jovian Giant’s lower right and noticeably west of the meridian. Use a binocular to see the giant planets in front of their starfields. Saturn is 1.4° to the lower right of υ Cap, while Jupiter is 3.8° to the lower right of μ Cap, 2.1° to the upper right of Deneb Algedi, and 1.4° above Nashira.
October 26, 2021: Mercury is at its greatest morning appearance for the year. Look low in the east-southeast before sunrise.
October 25, 2021: This morning the bright gibbous moon seems to be caught between the horns of Taurus. Mercury is making its best morning appearance. The planet pack – Venus, Jupiter, and Saturn are in the evening sky.
October 24, 2021: Saturn is at its closest to Jupiter as the Jovian Giant picks up eastward speed. The morning moon and Mercury are visible before sunrise. Brilliant Evening Star Venus, Saturn, and Jupiter are in the sky after sunset.
October 23, 2021: This morning the bright moon is near the Pleiades star cluster. Mercury is making its best morning appearance. In the evening sky, Venus, Jupiter and Saturn are easy to spot.
October 22. 2021: Speedy Mercury is low in the east before sunrise. It is putting on its best morning performance of the year. Arcturus, in the east-northeast, is about the same altitude as Mercury.