April 6, 2021: This morning, the moon, Jupiter, and Saturn are low in the southeast before sunrise. The lunar crescent is 4.7° to the lower right of Saturn, while Jupiter is 12.5° to the lower left of the Ringed Wonder.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 6:25 a.m. CDT; Sunset, 7:22 p.m. CDT. Check local sources for sunrise and sunset times for your location.
If you are noting the sunrise time and sunset time, the length of daylight is nearing 13 hours. At Chicago’s latitude, this occurs tomorrow and daylight continues to rapidly grow through the month.
This morning the lunar crescent appears near Saturn. The crescent is less than 30% illuminated and appears 4.7° to the lower right of the Ringed Wonder.
A binocular reveals lunar features in high contrast along the terminator, the division between daylight and darkness where the sun is setting on the moon.
Use a binocular to note that Saturn is 2.3° to the upper right of Theta Capricorni (θ Cap on the chart).
Brighter Jupiter – 10° above the southeast horizon – is 12.5° to the lower left of Saturn and 1.9° to the upper left of Deneb Algiedi (δ Cap).
Tomorrow morning, the moon is near Jupiter.
A lunar day lasts the length of a lunar phase cycle, 29.5 days. The moon is in synchronous rotation so that it rotates at the same speed it revolves. The same side of the moon faces our planet. The lunar mountains, craters, and volcanic plains that make the “Man-in-the-Moon” shape are always visible from Earth, except at the New moon phase when the earth-facing side is in full darkness.
We do not see the far side of the moon. That far side receives nearly 15 earth-days of sunlight and darkness. This is the same for the side that faces Earth.
Detailed Note: One hour before sunrise, the moon (24.2d, 29%) is about 10° up in the southeast. Saturn is 4.7° to the upper left of the lunar slice. Bright Jupiter is 12.5° to the lower left of Saturn. In the starfield, Saturn is 2.3° to the upper right of θ Cap. Jupiter is 1.9° to the upper left of Deneb Algiedi. One hour after sunset, Mars (m = 1.4) is over halfway up in the west, 4.8° to the lower left of Elnath
Read more about the planets during April 2021.
October 8, 2021: The crescent moon approaches Venus in the western sky this evening, leading up to tomorrow’s close grouping of Venus, the crescent moon, and the three stars of the Scorpion’s head.
October 7, 2021: The lunar crescent returns to the evening sky for a short visit in the western sky after sunset. The bright planet pack – Venus, Jupiter, and Saturn – are visible during the early evening.
Mars is at its solar conjunction on October 7, 2021. It begins a slow return into the morning sky. By year’s end it appears low in the southeastern sky with the moon.
October 6, 2021: The moon is at its New moon phase today. This evening look for the three bright planets after sunset.
October 5, 2021: Before sunrise, a very thin moon is visible in the eastern sky. The evening planet pack – Evening Star Venus, Jupiter, and Saturn – are visible at the same time after sundown.