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.
- 2023, December 26: Cold Moon, Venus, Jupiter, SaturnDecember 26, 2023: The Cold Moon is visible during the nighttime hours. Venus shines before sunrise while Jupiter and Saturn are visible after sundown.
- 2023, December 25: Telescope First Light, Bright PlanetsDecember 25, 2023: For sky watchers with new telescopes, here’s what to look at before dawn or after sunset.
- 2023, December 24: Morning Moon, Pleiades, Antares Heliacal RisingDecember 24, 2023: The moon appears near the Pleiades star cluster during the earlier morning hours. Antares is at its first morning appearance, known as the heliacal rising.
- 2023, December 23: Check out Planet Uranus, Pleiades near MoonDecember 23, 2023: Look for the planet Uranus and the Pleiades star cluster through a binocular during nighttime hours.
- 2023, December 22: Mercury at Inferior Conjunction, Bright Jupiter, Gibbous MoonDecember 22, 2023: Mercury is between Earth and Sun, known as inferior conjunction. Jupiter and the gibbous moon are celestial companions during nighttime hours.