During the next week Jupiter approaches and passes Saturn for their once-in-a-generation Great Conjunction on December 21, 2020.
On December 15, the razor-thin appears to the lower right of Jupiter and Saturn after sunset. The planets are 0.6° apart.
A little later as the sky darkens further and the moon sets, the planets are visible together low in the southwest.
Just 5 days before the conjunction the crescent moon shines beneath the converging planets. The planet gap is 0.5°, the apparent diameter of the moon in the sky. For the next several evenings, your pinky finger at arms length covers both planets.
December 17, the crescent moon appears to the upper left of the converging planets. The planets are 0.4° apart.
The moon is to the upper left of the planets. The gap between Jupiter and Saturn is 0.3°.
The waxing gibbous moon is to the upper left of the impending conjunction. Bright Jupiter is 0.2° to the lower right of Saturn.
One night before the conjunction, Jupiter is below Saturn.
Jupiter passes Saturn during daylight hours in North America and South America when they share the same celestial longitude – the definition of a conjunction. By nightfall the planets are still close in the southwest after sunset.
Conjunction evening! Jupiter is immediately to the lower left of Saturn.
Through a small telescope or spotting scope, both planets appear in the same field of view. Jupiter’s four largest moons and Saturn’s moons are easy to see.
A binocular may reveal some of the Jovian moons.
The planets are visible as separate “stars” to the unaided eye. They do not merge into a single point or suddenly brighten.
During the next week, watch the Jupiter move away from Saturn.
- 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.