What’s up in the December 2020 night sky? Get ready for the Great Conjunction! This historic merging of Jupiter and Saturn is not to be missed. Plus, find more skywatching highlights, including the very active Geminid meteor shower, the winter solstice, and the full Cold Moon.
Sky Watch December 2020
by Bob Berman, as featured in The Old Farmer’s Almanac
The Bright Planets
- As soon as darkness falls, look for Jupiter low in the southwest sky (in the direction of the sunset). You can’t miss Jupiter as it’s the brightest object in the night sky after the Moon.
- Using Jupiter as a pointer, look immediately to the King Planet’s east for Saturn. The Ringed Planet shines as bright as a 1st-magnitude star but it will seem dim compared to Jupiter.
- Mars also shines fiery-red in the night sky—but in the southeastern sky as darkness falls. It will lord over the night sky until well past midnight. On December 23, use the Moon to spot Mars which appears to shine right above the Moon.
- Venus, the brightest planet, is in the east before sunrise. In mid-December (11th through 13th), the crescent Moon appears to pass by Venus.
- Mercury is not visible to the naked eye this month but will return in January 2021.
The Great Conjunction of 2020
Get ready for the best conjunction of your lives. Historically called “The Great Conjuntion,” this once-in-20-years meeting between our solar system’s two biggest worlds, Jupiter and Saturn, will take place on the winter solstice, December 21, 2020!
So close are the two planets that they merge almost into a single “star,” near enough to fit together in the same telescope field of view and very much visible with the naked eye. At their closest, they’ll be only 0.1 degrees apart.
- Over the first three weeks of December, watch each evening as the two planets get closer in the sky than they’ve appeared in two decades.
- The young crescent Moon is near the two giant worlds of Jupiter and Saturn on the 16th and 17th. Look for them low in the southwest in the hour after sunset.
- Then Jupiter passes extremely close to Saturn from the 20th to the 22nd, coming closest on the 21st—the solstice.
On December 21, the two giant planets will appear just a tenth of a degree apart – that’s about the thickness of a dime held at arm’s length! This means the two planets and their moons will be visible in the same field of view through binoculars or a small telescope. In fact, Saturn will appear as close to Jupiter as some of Jupiter’s moons.
Look for them 45 minutes after local sunset, low in fading evening twilight, roughly 14 degrees above the southwestern horizon. Often too close to the Sun to be observable (as in 2000), this conjunction is truly great and not to be missed!
Bask in the Geminid Meteor Shower – December 13
Often the most active meteor shower of the year, the Geminids occur annually in early to mid-December. This year, they will peak on the night of December 13-14 (Sunday night till dawn Monday).
On a dark night, free of moonlight, you can easily spot 50 or more meteors per hour. On an optimum night for the Geminids, it may even be possible to see up 100 meteors per hour.
This year should be a spectacular show since the new Moon is on the 14th, meaning very dark skies for gorgeous viewing of the shooting stars!
Prepare for the First Day of Winter (The Winter Solstice)
Winter begins with the solstice on December 21 at 5:02 A.M. The winter solstice marks the beginning of the astronomical season of winter in the Northern Hemisphere and is the day with the fewest hours of daylight in the entire year. Read more about the winter solstice.
Bundle Up for The Full Cold Moon
December’s full Moon rises in the evening of December 29, 10:30 P.M. As a herald of the winter season and its frigid weather, this full Moon has traditionally been called the Full Cold Moon. Learn more about the Full Cold Moon.
Go to the Almanac rise/set calculator to find out when the Moon and planets rise and set in your sky.