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Watch for Mercury, too, as 2021 ends

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John Jardine Goss

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Deborah Byrd

and

December 28, 2021

Watch for Mercury: Sky chart with slanted green line of ecliptic, with planets along it, Mercury and Venus near bottom. — In late December 2021, Jupiter, Saturn, Venus and Mercury are all clustered near the sunset. Watch for Mercury, the sun’s innermost planet, near Venus. Both will be very near the sunset horizon. Can’t see Mercury? Try binoculars.

Watch for Mercury after sunset

The sun’s innermost planet, Mercury, is nowhere to be found for most of December 2021. Presently, it has been moving around the far side of the blinding sun, as seen from Earth. So it’s been crossing the sky with the sun during the day for us on Earth. However, the last several evenings of 2021 may bring Mercury into view for you. Mercury is now moving out to one side of the sun from our early perspective.

In addition, its angular distance from the sun on our sky’s dome is increasing. So we should glimpse the planet briefly, perhaps 30 minutes after sunset, in the sunset direction, in late December. For this reason, you’ll need a sky that’s clear to the horizon in the sunset direction. And you’ll need to know just where to look. The chart above shows Mercury in relationship to Venus, Saturn and Jupiter in the western twilight.

Also, you have to look at the right time! Ideally, look soon after sunset. Mercury (and Venus) will soon follow the sun below the western horizon.

Love the night sky? Keep track of the moon with EarthSky 2022 lunar calendars. Now available! They make great gifts. Going fast!

How to see Mercury

In late December, as Mercury comes into view, Venus will be almost gone from view, heading into the sunset glare, about to pass between us and the sun on January 9, 2022. Venus is bright, though, so you’ll spot it just above your western horizon. As of now, for us in the Northern Hemisphere, much-dimmer Mercury lies to the left of Venus. Indeed, it might appear too faint to be easily noticed. Binoculars will be a great help in identifying this little world. If you spot them both, just imagine, in one view you’ll have seen the two closest planets to the sun!

For this event, Southern Hemisphere stargazers will have no better a view than Northern Hemisphere observers. But hopefully we’ll all snag Mercury if we try!

Bottom line: Watch for Mercury as 2021 ends. Jupiter, Saturn and Venus will be strung out in a line in the western twilight sky. Mercury will be at the bottom of this line, near the sunset point.

Planet-observing is easy: Top tips here

EarthSky’s monthly planet guide: Visible planets and more

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December 28, 2021

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John Jardine Goss

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About the Author:

“I can sometimes see the moon in the daytime” was a cosmic revelation that John Jardine Goss first discovered through personal observations at age 6. It shook his young concept of the universe and launched his interest in astronomy and stargazing, a fascination he still holds today. John is past president of the Astronomical League, the largest U.S. federation of astronomical societies, with over 20,000 members. He's earned the title of Master Observer and has authored the celestial observing guides Exploring the Starry Realm and Carpe Lunam. John also writes a monthly stargazing column, Roanoke Skies, for the Roanoke Times, and a bimonthly column, Skywatch, for Blue Ridge Country magazine. He has contributed to Sky and Telescope magazine, the IDA Nightscape, the Astronomical League’s Reflector magazine, and the RASC Observer’s Handbook.

Deborah Byrd

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About the Author:

Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Prior to that, she had worked for the University of Texas McDonald Observatory since 1976, and created and produced their Star Date radio series. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. In 2020, she won the Education Prize from the American Astronomical Society, the largest organization of professional astronomers in North America. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.