Science

Geminid meteor shower: How to watch the last big show of the year

The most active meteor shower of the year is upon us. Get ready to bundle up and catch some "shooting stars."

Never mind the full moon — go out and try to catch some meteors

The annual Geminid meteor shower is among the best meteor showers of the year. (Macolm Park)

The most active meteor shower of the year — and the final big one — is upon us. 

The Geminid meteor shower runs December 4–16, peaking on the night of December 13. This shower can produce about 120 meteors an hour at its height. 

There's just one problem this year: the full moon.

Unfortunately, that shining beacon in our night sky will be at its fullest on the shower's peak night. Even if you have a clear sky, the moon's light will drown out all but the brightest of meteors.

Though this is the most active shower of the year, it's not quite as popular as the Perseid, the second most prolific meteor shower, with about 100 an hour. That's because the Perseids occur in August, with warmer weather for those in the northern hemisphere. For us Canadians, December means cold and cloudy.

Still, don't let that dissuade you from trying to catch a few meteors. 

Where to go and what to do

Meteors are tiny pieces of debris that burn up in our atmosphere. You can see meteors on any given night, but the ones in showers — which occur almost every month — are brought to us from a comet or asteroid that has crossed Earth's path at some point in its orbit around the sun.

The planet moves through the accumulation of debris, bringing us more frequent meteors across the night sky.

Not all meteors — or meteor showers — are the same. Some meteors can be fast and bright; some produce long tails; and some are fast and dim. In the case of the Geminids, they aren't particularly fast-moving, so don't expect long trails. But they are often bright and intensely coloured, so get ready to see a few green meteors. 

If you're fortunate enough to have clear skies, optimize the experience by getting yourself to as dark a location as you can. That way, even with that moon lighting up the sky, you'll be able to see fainter meteors that aren't also being drowned out by city lights.

The radiant — or the area from which the meteors appear to be originating — is in the constellation Gemini (hence the name), which will rise from the east. Around 2 a.m. the shower will be nearly overhead, but meteors will be seen streaking all through the sky.

Though it may seem obvious, the key is to look up — and keep looking up. When watching an event such as this with someone else, there's a temptation to turn to look at them. But if you do, you may miss out. 

Also, don't use your cellphone, with its bright backlighting. It can take your eyes more than an hour to adjust to the dark — a phenonenon called dark adaptation — but once they do, they'll be able to pick up faint meteors that you might not otherwise see.

Though the shower peaks on the 13th, you could spot meteors before or after, so you can also try on the 12th or 14th.

ABOUT THE AUTHOR

Nicole Mortillaro

Senior Science Reporter

Based in Toronto, Nicole covers all things science for CBC News. As an amateur astronomer, Nicole can be found looking up at the night sky appreciating the marvels of our universe. She is the editor of the Journal of the Royal Astronomical Society of Canada and the author of several books. In 2021, she won the Kavli Science Journalism Award from the American Association for the Advancement of Science for a Quirks and Quarks audio special on the history and future of Black people in science. You can send her story ideas at nicole.mortillaro@cbc.ca.