How to watch tonight's Geminids, one of the most active meteor showers of the year

It's the final — and some might say the best — meteor shower of the year: the Geminids. Here's what to expect.

Shower could produce more than 100 meteors an hour

The annual Geminid meteor shower peaks on the night of Dec. 13-14. (Mark Almond/The Associated Press/File)

It may be chilly out, but if you bundle up and step outside over the next week, you'll be able to enjoy one of the most active meteor showers of the year: the Geminids.

Though you can spot a meteor on any given night, Earth has a major meteor shower almost every month, when it passes through a trail of debris left over from a passing comet or asteroid.

Each December, we pass through debris from asteroid 3200 Phaethon, which orbits the sun once every 524 days. 

The shower runs from Dec. 4-23, but peaks on the night of Dec. 13-14. Though you can head out any time to catch a few, your best bet is likely from Dec. 12 to the night of Dec. 15. 

During the peak, you can see upwards of 120 meteors an hour as they travel through the atmosphere at 35 km/s. But to do so, you should get to a dark site.

You can use this animation to see how Earth passes through the remains shed by the asteroid.

3200 Phaethon may be something astronomers refer to as a "dead comet," in part because of its highly elliptical orbit around the sun. But astronomers still aren't sure how to classify this intriguing rock as, when it nears the sun, it doesn't produce a tail like comets do. 

Interestingly, on Dec. 16 the asteroid — discovered in 1983 — zips past Earth roughly 10 million kilometres away.

Observing tips

The best thing about this year's Geminids is the moon, or lack thereof, which will be only roughly 14 per cent illuminated on the night of Dec. 13, meaning there won't be any significant bright light to drown out the fainter meteors.

So where to look? You just need to look up. But, there is a direction from which the meteors seem to be coming, called the radiant. This shower's radiant lies in the constellation Gemini, hence the name.

Gemini rises in the east around 10 p.m., but the later it is, the better your chance at seeing some meteors, as the constellation gets higher in the sky where it's darker. And try to stay away from anything bright — including your phone.

So, if you have clear skies and plan to brave the elements, head to a dark location and look up. If you're in a light-polluted city like Toronto or Vancouver, you'll likely still manage to catch some of the brightest meteors, as this shower tends to produce bright ones with great colour. Just try to stay away from streetlights and you're sure to catch a few.

About the Author

Nicole Mortillaro

Senior Reporter, Science

Nicole has an avid interest in all things science. 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.