Geminid meteor over the Lut Desert in Kerman, Iran. (Amirreza Kamkar via SpaceWeather.com)
The first meteor shower of the 2020s is set to light up the skies late Friday night into the predawn hours of Saturday morning. The January Quadrantids feature impressive meteor rates and occasional fireballs. But blink and you’ll miss it — the shower’s peak is notoriously short. Here’s how you, too, can enjoy the show.
What makes a meteor shower?
Meteor showers occur when Earth passes through a stream of space-borne debris during the planet’s annual orbit about the sun. Meteor showers take place at roughly the same time every year, because Earth passes through the same debris pocket in the same point in its orbit. That’s why the Perseids happen every August, while the Geminids make their appearance during December.
The debris is usually left behind by a comet or asteroid. Individual pieces of material responsible for creating a shooting star are often barely the size of a Tic Tac. When the stones burn up in Earth’s outer atmosphere, they produce light. The space pebbles that spark the Quadrantids originate from Asteroid 2003 EH1.
What’s unique about the Quadrantids?
A comparison of the peak of the Geminid, top, and Quadrantid, bottom, meteor showers in 2014. Notice the Geminid shower has a much longer peak. (Adapted from International Meteor Organization)
The Quadrantids are a significant meteor shower. They produce meteor rates comparable to those of the Geminids or Perseids. But they don’t stick around long. Their peak lasts only four hours — a stark contrast with the two- or three-day-long spurts of meteor activity of rival meteor showers.
Why is the peak for the Quadrantids so short-lived? It has to do with the width of the instigating debris trail, and the angle at which Earth intersects it. In this case, it’s nearly a 90-degree perpendicular crossing.
Think about your time spent in a shopping mall or supermarket parking lot. Everybody decides to cross in front of you when you’re trying to leave, right?
People who cross straight across the street perpendicular to you take the least amount of time. But then there’s always that one person pushing their shopping cart diagonally across the street, taking three or four times as long. That’s an analogy that helps illustrate the intricacies of meteor shower duration.
When is the peak?
Officially, the peak of the shower is slated for 3:20 a.m. Eastern, 12:20 a.m. Pacific on Saturday. Because the window is narrow, stargazers in most of Europe will probably miss out on this year’s show (parts of westernmost Europe, including the United Kingdom, may catch a short glance before sunrise).
It’s great news for those dwelling in the Americas, however, as the first quarter moon sets about an hour after midnight local time in most spots. It retires below the horizon at 1:10 a.m. in Washington, 1:22 a.m. in Minneapolis, and 12:59 a.m. in Los Angeles.
If the four-hour peak is centered on the 3:20 a.m. Eastern mark, that means the show should really ramp up about two hours before, and taper down two or so hours after the mark. That would put the times to watch between about 1:20 a.m. and 5:20 a.m. Eastern. That’s why this show favors East Coast viewers, as it is squeezed perfectly in between moonset and sunrise. If you can find a clear, dark location, no other celestial objects will obscure the view.
The “radiant,” or the point in the sky from which the meteors appear to emanate, will also be higher in the sky for the East Coast, which means better meteor rates. Western North America will still enjoy a decent show, but a lower radiant could cut back markedly on the number of meteors observed.
How can I enjoy it?
If you’re feeling ambitious, are lucky enough to have clear skies and want to catch the show, you can see it. Just find yourself a clear, dark location with a wide view of the sky. Make sure to be there an hour or so before the scheduled peak in your time zone.
How many meteors will I see?
Where conditions may help chances to enjoy the Quadrantid meteor shower. (Matthew Cappucci/PowerPoint)
That’s a good question. The show is advertised as featuring 100 shooting stars per hour, but don’t trust numbers like that. That’s a Zenithal Hourly Rate. It’s an idealized number assuming absolutely perfect viewing conditions and that you can stare at the entire sky at once without blinking.
Instead, plan for about 20 to 40 meteors per hour, depending on how conditions evolve and the specifics of your viewing location. If at first you don’t see any, don’t give up. It requires patience and a bit of luck. Plus, your eyes need to adjust. Despite being fainter, the Quadrantids tend to be slower streaking across the sky. They move at about 25 miles per second.
Will the weather cooperate?
Let’s hope so! A frontal system will bring widespread cloudiness over the East Coast, the storm’s sky cover lingering as far back as the Mississippi valley. Over the Plains, however, conditions appear ideal.
The West may be socked in beneath some patchy cloud cover, as well.
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