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Illustration: Chris Brackley/Canadian Geographic; Sources: Robyn Fiori/Canadian Space Weather Forecast Centre, Geomagnetic Laboratory of Natural Resources Canada

“Showtime!” Roger Woloshyn, a presenter at the Churchill Northern Studies Centre, in Churchill, Man., bellows as he walks down the hallway rapping on the bedroom doors of visitors who don’t immediately answer or snap to action.

Here, less than one kilometre from the icy shores of Hudson Bay, it is -35°C outside. But on this Friday evening in late March, the intrepid visitors who venture out onto the rock-solid northern tundra will be rewarded. Far beyond the Earth’s atmosphere, a fresh batch of charged particles recently burst from the surface of the sun, nearing the end of a 170,000-year journey that started at the sun’s core. The mass of matter and energy has radiated nearly 150 million kilometres through space on its way to triggering a light show over northern Canada. This evening’s aurora borealis above Churchill will be one to remember.

Twenty kilometres east of Churchill and on the edge of Wapusk National Park — Parks Canada’s denning sanctuary for nursing polar bears — the Churchill Northern Studies Centre has become a major stop in a growing aurora borealis tourism trade in Canada, along with Whitehorse and Yellowknife, where northern lights tour vans have been traded in for top-of-the-line buses.

Woloshyn has been coming to Churchill for more than 20 years to share the northern lights with eager “polar fleece stargazers.” By studying space weather predictions from days before, Woloshyn learned of the sun’s latest coronal mass ejection (a burst of solar wind and magnetic fields released into space), heading on a direct course for Earth. Tonight, he has studied satellitebased imagery of the auroral oval, part of which has been hanging over Churchill since before dinner. After going outside to visually confirm what he’s picked up from the satellite photos, Woloshyn excitedly makes the rounds and prepares to take his group outside for what could be the night of their lives.

For aurora tourists and space scientists alike, 2013 promises to be a stellar year. Solar activity — flares, sunspots, solar winds and other forms of radiation — is governed by changes in the sun’s magnetic field. These activities wax and wane on a fairly predictable 11-year cycle known as the solar maximum. The peak of this cycle hits this year (predicted to be September 2013 or later), which is why skywatchers and scientists are so excited. The solar maximum should bring with it the brightest and most frequent auroral displays for more than a decade. It will also give scientists the chance to examine aspects of space weather at its most violent and to measure its impact on the Earth infrastructure, such as electrical grids and communications.

Over the past 100 years, scientists have expanded our knowledge of auroras with insights into their origin in the sun and their interactions with the Earth’s atmosphere. Auroras are often associated with Earth-sized or larger sunspots (“holes” of magnetic disturbance on the sun), through which solar flares or huge looping flames called prominences erupt. If one of these “energy volcanoes” on a part of the sun is pointed toward Earth, the ejected material arrives on our doorstep in roughly half a week, about the time it takes an Amazon.ca shipment to travel between major cities.

When the eruption’s solar wind — plasma made up of ionized (positively or negatively charged) hydrogen atoms — hits the Earth, it’s travelling at hundreds of kilometres per second. Like iron filings being drawn to the poles of a bar magnet, the solar wind swirls into our planet’s magnetic fields near the North Pole and South Pole, setting in motion a sort of atmospheric dynamo. As these charged particles begin to move at hundreds of thousands of kilometres per hour, like great atomic tornadoes, they spin down along magnetic field lines into the Earth’s ionosphere (the region in which the International Space Station orbits). Eventually, they near the speed of light and become unstable, reacting directly with the planet’s magnetic field. At this point, the ionized atoms, up to now in an excited state, return to a non-excited state, creating so much heat in the process that they glow — green and sometimes red for oxygen and blue or pink for nitrogen.

On a global scale, this glowing takes the form of the auroral oval, a halo of light centred over the Earth’s geomagnetic poles. Earthbound observers watching this process see only a portion of the whole auroral oval when they’re treated to the dancing curtains of light known as the aurora borealis in the northern hemisphere and aurora australis south of the equator.

As luck would have it, Canada is the geographical hub of activity for auroral and space weather research. That’s because the Earth’s geomagnetic North Pole is shifted roughly 10 degrees down toward Hudson Bay from its geographical North Pole. “It’s not that we have just a slightly better view,” says University of Calgary space physicist Eric Donovan. “You have this oval that cuts across southern Greenland, Iceland and the very northern tip of Scandinavia, then skirts along the northern coast of Russia, comes down across Siberia and Alaska and cuts right across Canada. I would say 80 to 90 percent of the readily accessible land under the auroral oval is in Canada. We have a geographical situation where we can do things that others can’t.”

Beginning in the 1950s, Canadian researchers started to study the northern lights from the inside out by firing specialized “sounding rockets” into the aurora from Churchill and other locations. Half a century later, as a result of several generations of hard work and innovation, the Canadian North is populated with dozens of networked sensors that can capture data from below, confer with satellites high above and assemble a big-picture view of nearly the entire auroral oval, live, as it hangs over the northern hemisphere.

Since those early days of blasting rockets into the aurora, Canadian scientists have refined techniques that make use of radar, visual-light and multi-spectral cameras, Global Positioning System devices, magnetometers and other sensors, becoming world leaders in near-Earth space research. As the sun’s once-a-decade peak season kicks into high gear, those researchers will be ready with a network of space weather monitors larger and more powerful than any brought to bear during previous solar maximums.

For scientists such as Donovan, auroras are more than just pretty night skies. “What first hooked me on this research was the idea that I could use these visual images of the aurora to do plasma and magnetospheric physics,” he says. “I always loved the aurora but never connected it with what I was already researching. Then I looked at early images, where I could see things that were clearly unexplained and were related to the dynamics of the magnetospheric region of space around the Earth. So I was just captivated by the beauty of it and the possibility that I could link this beautiful thing to the things I have been trying to study.”

Donovan is the team leader and principal investigator for more space weather observation projects than anyone else in Canada. He oversees a growing network of nearly 60 instruments that study the aurora in northern Canada — the largest such effort on Earth. From his University of Calgary lab, which is more of a repair shop for an endless parade of different sensors and detectors, to his “lab” that spans several million square kilometres of the Canadian Arctic and subarctic, Donovan and team are ready to capitalize on the storm season in space.

“We have buildings and sheds and huts and aluminum tubing and cameras in places ranging from Happy Valley- Goose Bay in Labrador, to Rankin Inlet in Nunavut, to Inuvik, in the Northwest Territories,” he says. The latest addition is a $25 million installation curently being built in Resolute Bay, Nunavut, known as the Resolute Incoherent Scatter Radar-Canada (RISR-C). When completed, RISR-C will be an arena-sized array of sensors used for studying the properties of the Earth’s upper atmosphere. Donovan and his team also have colleagues running cameras for them in the Faroe Islands, Iceland and other locations, and are quickly forging new relationships from Greenland to China.