People living in southern parts of Canada could be in for a colourful treat Thursday evening, as a solar storm set to reach Earth was expected to result in a display of the northern lights.

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It would certainly be a rare treat, as the lights are seldom seen in the heavily populated south. Here’s what you need to know about the northern lights, also known as the Aurora Borealis.

What’s the Aurora Borealis?

The bright display of shifting light occurs when charged particles from the sun are thrust along Earth’s dominant magnetic field lines and dive into the atmosphere, colliding with oxygen, nitrogen and other gas molecules. The collisions result in the oxygen and nitrogen molecules becoming excited, and as they return to their normal state they emit photons -- small bursts of energy in the form of light.

Why could we see them in the south on Thursday evening?

The Aurora Borealis is most often seen on clear winter nights in an area known as the auroral zone or the aurora oval, a constantly shifting space that most often encompasses Canadian areas closet to the North Pole. But a strong solar flare that was shot from the sun late Tuesday, and that reached Earth Thursday, is expected to shake up Earth's magnetic field, expanding Aurora Borealis southward.

People as far south as Toronto were expected to see the lights Thursday -- though there’s no guarantee.

What’s the best way to see them?

If your area falls into the aurora oval on Thursday, the first thing you should do is hope for clear skies -- cloudy weather will certainly hamper your ability to see the Aurora Borealis. But if it’s clear, the best thing to do is get somewhere dark, as far away from ambient light as you can, says Jennifer West, an observational astronomy instructor at the University of Manitoba.

“If you can, get away from the city,” she told CTVNews.ca. “If you’re in the city, you might mistake it (Aurora Borealis) for lights in the city.”

West said even going to an isolated place, such as a football field, will improve your chances of seeing the lights.

Regardless of where you are, West says the lights will be in the northern part of the sky. So if you can’t get too far outside the city, go the city’s northern edge. This will limit the amount of ambient light that could interfere with a clear view.

But climbing to higher ground is likely useless, West says, as most city lights actually emit light upwards.

What can I expect to see?

West said it’s not very hard to distinguish Aurora Borealis from other light.

“It tends to have a greenish glow, but not always. The colour of the light depends on the energy of the particles -- what kinds of molecules are being excited,” she said. “But usually we see a greenish glow for most displays. City lights tend to be orange.”

West said another distinguishing feature of Aurora borealis is that it is often on the move.

“You can see curtains, or waves of light, as these particles are travelling through the atmosphere,” she said.