TORONTO – While Canadians have been fortunate to catch a lot of the aurora borealis, or northern lights, over the past year, this time it was the southern hemisphere that was in the right place at the right time.
READ MORE: Why do we get the northern lights?
Those in New Zealand and even Australia were treated to the aurora australis, or southern lights (unfortunately for the people in Antarctica the sun is up all day).
And it came as a surprise.
Aurorae occur when Earth’s magnetic field tips south, allowing particles from the sun to stream into the poles where the particles interact with molecules. We see the released energy as light, or the aurora.
Typically a solar flare and coronal mass ejection (CME) bring the brightest shows as the the influx of fast-moving particles interact with the planet’s magnetosphere. (Auroras can also happen if there is something called a coronal hole in the sun, an area where the sun’s magnetic field reaches out into space, allowing particles to stream out along the solar wind.)
Though a CME was ejected from the sun after a mildly strong solar flare on Tuesday, it was expected to only give a glancing blow to our planet, which could trigger some aurorae, though nothing spectacular. However, it looks like our interplanetary magnetic field tipped south Wednesday just at the right time, opening a crack in the magnetosphere, which allowed the particles to stream in.
Here are some photos of the southern lights seen in New Zealand and Australia.
In parts of western Canada and Alaska, some people braved the cold and the early hours to snap a few photos of their own.
It’s unknown whether or not we’ll see more aurora Wednesday night.
The Kp index, used to measure the disturbance in Earth’s magnetic field, was at 7 during this light show. That is considered very high (in the past few months we’ve seen Kp indices of 4 to 6.) Since then, it has dropped to 4. But you never know. If you’re brave enough to head outside in the frigid temperatures, you might get a light show.
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