There’s a chance Canada will enjoy a light show on Thursday night.
The Sun has fired three coronal mass ejections (CMEs) that are on their way to Earth.
CMEs are large ejections of particles from the sun that travel faster than normal in the solar wind. When those particles reach Earth, they interact with our magnetic field and can create beautiful northern lights, also known as the aurora borealis (or, if you’re in the southern hemisphere, aurora australis).
They often occur after a solar flare, where magnetic fields intertwine and then break up, releasing intense bursts of radiation, which can disrupt high-frequency radio signals here on Earth.
“We have three solar storms headed toward Earth coming one after the other, all in the last 24 to 36 hours,” said Tamitha Skov, a space weather physicist and professor at Millersville University in Pennsylvania, in a youtube update.
The three CMEs were released from the same sunspot area, called 4246.
According to the US National Oceanic and Atmospheric Administration’s Space Weather Prediction Center (SWPC), there is a possibility of a moderate geomagnetic storm late on October 16, Greenwich Mean Time, which is four hours ahead of Eastern Daylight Time and seven hours ahead of Pacific Daylight Time.
That means it could be a problem for those in the West hoping to see the show.
Take solace, though: It’s very difficult to predict exactly when the storm might hit. It could be earlier or even later than expected.
But the SWPC also noted that the storm could perhaps continue into Friday, although it would likely be a weaker storm.
Manage expectations
If you expect a spectacle like those that took place in May and October 2024, this storm will not be as strong.
The scale for geomagnetic storms ranges from G1 to G5, with G5 considered extreme, which is what we saw with those storms last year. The “northern” auroras were seen in all cities and even the Caribbean.
For this storm, the SWPC is forecasting a G2, which is considered moderate.
Still, you can increase your chances of catching them by trying to get to a place with dark skies, away from city lights and with a good view of the northern horizon.
But some things have to align for the northern lights to be visible further south in latitude than where they are normally visible, particularly in the far north.
First of all, CMEs have to be aimed at Earth, as they appear to be. Second, the solar wind must be very fast. And probably most importantly, the aurora hole, along which the particles travel, must be facing south. The further south you dive, the further south they will be visible.
If you want to know if the Northern Lights are visible in your location, you can download apps like Aurora Alerts and Aurora Forecast.
