Northern lights were seen in Calgary on Monday evening due to a strong geomagnetic storm that started over the weekend. This storm made the auroras visible even within the city.
The U.S. National Oceanic and Atmospheric Administration (NOAA) issued a G3 storm watch for late October 7 and early October 8 because two bursts of solar energy, called coronal mass ejections (CMEs), passed Earth. NOAA explained that these CMEs can cause geomagnetic storms.
Aurora borealis was seen from south Calgary on Monday, October 7, 2024. Image by calgaryherald.com
The CMEs came from a sunspot explosion that happened on Thursday, which produced the strongest solar flare in the current 11-year solar cycle. This event led Space Weather Canada to issue a major storm watch. The radiation from the flare also caused a shortwave radio blackout over Africa.
A person takes a photo of the northern lights in Vancouver: Image by Calgary.citynews
On Monday, NOAA’s Space Weather Prediction Center predicted that northern lights could be visible across most of Alberta, depending on local conditions. The storm was also expected to produce auroras as far south as Illinois over the weekend. Such multi-day G3 storm watches are rare but not unheard of, according to NOAA.
Calgary is located close enough to the auroral zone, especially during strong solar activity, which allows for the possibility of seeing the lights if the sky is clear.
Space Weather Canada warns that strong geomagnetic storms can affect technology. They may disrupt radio signals, damage satellites, and interfere with GPS navigation. Additionally, these storms can cause electric currents in power lines and pipelines, leading to power outages or corrosion.
