A large solar flare emitted into space Friday sent waves of charged particles towards the Earth’s atmosphere. The result, a powerful geomagnetic storm that caused the Aurora Borealis, or the northern lights, to be visible as far south as Arizona, Oklahoma, Texas, and Virginia.
For us, cloud cover played a huge role into whether or not you were able to get a glimpse of the northern lights. Luckily, clouds broke apart shortly after sunset, giving us a partial view of the lights for a couple of hours. If you set up shop in areas across extreme northwest Illinois and southwest Wisconsin, you hit the jackpot as skies were clear for much of the event. At times, green pillars danced across the night sky, followed by shades of purple and red.
In a similar fashion to the Storm Prediction Center and the National Hurricane Center, the Space Weather Prediction Center also has a color-coded scale that rates the intensity of these geomagnetic storms. They are rated from G1 (Minor) to G5 (Extreme), and are based off of the possible navigation and radio impacts as well as how often such events occur. At times, last night’s storm hit the G4 (severe) category, hence why so many were able to view them.