As night fell on May 10, 2024, millions of curious people across the globe ventured outside in hopes of catching a glimpse of the northern lights in the darkness — and better yet, capturing a spectacular photo. Previously visible only in arctic regions, this phenomenon came into view as far south as Alabama and California as the night’s aurora borealis revealed itself, etching the moment into our memories. And it all became possible thanks to solar activity being at nearly a 20-year high.
But what was a sense of beauty and wonder for many also served as a time of concern and even angst for those who either provide or rely on accurate positioning from satellites. This unusual phenomenon was caused by a G5 level geomagnetic storm that lasted two days — making it the most significant geomagnetic storm descended on Earth since 2003. NOAA’s Space Weather Prediction Center measured its Estimated Planetary K-Index (Kp index) — a common metric-based gauge for geomagnetic storms — on a 9 point scale, on which it hit maximum values at various monitoring stations.