In early November 2023, sky watchers across North America and Europe posted photos on social media of dazzling displays of the northern lights, also known as the aurora borealis. Colorful ribbons of light filled night skies, incited by a strong geomagnetic storm in Earth’s magnetosphere.
The VIIRS (Visible Infrared Imaging Radiometer Suite) sensor on the NOAA-NASA Suomi NPP satellite captured this image of the aurora over western Canada at 3:23 a.m. Mountain Time (10:23 Universal Time) on November 5, 2023. The aurora was so bright near Edmonton, Canada, it nearly saturated the satellite sensor. The event continued into the next evening, when skies in Glasgow, Montana, danced with pink and green light. The lights were especially bright near the U.S.-Canada border and in Alaska, but they were also faintly visible as far south as Texas.
The creation of an aurora typically starts when the Sun sends a surge of charged particles—through solar flares, coronal mass ejections, or an active solar wind—toward Earth. The solar particles collide with the magnetosphere and compress it, changing the configuration of Earth’s magnetic field. Some particles trapped in the magnetic field are accelerated into Earth’s upper atmosphere where they excite nitrogen and oxygen molecules and release photons of light, known as the aurora.
Read more at NASA Earth Observatory
Photo Credit: JHGilbert via Pixabay