Scientists are getting closer to understanding what causes the vivid display of the Northern Lights, National Geographic reports. New satellite research indicates that charged particles from the sun are flowing toward Earth’s upper atmosphere in magnetic streams. The waves of charged particles, called solar wind, likely provide energy for the bright geomagnetic storms and auroras.
Researchers made these discoveries while tracking a two-hour light display over Alaska and Canada in May, using satellite and ground cameras. NASA researchers calculated that the auroras traveled twice as quickly as predicted, covering 400 miles in 60 seconds. Scientists compared the storm’s power to a magnitude 5.5 earthquake.