Finnish Researchers Locate Creation of Auroral Sounds

Folktales and wanderers described varied subtle sounds coinciding with distance sightings of aurora borealis lights. For the first time, scientific researchers have discovered the source of sounds' source. As reported by esciencenews.com:  "The auroral sounds that have been described in folktales and by wilderness wanderers are formed about 70 meters above the ground level in the measured case. Researchers located the sound sources by installing three separate microphones in an observation site where the auroral sounds were recorded. They then compared sounds captured by the microphones and determined the location of the sound source. The aurora borealis was seen at the observation site. The simultaneous measurements of the geomagnetic disturbances, made by the Finnish Meteorological Institute, showed a typical pattern of the northern lights episodes."

Aalto University Professor Unto K. Laine is quoted on the Aalto website, where you can also listen to a recording of the sounds, saying "Our research proved that, during the occurrence of the northern lights, people can hear natural auroral sounds related to what they see. In the past, researchers thought that the aurora borealis was too far away for people to hear the sounds it made. This is true. However, our research proves that the source of the sounds that are associated with the aurora borealis we see is likely caused by the same energetic particles from the sun that create the northern lights far away in the sky. These particles or the geomagnetic disturbance produced by them seem to create sound much closer to the ground."

Though we now have research demonstrating the sounds and the lights are linked, mechanical details about how the various sounds - described as distant crackles, muffled bangs and sputters - are created remain a mystery. 

Image: "Aurora Borealis: the colored lights seen around the North Pole, the Northern Lights, as seen from Bear Lake, Alaska" (link) by Betty & Pack on Flickr courtesy of Creative Commons Licensing.