Those who see the aurora borealis may wonder if they can hear the sounds that accompany the lights. The answer to this question is yes, but scientists have not been able to definitively explain what the sounds are. This is why citizen scientists are trying to shed light on this mystery.
The sounds of the northern lights are thought to be produced by the temperature inversion layer. This occurs when the cold air that sits at the bottom of the inversion layer is forced to rise above the warm air that lies above the ground. This creates a field of static electrical potential, which then expands up toward the sky. The resulting electric discharge creates sparks that emit aurora sounds.
Some scientists argue that the sounds are caused by the aurora itself. The motion of the aurora may change the magnetic field on Earth. In this way, the particles that create the lights interact with the particles in the atmosphere, causing the sounds.
Other scientists believe that the sounds are caused by the interaction between the charged particles that create the light and the Earth's magnetosphere. When the Earth's magnetic field lines meet the particles from the sun, they channel them to the poles. This creates a dazzling light show.
Researchers are still trying to find the source of the auroral sounds. The sounds are reported to originate from 70 to 100 meters above the Earth's surface, which is equivalent to about 230 to 330 feet above the ground. They last for several minutes during an auroral display.