Sounds associated with the northern lights have been called fleeting and very weak.
Researchers from Aalto University say they compared sounds captured by three microphones where auroral sounds were recorded.
They say the crackles or muffled bangs are generated about 230 feet above ground level, probably by the same energetic particles from the sun that create the northern lights 60 to 200 miles aloft on the edge of space.
Much is left to learn about the auroral sounds as they don’t occur every time the northern lights are seen.
They are also so soft that it is difficult to hear them and to distinguish them from background noise.
Photo: Akhmetsafin Ruslan