How One Scientist Decoded the Mysterious Sounds of the Northern Lights

For more than 15 years, a lone scientist in southern Finland has spent countless winter nights among the snowy fields and frozen lakes around his village, in pursuit of one of the most ephemeral mysteries of the heavens: the faint, almost phantasmagorical sounds heard during intense displays of the aurora borealis, or northern lights.

The epic study by acoustician Unto K. Laine includes the first audio recordings of the muffled crackling or popping sometimes heard overhead during spectacular aurora displays.

Over the years, the sounds of the northern lights have been explained as illusions, imagination, inebriation or even voices from the spiritual world.

But Laine has shown the sounds are real, and he thinks he has found what causes them: sparks of electricity discharging beneath the aurora in an inversion layer of the atmosphere that can form in clear and calm weather conditions.

[link to www.space.com]