IN SPACE – SEPTEMBER 9: (FOR EDITORIAL USE ONLY) In this photo for printout provided by European Space … [+] Agency (ESA) On September 9, 2014, the German astronaut of ESA Alexander Gerst made this image of aurora borealis while orbiting the Earth while aboard the International Space Station (ISS). Gerst returned to Earth on November 10, 2014, after spending six months on the International Space Station, completing an extensive science program known as the Blue Dot mission. a Voyager-made probe six billion kilometers away). (Photo by Alexander Gerst / ESA via Getty Images)
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Can aurora borealis “speak”?
If you stand outside under a clear sky while a geomagnetic storm rages above you, the sounds you are likely to hear are happy with others chasing the Northern Lights. However, in addition to the strange “wow” and the click of the camera shutters, there have been myths and legends for centuries that the glow itself makes a sound.
Assumptions that the aurora borealis – which occurs in the Earth’s ionosphere hundreds of miles up – comes with whistling or whistling, popping or hissing, can be found in accounts from Greenland, the Shetland Islands, northern Canada and Norway. “It was as if two boards had met on flat roads – not a sharp crack, but a dull sound loud enough for everyone to hear,” according to one story.
Rejected as psycho-acoustic phenomena – the scientific word for “you imagine it” – new records from Aalto University in Finland suggest that there is a strong link between geomagnetic fluctuations and “auroral sounds”.
The northern (and southern) radiance is caused by the solar wind in space – charged particles from the sun – which accelerate down the lines of force of the Earth’s magnetic field. Green lights are caused by charged particles that collide with oxygen molecules, while other colors are caused by nitrogen molecules.
It is assumed that, when the circumstances are right, it is possible for a pocket of warm air about 75 meters above the ground to hold a retained static charge, which discharges when the air is dissipated. Hear occasional cracking or popping.
It is related to geomagnetic conditions, so it is related to radiance, but sound can occur even when aurora borealis is not visible. This was a surprise, because legends have always associated with sounds only strong, vivid manifestations of the northern lights just above the observer.
“This negates the argument that auroral sounds are extremely rare and that aurora borealis should be extremely bright and vibrant,” said Unto K. Lane, an honorary professor at Aalto University and lead author of a new publication presented at the Baltic Nordic Acoustic Meeting in Aalborg, Denmark.
Lane recorded four hours of polar sounds near the village of Fiskars, Finland, about 90 kilometers west of Helsinki.
There was no depiction of the Northern Lights that night, but when the sounds of the recordings were compared to measurements of geomagnetic activity by the Finnish Meteorological Institute, there was a strong correlation. According to the document, the 60 best candidates for “auroral sounds” are related to changes in the geomagnetic field.
The correlation was so accurate that Lane thought he could predict when the Northern Lights would make a sound. “Using geomagnetic data that has been measured independently, it is possible to predict when auroral sounds will appear in my recordings with 90% accuracy,” Lane said. “Sounds are much more common than anyone thought, but when people hear them without visible light, they think it’s just ice cracking or maybe a dog or some other animal.
Could there be a boom now for people traveling north not only to see the glow but also to hear it?
“It’s interesting because if you look at the Greenland myths about the Northern Lights, they involve whistling or crackling – there was a strong sense that the aurora borealis could speak,” said Tom Kers, author of The Northern Lights: The Ultimate Aurora Guide in this study. “But it’s the white whale of the aurora borealis that I’ve been chasing – I’ve never heard of it.”
The Northern Lights appear as an auroral oval around the North Pole at about 66-69 ° north latitude – the Arctic Circle. The best places to see them are Alaska, Northern Canada, Iceland, Greenland, Norwegian Lapland, Swedish Lapland, Finnish Lapland and Northern Russia.
The Northern Lights’ season is from September to March, if only because it is not getting dark over the Arctic Circle, where they meet mostly constantly. However, you may still be able to hear them …
I wish you clear skies and open eyes.
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