From Aalto University , something I’ve always wondered about but could never hear myself. They have a video of aurora, complete with sounds which follows below. I wonder if this isn’t something akin to thunder, where magnetic or static field lines create a sound once they fade or collapse. – Anthony
Sounds of northern lights are born close to ground
For the first time, researchers at Aalto University in Finland have located where the sounds associated with the northern lights are created. 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.
“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,” said Professor Unto K. Laine from Aalto University.
Details about how the auroral sounds are created are still a mystery. The sounds do not occur regularly when the northern lights are seen. The recorded, unamplified sounds can be similar to crackles or muffled bangs which last for only a short period of time. Other people who have heard the auroral sounds have described them as distant noise and sputter. Because of these different descriptions, researchers suspect that there are several mechanisms behind the formation of these auroral sounds. These sounds are so soft that one has to listen very carefully to hear them and to distinguish them from the ambient noise.
The Aalto University researcher’s study will be published in the proceedings of the 19th International Congress on Sound and Vibration. The congress is held in Vilnius, Lithuania from 8 to 12 July 2012.
For more information, please contact:
Professor Unto K. Laine
Aalto University, School of Electrical Engineering
tel. +358 9 470 224 92
Researcher’s website: http://www.acoustics.hut.fi/projects/aurora
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I was expecting a symphony… how deceptive!
Anthony: It sounds like a whip crack.
REPLY: Yeah, a whip crack is caused by supersonic speed – a small sonic boom. Thunder is produced by the collapse of the superheated air channel surrounding lightning bolts.
Source: http://www.lightningsafety.com/nlsi_info/thunder2.html
Maybe some sort of small scale sonic thunder like event is going on here with aurora electrified cold air. – Anthony
I never heard a clapping sound, but when I was younger there was a high frequency hissing that waxed and waned in synchrony with the visible movements of the aurora. Either my hearing has declined with age, or I have too rarely been able to view the aurora in a quiet non-urban area, or both, since I have not heard aurora in many years.
I heard a 2-3 hz sound once that lasted for a few minutes.
I grew up in Canada’s back country away from towns and cities as a Native kid – it was common to “hear” the Northern Lights in my world. Something I never mentioned to this day – Native elders used to say our ancestors are talking to us from beyond. However, here in the white world where I was educated THAT is something you never mention – Northern Lights have sounds – never hear of any white person mentioning that fact until now. Guess I wasn’t crazy after all.
Makes sense. Aurora ionizes air, and ions behave pretty much the same as electrons in a conductive metal. Moving magnetic fields cause the aurora, and those moving fields should also cause currents in the ionized air molecules near the ground. And moving air molecules = sound by definition.
albertalad says:
July 9, 2012 at 9:15 am
However, here in the white world where I was educated THAT is something you never mention – Northern Lights have sounds – never hear of any white person mentioning that fact until now.
My little brother (yup, he’s white) was a field agent for USF&W in the Anchorage office for fifteen years — he’ll talk your ears off about aurora noise…
“GlynnMhor says:
July 9, 2012 at 9:12 am
I never heard a clapping sound, but when I was younger there was a high frequency hissing that waxed and waned in synchrony with the visible movements of the aurora. Either my hearing has declined with age, or I have too rarely been able to view the aurora in a quiet non-urban area, or both, since I have not heard aurora in many years.”
These are exactly the sounds I heard on several occasions when in Labrador City (approximately 55 Deg. North) on business. I’m glad to hear I’m not the only one hearing Aurora noises.
I’m with Glynn Mhor.
This sound is way more then a folk tail. My hearing did not allow me to hear it but I was with several children and they could hear it. This on more then one occasion and with different people. It is nice to know science has now confirmed that whey we northerners have always known.
Nonsense, it’s tinnitus you hear from too much gun shooting without hearing protection 🙁
In northern BC it is the hissing I hear. People never made a big deal about the noise as it is a given along with the lights. The hissing seems to be related to the size and brightness of the lights and comes in waves.
I have also heard the sounds. In northern Greenland, where the Aurora was to the south, and in Alaska where it was overhead.
I wonder if it a similar mechanism that enabled me to “hear” some meteorites: typically a thin hissing with some muffled popping sounds. The sounds from the meteorites never made any sense since they were coincidental with the viewing. The only way it made sense if the sound had been produced by some electromagnetic mechanism.
Is there a frequency and intensity difference between Northern and Southern light? And is there a difference in frequency and intensity between green and red aurora lights?
I’ve watched lots of displays from north of the Arctic Circle and never heard squat. The natives taught me that if you whistle, the lights will move. I found that to be generally true, but suspect it had more to do with what whistling does to the observers eyeballs than some cosmic mystery.
My dad did his Army basic training in Churchill, Canada back in the mid-1950s, and often told us how he would lie out at night in his sleeping bag and listen to the Northern Lights crackling overhead.
I hope their instrumentation was shielded to Tempest level so that their results are not questionable. Microphones of the moving coil type will pick up EM interference, improperly shielded cables will also. I also saw the Aurora Australis when I was much younger and had better hearing. I don”t remember hearing it but I do remember that it was a lot more colourful.
This thread brings back memories. Ages ago when I was doing instrumentation for large conventional weapons I remember hearing a pop simultaneous with the fireball even though it was far away. We also discovered that conventional explosions also produced the zip ( EMP ). I just found this article which may explain somethings: http://www.dtic.mil/dtic/tr/fulltext/u2/a195644.pdf
At last one must not be ashamed of hearing the aurora sound! However I do not recognize exactly the recorded sound here. To me it has been more like crackling and hissing from everywhere. It is not heard every time even during intense auroras and like the optical manifestations it is seldom the same from one time to another.
Now I look forward to have the fireballs in thunderstorms observed by scientists too. Perhaps even explained.
Cool stuff.
I’m still trying to see my first Green Flash. Not convinced that is real yet either because I haven’t seen it.
Ray asks “Is there a frequency and intensity difference between Northern and Southern light? And is there a difference in frequency and intensity between green and red aurora lights?”
So far as I am aware, there is not difference between North and South. The aurora is caused by “forbidden” transitions in the atoms of the atmosphere. The green is a nitrogen line, and the red oxygen. So far as I know, no-one knows why forbidden transitions occur, but not the normal ones.
otsar. I suspect your comment about Tempest shielding is very valid. There is an alternate theory that the “sounds” are, in fact, a similar phenomenon going on in the electrical circuits of the human brain.
Well Jim,
You guys should all put in a few coins each and send me to listen up there as my electrical circuits are not attached at all correct and should I listen and hear the sounds that would disprove your theory and advance science correctly.
Reminds me of plasma “loudspeakers”, just something else I’ve never quite understood how it worked.
http://www.easternvoltageresearch.com/plasmaspeaker.html
If that were the case, common household appliances (never mind ham radio emissions) should be able to produce the same effects (whether when simply running or upon power-up or power down when ‘surges’ exist including ham radio where the operator or family members may be in the stronger *near fields* of say an 80 meter dipole strung over the house where the E and H fields can be much, much stronger than that from the AB), but, alas they do not … hence I am leery to buy that effect (that AB EM ‘effects’ are taking place directly upon the brain ordirectly into the nervous system or directly into any sensory organ except via their intended method of ‘excitation’ e.g. actual sound, actual sight of phenomenon, or associated ozone smell etc) here ….
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