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Lambdalana
2003-Nov-03, 02:26 PM
There is currently a discussion in my astronomy group about this phenomenon.
Do we have the capacity to hear aurorae?

itsmebaby76
2003-Nov-03, 07:54 PM
Hi,
I've heard from folks who have experienced the northern lights in Sweden that there is a slight "static" sound to them. Sort of a "pffft." Don't know how pronounced that sound would be though. ;) B)

Guest
2003-Nov-03, 08:41 PM
I lived in Goose Bay Labrador for several years. While there I saw spectacular aurora on many occasions. There was no audio component associated with the display that was decernable with the naked ear. (Goose bay is an issolated, rural place with little or no background din) Perhaps you could "hear it" with radio equipment tuned to an appropriate frequency.

Biret Máret Kallio
2003-Nov-03, 09:11 PM
If I am a human - and I certainly think I am - the answer is "YES!".
I have heard "Guovssahasat" (Saami for Northern Light) once a
very frosty winter night in the middle of "Basse Aske" (Holy Moon)
- the moon that is lit closest to Midwinter Solstice. The Northern Light
made a crackling, electrifying sound, and it seemed to touch the Earth.
This happened in Vuovdáguoika / Outakoski on the Finnish side of
the border in Saami Land.
With greetings
Biret Máret

Alaskan
2003-Nov-03, 09:46 PM
I live here in Fairbanks, Alaska where the University of Alaska does it's world class Aurora research. Here is the Link (http://www.gi.alaska.edu/cgi-bin/predict.cgi)

After 28 years of observing the Aurora I have never heard anything but local lore says that sometimes early miners claimed to have heard it.

The Aurora when it is active has two components, one in the northern hemisphere and it's doppleganger in the southern hemisphere.

As a ham radio operator I have frequently "heard" the characteristic warble that the aurora causes on radio signals, particularly cw or code signals. Aurora "E" skip could be responsible of extending the distance of some communications and certainly is responsible for restricting certain forms of communication too. I have suspected that auroral influence has allowed me to send a low powered VHF signal over the top of the North Pole into europe by way of low altitude satellites on some occasions too.

MarQ
2003-Nov-04, 05:15 PM
I've heard aurora once, in NOrthwest Ohio in the early '70s. But I'm impressed that those who live in the aurora lands, and who've studied it in Alaska for decades, haven't heard a noise.
Is this a phenomenon that needs another "right" element, like a wind blowing toward the observer, or some certain temperture or barametric pressure?
I'll never forget it, as it came out of a red curtain andhad a moaning, freight train sound familar to me in the farmbelt.
Everyone who's seen aurora the past week down here in Dixie, I always ask if they heard anything and everyone says no.

Alaskan
2003-Nov-04, 08:57 PM
MarQ, here is the Link (http://www-pw.physics.uiowa.edu/mcgreevy/) to the University of Iowa's auroral sound section. Perhaps you might have heard an aurora after all.

Although these sounds are in the Very Low Frequency band, some people do have hearing outside of normal parameters. Then again there may have been something nearby to re-radiate the signal in a higher frequency that normal human ears could hear?

DippyHippy
2003-Nov-05, 03:16 AM
I think some people can hear them, yes... I've heard too many stories where people have said they have been able to hear the static noise described above.

I also think that it's perfectly natural and understandable for some people to hear some things that others can't. I can sometimes hear a very high pitched noise from television sets (I think it depends on the set itself) and yet those present claim not to hear anything. I thought I was weird (okay, I am LOL) until a work colleague said he could hear it too LOL

I'd love to be able to hear the sound of an aurora... but I don't think I'll ever be that lucky...

Matthew
2003-Nov-05, 10:36 AM
I'd love to be able to hear the sound of an aurora... but I don't think I'll ever be that lucky...

I'd love to see an aurora!

Aurora may have a frequency around 20000 Hz, if that is so then only those with the best of hearing would be able to hear it. And only very softly.

Ardh
2003-Dec-31, 08:42 AM
Originally posted by Biret Máret Kallio@Nov 3 2003, 09:11 PM
The Northern Light
made a crackling, electrifying sound, and it seemed to touch the Earth.


The human brain is an amazing creation.

Based on the quote above, it is possible that your brain perceived the aurorae
and connected it somehow to electricity ( i don't know what, perhaps some 'electrical' experiment in school). And this association also made you hear an imaginary sound which you always unconsciously relate to electricity, hence making you imagine the so-called aurorae sound.

Who knows, your brain might have linked it ( unconsciously) to lightning?

This is a mere speculation based on my medical knowledge, consider it a mere opinion if you wish.Thanks. :rolleyes:

Dan Luna
2003-Dec-31, 11:48 AM
Originally posted by DippyHippy@Nov 5 2003, 03:16 AM
I can sometimes hear a very high pitched noise from television sets.
I occasionally get this with computer monitors at work - setting the screen refresh rate a bit higher seems to push the frequency up out of hearing range.

TheThorn
2004-Jan-01, 02:57 AM
I've seen many auroras, and never heard anything, but I've read reports of people who claim that they have.

People have also reported hearing meteors.

But consider lightning, how you hear the thunder some seconds after you see the lightning, depending on how far away it is. The speed of sound and all that - about 5 seconds of lag for every mile of distance.

And then consider that meteors and auroras are tens of miles high in very thin atmosphere. There would be minutes of lag between a meteor or auroral surge and the arrival of any sound that it caused. Yet the people who claim to have observed these sounds say they are instantaneous. So they can't be hearing sound waves that came from the aurora or meteor.

One theory that I've read that there is some sort of electro-magnetic radiation generated by the aurora or the ionization around the meteor, which is picked up by certain people's bodies (or dental fillings, or zippers on their clothing, or metal fences nearby, or...) They refer to this as electrophonic sounds.

Here's a link to a bunch of observations of sounds from the leonids in 2001

Leonid Meteor Sounds (http://www.spaceweather.com/meteors/leonids/2001/sounds.html)

And here's one about sound and auroras:

Aurora Borealis (http://fusionanomaly.net/auroraborealis.html)

But, like I said, I live in a northern area with clear dark skies and I've seen lots of auroras and meteors, and I've never heard anything (and I have LOTS of fillings) ;)