Listen to the Sky
disposable60 writes "Sky Ear will be a one-night event in which a glowing "cloud" of mobile phones and helium balloons is released into the air so that people can dial into the cloud and listen to the sounds of the sky."
← Back to Stories (view on slashdot.org)
Even better, muck around with VLF/ELF radio. You can hear much more interesting stuff than just the sky, like whistlers from thunderstorms for starters...
Check out vlf.it for some interesting stuff on VLF/ELF radio.
And why wait?? Listen now, live. (not all at once now!!) If that site goes down, and I presume it will within seconds of posting this, this site has pre-recorded sounds of Earth's natural EM radiation.
- "Hear that?! The percolations are imminent! Cease your ingress!"
I have been on the top of a pretty high mountain (Bald Mt, Butte County, CA) during Field Day 2003. The cell had full strength signals but we couldn't make a call. When my friend got his roaming bill it turns out he was hitting a tower about 150 miles away. The better gain antennas on the cell tower could hit us, but out little .3w phone couldn't get back to it.
You're probably referring to the Schumann resonance, the resonance of the earth-ionosphere resonant cavity. Energy from lightning around the world excites this resonance, which then rings--much as hitting a bell with a hammer causes the bell to ring.
Also like an acoustic bell, there is a fundamental frequency of resonance and many overtones that grow fainter as you go up in frequency. The fundamental Schumann resonance is approximately 7.8 Hz; the first few overtones are usually given as 13.8, 19.7, 25.7, and 31.7 Hz. There is a slight variation in the frequencies involved over long periods of time, as the ionosphere changes in response to solar activity.