High-altitude ballooning and natural radio events

One of the projects for my Electricity and Magnetism class last fall was to conduct original research using a high-altitude weather balloon. The goal of our group was to record the sound of distant lightning strikes (called atmospherics or 'spherics) and other naturally occurring very-low-frequency (VLF) radio events. See also http://en.wikipedia.org/wiki/Radio_atmospheric

I constructed the receiver, right, and assembled the pod, above. Our balloon made it to about 30,000 feet, about a third of what we had hoped for. We suspect that the strength of our balloon was compromised due to its coming into contact with skin oils during the launch. Although nitrile gloves are worn by the launch crew as a precaution, it was extremely windy and the balloon was bonking everybody's heads.

Still, our experiment pod was a success and we recorded about an hour's worth of 'spherics. I processed all our data using Native Instruments' Reaktor, a graphical programming language normally used to design software synthesizers. I was able to abuse bend the software to my will in order to filter out unwanted noise and to measure the amount and strength of 'spheric activity in one-minute intervals. More detail on our experiment can be viewed at the Whitworth Near Space Wiki.