MnGCA

[KC0GRN]

I looked them up too, an it's looking like an ancient civilization kinda thing, not really a natural phenomenon either, nor having much to do with radio interference, unless you count superstition.

Oh well, woulda been interesting to use if such a thing existed to throw off radio reception, but guess the only interference we got id the human made stuff, or trees and rocks. That and the occasional solar flare.