Our eyes are only sensitive to a very narrow range of the electromagnetic spectrum. Like the dog that can hear sounds we can't, there is a large spectrum of electromagnetic waves we can not see. If we could see at very low frequencies, called VLF, we would be dazzled by electromagnetic emissions such as sferics, tweeks, whistlers, chorus, and many others. These are natural radio waves or emissions coming from such common phenomena as lightning, but there are also VLF emissions that reach the ground that come from ten's of thousands of miles from the Earth. VLF radio emissions are at such low frequencies that they can be received, amplified and turned into sound that we can hear. Each of the natural VLF radio emissions has a very distinctive sound.
