Hisss....

well, I've heard about the hum of the Big Bang...

But now we are told that Earth hisses....


A cosmic "chorus" is filling the skies with a mysterious, low frequency "hiss," according to a May 2009 study. The hiss comes from an electromagnetic wave in Earth's radiation belts, loops of charged particles that get trapped by Earth's magnetic field (pictured).

According to the new data, the hiss wave evolves from a more distant radio wave called chorus, so named because its discoverers thought it sounded like a rookery of birds heard from a distance.

Image courtesy NASA/Goddard Space Flight Center