text: Scientists rumble Earth #39;s hum Scientists have solved the mystery of a global hum which has plagued them since it was discovered in 1998. The constant drone at low frequencies, well below the range of human hearing, shows up in seismic 
inputs: Scientists rumble Earth #39;s hum Scientists have solved the mystery of a global hum which has plagued them since it was discovered in 1998. The constant drone at low frequencies, well below the range of human hearing, shows up in seismic 