Hear it again: Discovering the mysteries rumbling beneath our feet

Seismographs pick up rumblings from sources other than earthquakes all the time.

In those cases, scientists have to become detectives to track down just what created those "exotic events."

Last year, Soundside spoke with Steve Malone from the Pacific Northwest Seismic Network about just what these "exotic events" are. From glacial jolts to sonic booms, space debris to local climbers, chasing those sources is a hobby as much as it is a science for Malone.

You can listen to the full segment by clicking the "play" button on the audio above.

Find the original story here.