Earth’s Ringing: Vibrations of the Entire Planet

After a massive earthquake, Earth itself can vibrate like a struck bell.
These global vibrations are called the planet’s free oscillations.
They can last for days or even weeks after a giant quake.
Seismographs around the world pick up Earth’s ringing as repeating wave patterns.
Different oscillation modes make Earth “hum” at multiple natural frequencies.
The strongest ringing events come from magnitude 8.5+ earthquakes.
Earth’s ringing helps scientists study the planet’s inner structure, much like ultrasound images in medicine.
Even without quakes, Earth produces a faint background hum from ocean waves and atmospheric forces.
These vibrations are far below human hearing, in the range of infrasound.
Earth’s ringing is a reminder that our planet is not static but a dynamic, vibrating world.