What the Devastating Japanese Earthquake Sounded Like

At magnitude 9.0, the March 11 earthquake in Japan was the largest recorded in the country's history, causing untold damage, numerous deaths, and a devastating tsunami. In the end, the quake was surely felt -- but what exactly did it sound like?

Researchers at the National Ocean and Atmospheric Administration's (NOAA) Vent Program have released a video that exemplifies the immense power of the earthquake from an auditory perspective.

The recording from the agency's hydrophone, or underwater microphone, documents what an underwater microphone set up in Alaska was able to pick up from the huge quake -- nine hundred miles away.

The initial burst of noise is the P-wave, which stands for 'primary' wave, and the second noise is the sound of the T-wave, or tertiary wave, explained London paper The Daily Mail. Tertiary waves are created when an earthquake occurs under the sea. They are the slowest waves of the three types and are created when their seismic energy goes upward into the ocean.

Listen to the sound of destruction in the YouTube clip NOAA has released, embedded below.

The release of the rumbling audio file came as a pair of robots explored buildings inside Japan's crippled nuclear reactor and returned with with disheartening news: Radiation levels are far too high for repair crews to go inside.

Nevertheless, officials remained hopeful they can stick to their freshly minted "roadmap" for cleaning up the radiation leak and stabilizing the Fukushima Dai-ichi plant by year's end so they can begin returning tens of thousands of evacuees to their homes.

The damage to the plant -- sometimes referred to as a partial meltdown -- had already been widely assumed, but the confirmation, along with the continued release of radiation from other areas, serves to underscore how difficult and how long the cleanup process will be. In fact, government officials themselves have acknowledged that there are still many setbacks that could crop up to slow down their timeline.