Mystery of 'weird hum' heard around the world solved

If you've spent time in the "Weird News" section of your favorite news outlet, you may have encountered the mysterious phenomenon known as "the Hum." According to the The Guardian, the strange occurrence is an odd, low-pitched sound that an estimated four percent of all people are able to hear. Some describe it as "an endless riff of heavy metal music ... difficult to say if felt or heard." Others say it's like "mechanical whirring." Oh, and variations of it have been heard all around the world, from countryside United Kingdom to an island off Alaska to a high-rise building in Australia. Some of the more famous Hums, such as Mexico's Taos Hum and the UK's Suffolk Noise, have reputations of their own. In some cases, we have even been able to identify the source — for instance, a version of the Hum in Windsor, Canada was caused by a blast furnace of a nearby steel plant. 

Reportedly, there's even an unexplainable "Worldwide Hum" that isn't tied to a single area and can't be so easily explained. Whether you believe that or not, science does in fact know about at least one occurrence of a strange, global "hum" event, though it was one that couldn't really be heard by human ears. Oh, and as Live Science tells us, we totally know what caused that one. Buckle up, champ, because things are about to get double weird!

The 'weird hum' heard around the world is an equally strange seismic event

This particular version of the Hum started in May 2018, when literal thousands of small earthquakes were detected off the coast of Mayotte, an island near Madagascar in the Indian Ocean. This Hum wasn't audible by human ears, but it had a strange, machine-like quality: It was "like a fine-tuned bell," ringing at a single ultra-low frequency. Oh, and this ultra-low hum then circled the entire planet, which would have been bad news if it wasn't for the fact that apart from Mayotte, it went entirely without causing the usual effects that come with seismic events (read: earthquakes).  

As this barely perceptible ninja hum-wave made its way around the world, a bunch of scientists got curious about its frankly absurd nature, and started tracking down its root cause. What they found was somehow even weirder than a global stealth earthquake: A stealth volcano. A giant, 3.1 miles long and nearly a half a mile high underwater volcano had formed near Mayotte, and it appears that all those global seismic hums were merely the "rumblings" its magma reservoirs made as they crept from deep under the ocean floor to their new destination.