VIDEO: No One Can Explain These Strange Sounds from All Over the World

Have you ever heard a weird sound that only you could hear? Or something that went on for a couple of seconds and everyone seemed to hear it but no one had an explanation for it?

Don’t worry, you are not going crazy, there are a lot of people who have heard them. We hope to get to see what the logical explanation for them is, but until then all we have are theories, some that seem legit and some that just seem exaggerated.

According to mentalfloss.com, there are a whole lot of weird sounds that people all over the world have heard and that don’t really have an explanation.

Upsweep is an unidentified sound that’s existed at least since the Pacific Marine Environmental Laboratory began recording SOSUS—an underwater sound surveillance system with listening stations around the world—in 1991.

The sound “consists of a long train of narrow-band upsweeping sounds of several seconds duration each.” The source location is difficult to identify, but it’s in the Pacific, around the halfway point between Australia and South America.

Upsweep changes with the seasons, becoming loudest in spring and autumn, though it isn’t clear why. The leading theory is that it’s related to volcanic activity.

The Whistle was recorded on July 7, 1997, and only one hydrophone—the underwater microphones used by the National Oceanic and Atmospheric Administration (NOAA)—picked it up. The location is unknown and limited information has made it difficult to speculate on the source.

Bloop is the big kahuna in unexplained sounds. In 1997, an extremely powerful, ultra-low-frequency sound was detected at various listening stations thousands of miles apart and traced to somewhere west of the southern tip of South America.

The sound only lasted about a minute and and was heard repeatedly over the summer, but not since. Bloop is generally believed to be the sound of a massive icequake, but scientists haven’t totally ruled out the possibility that the sound originated from something “organic.”

Julia was recorded on March 1, 1999, lasted for roughly 15 seconds, and was loud enough to be heard by the entire Equatorial Pacific Ocean hydrophone array. An Antarctic iceberg run aground is the leading suspect for its source.

Slow Down was first recorded on May 19, 1997 and is also credited to an iceberg running aground, though some people insist it might be a giant squid. The sound, lasting about 7 minutes, gradually decreases in frequency, hence the name “slow down.” Like Upsweep, the sound has been heard periodically since it was initially detected.

The Hum has been recorded on several occasions, mostly during the last 50 years or so. In these cases, there have been reports of a relentless and troubling low-frequency humming noise that can only heard by a certain portion of the population.

It’s difficult to pinpoint when instances of the Hum began, but it’s been well-documented since the 1970s, and since then, cases have popped up all over the world—from Ontario, Canada to Taos, New Mexico to Bristol, England to Largs, Scotland and Auckland, New Zealand.

In most instances, the affected group only makes up around two percent of the population, but for those individuals, the Hum is largely inescapable and impossible to track.

Those affected report never having heard noises before, and say the Hum is generally heard indoors and becomes louder at night. It’s also most common in rural and suburban areas and among people between age 55 and 70.