10 Sounds That Can’t Be Scientifically Explained

There are thousands of mysteries across the globe that have yet to be explained, but did you know that some of them deal with sounds? Scientists have struggled to explain certain sounds and noises that have occurred around the world. Some of these noises have been repeating over time, while others only happened once. Some sounds are recent, while others date back hundreds of years. Here are a few of those sounds that scientists can’t seem to explain.

Related: Top 10 Strange and Eerie Mysteries in Ireland

10 Bloop

In 1997, a strange ultra-low-frequency sound was detected at various listening stations that were thousands of miles away from each other. The U.S. National Oceanic and Atmospheric Administration (NOAA) detected the sound known as the Bloop and described it as being generated by non-tectonic cryoseisms, also known as ice quakes, originating from glacial movements. The source of the sound started at the southern tip of South America, but the sound reached a higher frequency within a minute and was heard by several sound sensors.

The NOAA believes the most likely cause of the sound was due to ice quakes, but the Bloop has been described to resemble that of a living creature. The rapid variation in frequency is like sounds created by marine beasts. The fact that makes this claim unbelievable is that the Bloop would have been much louder than any whale noise or noise from any other animal ever recorded. If the rumor that some marine animal created the Bloop is true, it would mean a massive unknown beast is lurking in the ocean waters.^[1]

9 Julia

The NOAA recorded another strange sound on March 1, 1999. The sound recorded is known as Julia, and it was believed to most likely be caused by a large iceberg from Antarctica. The noise resembled someone cooing and was heard across the entire Equatorial Pacific Ocean autonomous hydrophone array. Due to much uncertainty, the point of origin was only narrowed down to somewhere between Cape Adare and the Bransfield Straits. With the sound occurring only two years after the Bloop, was Julia another monster hiding in the depths of the sea?^[2]

8 Colossi of Memnon

Located in Luxor, Egypt, two gigantic stone statues of Pharaoh Amenhotep III stand, known as the Colossi of Memnon. In 27 BC, the statues were damaged in a large earthquake. Part of one of the statues was shattered, and the top half fell onto the lower half, creating a fissure in the statue. People in the area soon started to hear a strange noise coming from the statue at dawn. According to the Greek historian and geographer Strabo, the noise sounded like singing.

Around AD 199, the earthquake damage was ordered to be repaired by the Roman emperor Septimius Severus. The statues still stand today, but the sounds have not been heard since those repairs were made. Scientists believe that a rise in heat and humidity of the ruins helped cause the sound. Their theory suggests that the increase in temperature at dawn caused the dew inside the porous rock to evaporate and cause a singing sound, but the true explanation for the sound may never be known.^[3]

7 The Whistle

The NOAA recorded another sound in 1997, known as the Whistle. The sound was recorded by the Eastern Pacific autonomous hydrophone on July 7. Several noises sounding like the Whistle were recorded previously, but they were volcanic signals from the Mariana volcanic arc. The Whistle was similar to volcanogenic signals of active erupting submarine arc volcanoes, but the location could not be determined.

To locate the source of an event, at least three recording instruments must pick up the sound. The Whistle noise was only recorded by the northwest hydrophone, but it could have traveled a long distance from its source before being detected. The source is still unknown to this day.^[4]

6 The Hum

There has been a strange sound disturbing people in several places around the world for the last 60 years. Around 2% of the world’s population is estimated to hear it, with cases popping up in places like New Mexico, Canada, England, Scotland, and New Zealand. The mysterious sound, known as the Hum, sounds like a vehicle idling, and it tends to keep people up at night. The noise may not be a physical sound, though, as some believe that the sound may just come from people focusing too much on ambient noise.

Many who have heard the sound say it is mostly heard indoors and becomes louder at night. Theories have tried to pinpoint the noise, suggesting it could be coming from wireless communication towers, tunneling under the earth, electromagnetic radiation, power and gas lines, radio waves, and even alien communications. The sound appears and disappears so frequently that it is hard for any group to pinpoint the origin. The story may sound like it comes straight out of a horror movie, but the reality is that the sound is still a mystery waiting to be uncovered.^[5]

5 Upsweep

The ’90s proved to be a weird and busy time for the NOAA. In 1991, they detected a scary sound in the Pacific Ocean using the hydrophones known as the Upsweep. The Upsweep is composed of a long train of sounds that moves repeatedly upward from a low to high frequency. The sound changes with the seasons and becomes loudest in spring and autumn. The reason for the change isn’t exactly known, but it is most likely caused by the changes in the environment the sound travels through.

The explanation for Upsweep is still unconfirmed by scientists, but the plausible explanation would be undersea volcanoes. The undersea volcanic activity may be causing hot lava to pour into the cold seawater. The Upsweep is still being detected today, but the level of the noise has drastically declined since its discovery.^[6]

4 Slow Down

Slow Down is another noise that was first discovered in 1997, and like Upsweep, it can still periodically be heard today. The Slow Down was recorded on the Equatorial Pacific Ocean autonomous hydrophone array, and it was given the name due to the sound slowly descending in frequency over seven minutes. The NOAA said the noise was of sufficient amplitude to be heard on three different sensors at a range of nearly 2,000 km, and that type of signal had never been heard, nor has it since.

The sound is likely credited to an iceberg running aground, but there have been several theories thrown around, including that of a large giant squid making the noise. The origin of the sound is still unknown, but the general location is somewhere off the west coast of South America.^[7]

3 UVB-76

UVB-76, also known as the Buzzer, is a short-wave radio station that broadcasts in Russia. It is not the sound coming from UVB-76 that can’t be explained, but the purpose behind the sound is what remains a mystery. UVB-76 broadcasts a short buzz tone that repeats itself several times a day. The signal has also been interrupted in the past, and other sounds, words, names, and numbers can be heard. In 2010, the station changed location after a storm, and groups of explorers triangulated the old location to a remote Russian town home to a military base.

A small book was found on the military base that contained a log of messages sent by UVB-76, which helped confirm that the signal had been run by the Russian military. Messages were still being emitted after the old location was found, but the new location was a mystery. UVB-76 was coming from multiple transmitters across the country, making it hard to triangulate a possible location.

The purpose of these strange buzzes, beeps, and words is the real mystery, though. Some theories point to ownership of the signal belonging to the Russian government, and they are keeping it in play in case of nuclear war or any other war that could cause a loss of communications.^[8]

2 52-Hertz Whale

The frequency of a blue whale call usually ranges somewhere between 10 Hz and 39 Hz, and fin whale calls have a frequency of 20 Hz. However, a short frequency call of a whale of unidentified species came in at a whopping 52 Hz. In 1992, The sound was tracked by navy hydrophones in the North Pacific, and it is believed to have come from an animal that could be a hybrid of a blue whale and a fin whale.

The whale has been described as the “world’s loneliest whale,” but there have been potential recordings of a similar 52-hertz whale heard at the same time in another location. Even though the song of this unidentified whale differs from that of other whales, the other whales can hear it and probably even respond to it. The 52-hertz whale has also been mentioned in several movies, books, and songs.^[9]

1 Skyquakes

Imagine the sound of thunder on steroids—that is what some have been hearing for nearly 200 years. The loud noise has been reported all across the globe in places such as Italy, Australia, and the United States. However, it generally happens near large bodies of water. Since the mysterious noise occurs near water, the sound could be coming from large waves crashing against cliffs or gas rising from underground vents at the bottom of the ocean.

Other causes that scientists have come up with include rare noises from sand dunes, meteors entering the earth’s atmosphere, shock waves caused by the sun crashing into the earth’s magnetic field, volcanic eruptions, and distant thunder. The more logical reason for recent skyquakes is military aircraft breaking the sound barrier, but that would still leave a mystery for the noises that occurred in the 1800s.^[10]