The Earth's Hum
In recent months, there has been a significant increase in video footage shared on YouTube from all around the world capturing mysterious sounds — a kind of "hum" or rumbling, whose origin remains unknown. In English, this phenomenon is referred to as "The Hum", so we’ll stick with that term.
The Hum is a mysterious sound that people regularly report hearing in certain regions, although random occurrences have been recorded across the globe. It's estimated that between 2% and 10% of the population is affected by this phenomenon. The first historically recorded area to experience The Hum was the United Kingdom, back in the early 1970s. In 1990, the Hum began appearing in the United States, with the highest number of reports coming from areas around Taos, New Mexico and the town of Kokomo, Indiana. The source of this humming was never discovered. In most cases, it’s not just a hum — many people also report headaches, nausea, or ear pain.
In 1992, U.S. media reported that the previously peaceful town of Taos in New Mexico had suddenly begun to experience disturbing humming and vibrations, which were only perceived by about half of the population. Later tests revealed that those affected identified the hum as being between 40 and 80 Hz. As is often the case, many conspiracy theories soon emerged — some connected the sounds with the apocalyptic year of 2012, others suggested the existence of a civilization inside the Earth, while some were convinced it was all a hoax. But where does the mysterious hum come from, and why do only certain people hear it? Professor David Deming from the University of Oklahoma tried to answer these questions.
1. Self-Deception
One possibility is that the Hum is simply a product of the mind. Someone writes to a local newspaper or news channel saying they hear strange noises, and within days, the newsroom is flooded with similar testimonies. All could be the result of suggestion. Human history is full of "mass self-deception." The best-known cases are documented in Charles Mackay’s 1841 book Memoirs of Extraordinary Popular Delusions and the Madness of Crowds. The witch hunts, during which around 4 million people were burned in Europe before 1893, are a prime example of such mass delusion.
2. Mistaken Sources
Most people in developed countries live in cities filled with countless sources of low-frequency noise: industrial machines, HVAC systems, boilers, compressors, electrical transformers, traffic, ventilation systems, trains, airplanes, etc. In one case in Kokomo, an acoustic specialist traced the hum to the fan of a nearby cooling system. However, this doesn’t explain every case. As Professor Deming says, "The human mind is designed to find answers. Everyone eventually develops their own theory to believe in, whether it's true or not."
3. The Hum Might Not Be a Sound
There are clues suggesting that the hum might not be an acoustic sound at all, based on the simple fact that only some people can hear it. In Taos, ultra-sensitive low-frequency sound detectors were used — but they recorded nothing. If the hum came from industrial sources, these devices would’ve picked it up.
If the hum isn’t acoustic, it’s likely to be an electromagnetic signal that some sensitive individuals interpret as sound. In the 1940s, the first people who "heard" radar signals were considered mentally ill. But Allan Frey’s 1962 research showed that certain people truly can hear radio waves under specific conditions.
4. Mobile Phones
Interestingly, reports of the hum in the U.S. began to rise as mobile phones became more widespread. Between 1985 and 2001, the number of mobile phones in the U.S. grew from 500,000 to 120 million. Mobile phones operate in the 800–900 MHz range, the same as the frequencies used in Frey’s experiments.
However, this theory has its flaws. Reports from the UK go back to the 1970s, well before the era of mobile phones. Moreover, if the hum were caused by signal towers, it should be louder in areas with more towers — yet no towers are found near Taos or Kokomo.
5. LORAN
LORAN stands for Long Range Radio Navigation — a network of powerful radio transmitters that broadcast at 100 kHz. There are 25 transmitters across the U.S. with outputs between 400–1600 kW. Still, the theory has shortcomings: many people report the hum as intermittent, while LORAN transmits continuously. Also, if Kokomo residents hear it, why don’t people in towns closer to the transmitters?
6. HAARP
Many believe the Hum is linked to HAARP (High-Frequency Active Auroral Research Program). The Earth’s ionosphere, starting at about 70 km altitude, is densely packed with charged ions. While HAARP typically operates in the 2.8–10 MHz range, it can function from 0.001 Hz to 1 GHz. This theory has gained substantial support.
7. TACAMO
TACAMO stands for Take Charge and Move Out — a U.S. military program dating back to 1961. It was designed to allow aircraft to communicate with submarines. The aircraft, like the Lockheed EC-130, use 200 kW transmitters. While the number and locations of these aircraft are classified, there’s strong historical overlap between reported hums and areas where TACAMO aircraft likely operated, especially during the Cold War. Reports peaked between 1960 and 1970, exactly when TACAMO came online.
Final Thoughts
There are still plenty of video and audio recordings of the Hum on the internet. Many may be fakes, but a considerable number appear genuine. Even experts cannot fully explain the phenomenon. And the cases are often eerily similar. So — what’s causing the sounds that people are hearing all around the world? Is it something simple… or is there something more behind it?