Have you ever heard a strange hum that seems to come from nowhere? Well, it turns out that the Earth is actually humming all the time, even if we can’t hear it! Let’s dive into this mysterious phenomenon and find out what’s going on.
Back in the 1970s, people in Bristol, England, started hearing a weird hum. Some thought it was just in their heads, but others said it gave them headaches and nosebleeds. The noise was blamed on local factories, but not everyone was convinced.
In 1991, a similar hum was heard in Taos, New Mexico, and it caught a lot of attention. People from other cities around the world have also reported hearing this hum. Interestingly, only about 2% of people can hear it. Some say it sounds like a constant hum, while others describe it as a noise like a truck idling far away.
There are many theories about what causes the hum. Some people think it’s a government conspiracy, like in the TV show “The X-Files,” where secret sounds were sent out from a Navy antenna. Others believe it might be related to sea creatures, as similar noises have been traced back to schools of fish near houseboats.
While many officials blame industrial sources like factories, this doesn’t explain why the hum is heard all over the world.
Seismologists, who study the Earth’s movements, noticed strange low-frequency readings in the 1990s. These readings were too low for human ears to hear, ranging from 0.01 to 10 Hz. Some early explanations suggested changes in air pressure, but a study in the journal Nature found that the Earth is always vibrating, even when there are no earthquakes.
Recently, scientists have gotten closer to solving the mystery. A study in the journal Geophysical Research Letters found that ocean waves might be the source of the hum. Using computer models, researchers discovered that giant, slow-moving waves create pressure on the sea floor, causing the Earth to vibrate. These vibrations have a frequency of 13-300 seconds, which is too low for us to hear.
Even though we can’t hear the Earth’s hum, one scientist mentioned that if you sped it up 10,000 times, it would sound like the “white noise” you hear on an old TV set between channels. So, that’s what the Earth sounds like!
Speaking of sounds, have you ever wondered if you can hear anything in space? Check out this cool video where Trace explores that question!
Use a frequency generator app to explore different sound frequencies. Try to identify which frequencies you can hear and which you cannot. This will help you understand why the Earth’s hum is inaudible to most people. Discuss your findings with your classmates.
Work in groups to create a simple model demonstrating how ocean waves can cause vibrations. Use a shallow tray filled with water and gently create waves to observe how they affect objects placed at the bottom. Relate this to how ocean waves might cause the Earth’s hum.
Choose one theory about the cause of the Earth’s hum and research it further. Prepare a short presentation to share with the class, explaining the theory and whether you find it convincing. Be ready to answer questions from your classmates.
Explore your environment by mapping out different sounds you hear in various locations. Note the frequency and source of each sound. Compare your findings with the mysterious hum and discuss how environmental sounds can affect us.
Watch a video about whether sound can be heard in space. After watching, discuss with your classmates how this relates to the Earth’s hum and the concept of sound waves traveling through different mediums.
Sure! Here’s a sanitized version of the transcript:
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Can you hear that? Yeah, me neither. But apparently, the Earth is humming right this very moment! Hey listeners, Julia here for DNews.
In the 1970s, an inexplicable hum plagued thousands of people in Bristol, England. While some brushed it off as nonsense, others claimed it caused headaches and nosebleeds. Eventually, the noise was attributed to local factories, but not everyone was satisfied with this explanation.
In the spring of 1991, a similar low-frequency buzz annoyed residents of Taos, New Mexico, attracting significant media attention. It’s never been fully explained. Other cities around the world have reported hearing the hum. It’s estimated that only 2% of the population can hear it. Some hear a constant hum, while others hear a noise resembling an idling diesel truck in the distance.
Some suggest a government conspiracy, similar to an episode of “The X-Files,” where extremely low-frequency sounds were emitted from a U.S. Navy antenna. Others think it could be related to sea creatures, as similar noises heard by residents living on houseboats were traced back to large schools of fish. While most officials quickly point to industrial sources like factories, this doesn’t always explain the hum, especially when it’s a worldwide phenomenon.
Seismologists, scientists who study the mechanical properties of the Earth, noticed some strange readings in the 1990s. Unexplained low-frequency readings appeared on seismographs, too low for human ears, in the range of 0.01–10 Hz. Early explanations for the noise pointed to variations in atmospheric air pressure. One study published in the journal Nature found that the Earth undergoes constant oscillation. The daily energy of this oscillation is about the same as a magnitude 6.0 earthquake, yet it occurs on days when there are no earthquakes to blame.
Now, science is one step closer to finding an answer. In a recent study published in the journal Geophysical Research Letters, researchers identified one possible source of the noise: ocean waves. They used computer modeling to examine wind and waves and found that the movement of giant, slow-moving waves causes the Earth to constantly vibrate. These giant waves exert enormous pressure on the sea floor, creating seismic waves. These waves could produce vibrations with a frequency of 13-300 seconds, or as long as it takes for them to reach the ocean floor.
The hum is far too low for human ears, but one of the leading scientists of the study mentioned that if you played it at 10,000 times the speed, you could hear “white noise” like an old TV set between channels. So that’s what the Earth sounds like.
Speaking of hearing things, have you ever wondered if you can hear sound in space? Check out this great video where Trace finds the answer.
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This version maintains the essence of the original content while ensuring clarity and appropriateness.
Hum – A low, continuous sound often caused by vibrations – The hum of the Earth’s surface can be detected by sensitive instruments used by scientists.
Earth – The third planet from the Sun, home to all known life – Scientists study the Earth’s layers to understand its structure and history.
Vibrations – Rapid motions back and forth or up and down – Vibrations from earthquakes can travel through the Earth and be detected by seismographs.
Scientists – People who study or have expertise in science – Scientists use various tools to measure changes in the Earth’s climate.
Ocean – A large body of salt water that covers most of the Earth’s surface – The ocean plays a crucial role in regulating the Earth’s climate and weather patterns.
Frequency – The number of times a wave repeats in a given period – The frequency of ocean waves can affect how they impact the shoreline.
Pressure – The force applied perpendicular to the surface of an object per unit area – Atmospheric pressure decreases as you climb higher in the Earth’s atmosphere.
Seismologists – Scientists who study earthquakes and the movements of the Earth’s crust – Seismologists use data from seismographs to locate the epicenter of an earthquake.
Noises – Sounds, especially those that are loud or unpleasant – The noises from volcanic eruptions can be heard miles away and are studied to predict future activity.
Theories – Well-substantiated explanations of some aspect of the natural world – One of the most famous theories in Earth science is the theory of plate tectonics.
