Try to close your eyes and open your ears, listen to your surrounding and describe it. Is it glaring horn and cars passing by? Then move to quieter places, maybe the park nearby, can you hear the wind blowing gently rustling the leaves?

Well, maybe you often experience that, but beneath the sounds, there’s actually quieter whisper you never listened, it is the earth that’s humming. Seismic movement produces a permanent low frequency vibration that’s too low to be heard without any special equipment.

The Song Of The Earth

This is like an earthquake but far smaller than the catastrophe. We cannot feel it because it is too small to be felt too. Since 1990, actually scientists have known that the earth is constantly humming, known as free oscillation. But they cannot do further research because in that time, the equipment is still low.

Scientists recently have recorded the hum of the earth from the ocean floor. Using special ocean seismometers, scientists traveled to sea floor in Indian Ocean to record the low frequency sound. And after 11 months of work, they finally could capture the sound.

After filtering out louder noises like ocean wave and seafloor currents, scientists found a consistent peak. The peak appeared in several frequencies between 2.9 to 4.5 millihertz. The sound is about 10,000 times lower than our hearing threshold which is 20 hertz.

The result of this study is an opening to further studies about the interior of this earth. By measuring the sound, scientist will be able to collect some data needed in future researches.  And now, the humming of the earth is no longer a mysterious sound.

Beside that hum, there are also other natural sounds produced by natural occurrences that people all around the world can hear. Some of them are mysterious, and some others are unpredictable. Which one is the song of mother nature? Here is the list inspired by a post in Live Science.

1. The Bloop

For more than 70 years, people have tried to listen to the ocean. Both scientists and military forces have put some effort by sending in listening devices. From that effort many underwater sounds recorded and most of them are ordinary underwater events.

But there is one mysterious sound recorded in 1997 by US National Oceanic and Atmospheric Administration (NOAA) called The Bloop. The Bloop is a loud noise, much louder than noises any animal can make, that can last up to a minute long.

The sound is so loud that it can be heard from microphone located five thousand kilometers away. NOAA suggest that the sound comes from the splitting of icebergs in Antarctica and fall into the ocean, but no official research has been able to prove where does the sound come from.

2. Another Hum

Unlike the hum produced by the earth, this kind of hum is audible and can be heard by people all around the world. It is still a mystery whether this hum is a kind of social phenomenon or natural occurrence, but many conspiracy theorists believe that this hum is made either by government or alien.

This phenomenon often occurs in United Kingdom and United States. Many people have reported to hear low-pitched humming sound like the sound of idling engine or electrical devices. But apparently there are no such engine operating near the place, and that’s what making it mysterious.

Some people reportedly hear this kind of hum more often and this hum is often linked to only several areas on earth. The most famous ones are Taos Hum in New Mexico and Bristol Hum in England. Up until now, this phenomenon is still mysterious.

3. Rainbow Bridge Rock Guitar

 

If mother nature can sing, what kind of music would be her favorite? Folk or pop? What if it is rock? The famous rainbow bridge from Utah, aside of being famous as a place to stargaze, also famously known to play “rock guitar” sounds.

When stimulated by other sounds and vibrations, the 90 meters high arch of rock can imitate the sound of plucked guitar string. By making precise measurements of the vibrations, researchers are able to identify some sources of vibrations that cause the guitar sound in the arch.

The stimulation can be various, such as waves of nearby lake, earthquakes, and other kind of vibrations. Researchers are now learning about the rainbow bridge vibration to know better about the stability of the geological structure and to learn how to preserve the iconic sandstone arch.

4. The Sound Of Aurora

 

Aurora, not only famous of being one of the most beautiful phenomenon on earth for our eyes, also produces a beautiful ephemeral sound for our ears to hear. Many people have witnessed the sound of aurora when the phenomenon appeared at its most powerful state.

The sound of aurora is described as faint sizzling, popping, and crackling. Researchers were trying to record the sound more clearly using satellites floating hundreds of kilometers above the surface of earth.

An acoustician from Finland, Unto Laine, is the first one to be able to keep the sound in a recording device. According to Laine, the sound is maybe produced by regions of electrical charge building up in the atmosphere.

When the electrical charged atmosphere layer disturbed by magnetic storms from the sun, which creates the aurora, they create a small park in the atmosphere. Laine suggested that’s the source of the sound of aurora.

5. Under The Sea Choir

 

Do you know that fish can actually sing? No, we are not talking about the choir in Disney’s movie Little Mermaid, but this is real fact. Apparently, sound plays an important part in many fish behavior, including breeding, feeding, and territorial disputes.

Australian researchers from Curtin University found out that in dawn and dusk many species of fish join in a mass chorus in the same way as birds do. The researchers were also able to record the sounds the fish produced and created an orchestra from it.

So, from natural sounds listed above, which one do you think is the song Mother Nature sings?