nivek
As Above So Below
Mystery 'hum' that has baffled people around the world for decades is recorded in the ocean for the first time - but scientists still can't explain what it is
A strange hum that has baffled people all over the world for decades has been recorded in the ocean for the first time.
The low frequency hum has been known about for nearly half a century- but its source remains a mystery.
Scientists claim the sound is inaudible to humans, but thousands of people still insist they have heard it.
A website, called ‘The Hum’, has reports about the noise dating back as far as the 1960s.
Theories about what causes it range from mating fish, a secret project to tunnel under the Earth and the presence of aliens.
Now, by measuring the sound using underwater seismometers positioned across the globe, scientists may be able to finally figure out what it.
It's not clear what's causing the hum, but scientists say it may be the result of tiny vibrations in the Earth called 'free oscillations' that can only be picked up by sensitive equipment.
The vibrations are triggered by constant minuscule expansions and contractions of our planet constantly, though scientists still don't understand their source.
Earthquakes have been known to cause the Earth to emit similar vibrations for extended periods, but the hum only occurs in the absence of seismic activity.
The first attempt to detect this hum was made in 1959, but it wasn't until 1998 that scientists had conclusive proof it exists.
The study
The team studied 11 months worth of observations from 57 seismometer stations on the seafloor in the Indian Ocean east of Madagascar.
They picked the two stations with the highest quality readings and painstakingly removed any interference from the data.
By cross-referencing what was left with measurements from terrestrial stations, the team realised the signal that remained was the hum.
The researchers found the noise is almost 10,000 times below the 20 hertz threshold of human hearing.
A strange hum that has baffled people all over the world for decades has been recorded in the ocean for the first time.
The low frequency hum has been known about for nearly half a century- but its source remains a mystery.
Scientists claim the sound is inaudible to humans, but thousands of people still insist they have heard it.
A website, called ‘The Hum’, has reports about the noise dating back as far as the 1960s.
Theories about what causes it range from mating fish, a secret project to tunnel under the Earth and the presence of aliens.
Now, by measuring the sound using underwater seismometers positioned across the globe, scientists may be able to finally figure out what it.
It's not clear what's causing the hum, but scientists say it may be the result of tiny vibrations in the Earth called 'free oscillations' that can only be picked up by sensitive equipment.
The vibrations are triggered by constant minuscule expansions and contractions of our planet constantly, though scientists still don't understand their source.
Earthquakes have been known to cause the Earth to emit similar vibrations for extended periods, but the hum only occurs in the absence of seismic activity.
The first attempt to detect this hum was made in 1959, but it wasn't until 1998 that scientists had conclusive proof it exists.
The study
The team studied 11 months worth of observations from 57 seismometer stations on the seafloor in the Indian Ocean east of Madagascar.
They picked the two stations with the highest quality readings and painstakingly removed any interference from the data.
By cross-referencing what was left with measurements from terrestrial stations, the team realised the signal that remained was the hum.
The researchers found the noise is almost 10,000 times below the 20 hertz threshold of human hearing.
