Although they’re emitted by some in the animal world, infrasound are sound waves with frequencies so low, they are beyond the limit of human hearing.
Now, thanks to the app call RedVox, scientists and even you can gain a better understanding of infrasound. The low-frequency sounds are usually caused by the movement, vibration, or explosion of large things or fast objects.
“We started exploring all these different deep sounds because at the time a lot of these very expensive instruments are emerging there were very few of us that could get the resources from the instrumentation to get measurements,” Milton Garces, University of Hawaii Hilo researcher, said.
Garces is with the University of Hawaii’s School of Earth Science and Technology (SOEST).
He says the app they developed initially helped with the early detection of natural events such as hurricanes, volcanic explosions, and even meteors. Now he says the app can can be used to detect rocket and missile launches anywhere in the world.
Just this morning, it immediately picked up the rocket launch from Florida that was carrying supplies to the International Space Station.
But Farces says it can also detect hostile missile launches.
While the government already has a multi-billion dollar detection system in place, Garces says it’s not without faults.
“At some point we realized we need something that’s easier and more accessible so we built this app because smartphone technology got to the point where we could. 10 years ago this was not possible,” Garces explained.
Garces says cell phones will fill the coverage gaps any government sponsored system will have.
“And so this is a method to engage people in measuring things and recording things that are impacting them as individuals, individual states, and cities. This is the whole citizen scientist movement,” Garces explained.
In order for the app to work, the user must allow access to both the location feature as well as the built in microphone. This raises the question, who’s listening to what?
Garces says the app is designed to adhere to strict U.S. State Department policy on privacy. Ultimately, the user has total control.
“Only you can enable the app to record, and only you can allow a change of location,” Garces said.
If you want to check it out the app is called RedVox and it’s free.
Garces says the next step is to make it more understandable for non-scientists.
What is Infrasound?
Infrasound is bass sound below the human hearing range. When sudden and intense – as when a door slams – it may be perceived as a startling, palpable sensation . Infrasound can be excited by the movement, vibration or explosion of large things, or by fast objects. Big vibrating sources include the oceans, earthquakes, tsunamis, bad weather, and power generation systems. Explosive things include volcanoes, breaking waves, quarry blasts, and nuclear tests. Fast things include jets, departing and arriving spacecraft, and meteors.
As an example of a big, fast thing blowing up, infrasound from the 2013 Chelyabinsk meteor over Russia propagated around the world at least twice, and had an equivalent yield of a 1 Megaton nuclear bomb. Anybody with a cell phone within a thousand miles could have picked up this signal.
Recording infrasound used to be complicated and expensive. With the RedVox infrasound apps, anybody can now explore the inaudible sound field around them, and help build a global hazards and noise monitoring network.
The Infrasound Recorder enables your iPod Touch, iPad, and iPhone to capture subaural sundscapes. The Infrasound Analyzer permits on-board processing of the data you collected with the Recorder. The next sections provide more detains on How to RedVox.