What are infrasonics? (2025 Update)
Educational and Fun Activities
Written by Alexandra Stone
16 September 2024
🕓 10 min
What Are Infrasonics?
Sound is an everyday part of our lives, but there’s a world of sound we cannot hear. Infrasonics refers to sound waves with frequencies lower than 20 Hz, which fall below the human hearing range. While we may not detect these sounds, many animals and natural events produce them, and they have important applications in science, technology, and nature.
At The Science of Sound, we explore the hidden aspects of sound through STEM workshops, after-school clubs, and holiday camps. Learning about infrasonics helps children understand how low-frequency waves shape our world, from animal communication to natural disaster detection.
In this blog, we’ll cover:
✔ The science behind infrasonics
✔ How animals use infrasonics
✔ The real-world applications of infrasonic waves
✔ A fun experiment to explore low-frequency sound
By the end, you’ll discover how infrasonics play a crucial role in nature and technology!
1. The Science of Infrasonics
Infrasonics refers to sound waves with frequencies below 20 Hz, which are too low for human ears to detect. While we cannot hear these waves, they still travel through air, water, and even the Earth, influencing nature and technology.
How Infrasonics Work:
✔ Lower frequency = longer wavelength, allowing waves to travel vast distances without losing strength.
✔ Can penetrate solid objects, making them useful in geological and structural monitoring.
✔ Produced by natural and artificial sources, including earthquakes, volcanoes, and industrial machinery.
Where Infrasonics Occur:
✔ Earthquakes & Volcanic Eruptions – Release low-frequency waves that scientists use to monitor activity.
✔ Tornadoes & Storms – Generate infrasonics that help predict extreme weather.
✔ Human-Made Sources – Factories, explosions, and engines produce infrasonic waves that travel for miles.
Fun Fact:
Some researchers believe infrasonic waves may be linked to ghost sightings, as they can cause feelings of unease!
2. Why Are Infrasonics Important?
Many animals rely on infrasonics to communicate, sense danger, and navigate their environment. Because low-frequency waves travel long distances, they are useful for species that need to communicate over vast areas.
Animals That Use Infrasonics:
✔ Elephants – Use infrasonic rumbles to communicate with their herd across miles.
✔ Whales – Emit low-frequency calls that travel through water, allowing them to stay in contact over great distances.
✔ Giraffes – Suspected to use infrasonics for subtle communication among their groups.
✔ Tigers – Can produce deep growls that stun their prey, giving them an advantage while hunting.
Why Infrasonics Matter in Nature:
✔ Helps animals warn each other of danger.
✔ Allows for long-distance communication in open environments like oceans and savannas.
✔ Plays a role in hunting and survival.
Fun Fact:
Elephants can sense infrasonic vibrations through their feet, detecting distant storms or approaching predators!
Learn more about how sound impacts human and animal life in our blog The Amazing World of Sound: Discover the Secrets of How We Hear!.
3. Can Humans Detect Infrasonics?
Even though humans can’t hear infrasonic waves, we have found incredible ways to use them in science, safety, and technology. Because these waves travel great distances, they are useful in monitoring natural disasters, detecting structural weaknesses, and even military applications.
Where Infrasonics is Used:
✔ Earthquake & Volcano Monitoring – Scientists detect infrasonic waves to predict eruptions and seismic activity, helping save lives.
✔ Weather Prediction – Infrasonic waves from storms, tornadoes, and hurricanes help meteorologists track extreme weather.
✔ Industrial Testing – Factories use infrasonic waves to check for cracks in bridges, buildings, and machinery.
✔ Military & Security – Some defense systems use infrasonics for early threat detection and surveillance.
Fun Fact:
Infrasonic waves were used to study the explosion of a meteor over Russia in 2013, allowing scientists to estimate its size and impact!
4. Fun Ways to Explore Infrasonics
Although humans can’t hear infrasonic waves, we can experience their effects using simple materials. This experiment helps children understand how low-frequency sound waves create vibrations.
Materials Needed:
✔ A large speaker or subwoofer
✔ A bowl of water
✔ A low-frequency sound file (10-20 Hz)
Steps:
- Place the bowl of water near the speaker.
- Play a low-frequency sound file (many can be found online or generated using tone apps).
- Watch the water’s surface—if the sound is low enough, you should see small ripples or waves forming!
Why This Works:
✔ Infrasonic waves create strong vibrations, which travel through the air and disturb the water’s surface.
✔ This mimics how animals detect distant storms using infrasonics.
For more ideas on fun sound-related activities, check out How Sound Waves Can Be Fun for Primary School Children, where we cover creative ways to teach sound science at home.
Final Thoughts
Even though humans can’t hear infrasonics, these low-frequency waves play a vital role in nature, technology, and science. From animal communication to disaster monitoring, infrasonics helps shape the world around us.
Key Takeaways:
✔ Infrasonics = sound waves below 20 Hz, too low for human hearing.
✔ Used by animals like elephants and whales to communicate over long distances.
✔ Helps scientists monitor earthquakes, volcanoes, and extreme weather.
✔ Plays a role in security, industrial testing, and even ghost-hunting theories!
At The Science of Sound, we help children discover the hidden world of sound through STEM workshops, after-school clubs, and holiday camps, making learning about infrasonics fun and interactive!
