sound travel water

How far does sound travel in the ocean?

The distance that sound travels in the ocean varies greatly, depending primarily upon water temperature and pressure..

Water temperature and pressure determine how far sound travels in the ocean.

While sound moves at a much faster speed in the water than in air , the distance that sound waves travel is primarily dependent upon ocean temperature and pressure. While pressure continues to increase as ocean depth increases, the temperature of the ocean only decreases up to a certain point, after which it remains relatively stable. These factors have a curious effect on how (and how far) sound waves travel.

Imagine a whale is swimming through the ocean and calls out to its pod. The whale produces sound waves that move like ripples in the water. As the whale’s sound waves travel through the water, their speed decreases with increasing depth (as the temperature drops), causing the sound waves to refract downward . Once the sound waves reach the bottom of what is known as the thermocline layer, the speed of sound reaches its minimum. The thermocline is a region characterized by rapid change in temperature and pressure which occurs at different depths around the world. Below the thermocline "layer," the temperature remains constant, but pressure continues to increase. This causes the speed of sound to increase and makes the sound waves refract upward .  

The area in the ocean where sound waves refract up and down is known as the "sound channel." The channeling of sound waves allows sound to travel thousands of miles without the signal losing considerable energy.  In fact, hydrophones, or underwater microphones, if placed at the proper depth, can pick up whale songs and manmade noises from many kilometers away.

Search Our Facts

More information.

• Noise in the Ocean: A National Issue (National Marine Sanctuaries)
• Just how noisy is the ocean? Learn about a NOAA Effort to Monitor Underwater Sound
• Sound in the Sea Gallery
• Acoustic Monitoring

Last updated: 06/16/24 Author: NOAA How to cite this article

• Subscribe to BBC Science Focus Magazine
• Previous Issues
• Future tech
• Everyday science
• Planet Earth
• Newsletters

© Getty Images

How fast does sound travel through water?

Sounds travel faster through water than in air, but it takes more energy to get it going.

Sound is a wave of alternating compression and expansion, so its speed depends on how fast it bounces back from each compression – the less compressible the medium it’s travelling through, the faster it bounces back. Water is about 15,000 times less compressible than air, but it is also 800 times denser. The extra density means that the molecules accelerate more slowly for a given force, which slows the compression wave down. So water’s high density partly offsets its extreme incompressibility and sound travels at 1,493m/s, about four times faster than through air. The speed of sound in diamond is so high because it is extremely incompressible and yet relatively light.

Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.

Share this article

• Terms & Conditions
• Privacy policy
• Cookies policy
• Code of conduct
• Magazine subscriptions
• Manage preferences

June 27, 2019

What Do You Hear Underwater?

A submerged science activity from Science Buddies

By Science Buddies & Sabine De Brabandere

Make waves--underwater! Learn how sound travels differently in water than it does in the air. 

George Retseck

Key Concepts Physics Sound Waves Biology

Introduction Have you ever listened to noises underwater? Sound travels differently in the water than it does in the air. To learn more, try making your own underwater noises—and listening carefully. 

Background Sound is a wave created by vibrations. These vibrations create areas of more and less densely packed particles. So sound needs a medium to travel, such as air, water—or even solids. 

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing . By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

Sound waves travel faster in denser substances because neighboring particles will more easily bump into one another. Take water, for example. There are about 800 times more particles in a bottle of water than there are in the same bottle filled with air. Thus sound waves travel much faster in water than they do in air. In freshwater at room temperature, for example, sound travels about 4.3 times faster than it does in air at the same temperature.

Sound traveling through air soon becomes less loud as you get farther from the source. This is because the waves’ energy quickly gets lost along the way. Sound keeps its energy longer when traveling through water because the particles can carry the sound waves better. In the ocean, for example, the sound of a humpback whale can travel thousands of miles!

Underwater sound waves reaching us at a faster pace and keeping their intensity longer seem like they should make us perceive those sounds as louder when we are also underwater. The human ear, however, evolved to hear sound in the air and is not as useful when submerged in water. Our head itself is full of tissues that contain water and can transmit sound waves when we are underwater. When this happens, the vibrations bypass the eardrum, the part of the ear that evolved to pick up sound waves in the air. 

Sound also interacts with boundaries between two different mediums, such as the surface of water. This boundary between water and air, for example, reflects almost all sounds back into the water. How will all these dynamics influence how we perceive underwater sounds? Try the activity to find out! 

Bathtub or swimming pool (a very large bucket can work, too)

Two stainless steel utensils (for example, spoons or tongs)

Two plastic utensils

Small ball 

Adult helper

An area that can get wet (if not performing the activity at a pool)

Floor cloth to cleanup spills (if not performing the activity at a pool)

Other materials to make underwater sounds (optional)

Access to a swimming pool (optional)

Internet access (optional)

Preparation

Fill the bathtub with lukewarm water—or head to the pool—and bring your helper and other materials.

Ask your helper to click one stainless steel utensil against another. Listen. How would you describe the sound? 

In a moment, your helper will click one utensil against the other underwater . Do you think you will hear the same sound? 

Ask your helper to click one utensil against the other underwater. Listen. Does the sound appear to be louder or softer? Is what you hear different in other ways, too?

Submerge one ear in the water. Ask your helper to click one utensil against the other underwater. Listen. How would you describe this sound? 

Ask your helper to click one utensil against the other underwater soon after you submerge your head. Take a deep breath, close your eyes and submerge your head completely or as much as you feel comfortable doing. Listen while you hold your breath underwater (come up for air when you need to!). Does the sound appear to be louder or softer? Does it appear to be different in other ways? 

Repeat this sequence but have your helper use two plastic utensils banging against each other instead.

Repeat the sequence again, but this time listen to a small ball being dropped into the water. Does the sound of a ball falling into the water change when you listen above or below water? Does your perception of this sound change? Why would this happen? 

Switch roles. Have your helper listen while you make the sounds. 

Discuss the findings you gathered. Do patterns appear? Can you conclude something about how humans perceive sounds when submerged in water? 

Extra : Test with more types of sounds: soft as well as loud sounds, high- as well as low-pitched sounds. Can you find more patterns?

Extra: To investigate what picks up the sound wave when you are submerged, use your fingers to close your ears or use earbuds when submerging your head. How does the sound change when you close off your ear canal underwater? Does the same happen when you close off your ear canal when you are above water? If not, why would this be different? 

Extra: Go to the swimming pool and listen to the sound of someone jumping into the water. Compare your perception of the sound when you are submerged with when your head is above the water. How does your perception change? Close your eyes. Can you tell where the person jumped into the water when submerged? Can you tell when you have your head above the water?

Extra: Research ocean sounds and how sounds caused by human activity impact aquatic animals.  

Observations and Results Was the sound softer when it was created underwater and you listened above the water? Did it sound muffled when you had only your ear submerged? Was it fuller when you had your head submerged? 

Sound travels faster in water compared with air because water particles are packed in more densely. Thus, the energy the sound waves carry is transported faster. This should make the sound appear louder. You probably perceived it as softer when you were not submerged, however, because the water surface is almost like a mirror for the sound you created. The sound most likely almost completely reflected back into the water as soon as it reached the surface. 

When you submerged only your ear, the sound probably still appeared muffled. This happens because the human ear is not good at picking up sound in water—after all, it evolved to pick up sound in air. 

When you submerged your head, the sound probably sounded fuller. That is because our head contains a lot of water, which allows the tissue to pick up underwater sound—without relying on the eardrum. It also explains why closing your ear canal makes almost no difference in the sound you pick up while you are underwater. 

If you tried to detect where the sound came from when submerged, you probably had a hard time. Our brain uses the difference in loudness and timing of the sound detected by each ear as a clue to infer where the sound came from. Because sound travels faster underwater and because you pick up sound with your entire head when you are submerged, your brain loses the cues that normally help you determine where the sound is coming from. 

More to Explore Discovery of Sound in the Sea , from the University of Rhode Island and the Inner Space Center Can You Hear Sounds in Outer Space? , from Science Buddies Talk through a String Telephone , from Scientific American Sound Localization , from Science Buddies  Ears: Do Their Design, Size and Shape Matter? , from Scientific American STEM Activities for Kids , from Science Buddies 

This activity brought to you in partnership with Science Buddies

The basic components of a sound wave are frequency, wavelength and amplitude. In this example of a sound wave, the period of one cycle of this wave is 0.5 seconds, and the frequency of this wave is 2 cycles per second or 2 Hertz (Hz). Click image for larger view.

Click image to hear a scale of various frequencies (576 K, QuickTime). Click image for larger view.

Understanding Ocean Acoustics

Sharon Nieukirk, Research Assistant Acoustic Monitoring Project NOAA Pacific Marine Environmental Laboratory

What is Sound?

Ocean acoustics is the study of sound and its behavior in the sea. When underwater objects vibrate, they create sound-pressure waves that alternately compress and decompress the water molecules as the sound wave travels through the sea. Sound waves radiate in all directions away from the source like ripples on the surface of a pond. The compressions and decompressions associated with sound waves are detected as changes in pressure by the structures in our ears and most man-made sound receptors such as a hydrophone, or underwater microphone.

The basic components of a sound wave are frequency, wavelength and amplitude.

Frequency is the number of pressure waves that pass by a reference point per unit time and is measured in Hertz (Hz) or cycles per second. To the human ear, an increase in frequency is perceived as a higher pitched sound, while a decrease in frequency is perceived as a lower pitched sound. Humans generally hear sound waves whose frequencies are between 20 and 20,000 Hz. Below 20 Hz, sounds are referred to as infrasonic, and above 20,000 Hz as ultrasonic. The frequency of middle “C” on a piano is 246 Hz.

Wavelength is the distance between two peaks of a sound wave. It is related to frequency because the lower the frequency of the wave, the longer the wavelength.

Amplitude describes the height of the sound pressure wave or the “loudness” of a sound and is often measured using the decibel (dB) scale. Small variations in amplitude (“short” pressure waves) produce weak or quiet sounds, while large variations (“tall” pressure waves) produce strong or loud sounds.

The two examples below show sound waves that vary in frequency and amplitude.

These two waves have the same frequency but different amplitudes. Click image for larger view .

These two waves have the same amplitude but different frequencies. Click image for larger view.

The decibel scale is a logarithmic scale used to measure the amplitude of a sound. If the amplitude of a sound is increased in a series of equal steps, the loudness of the sound will increase in steps which are perceived as successively smaller. A decibel doesn’t really represent a unit of measure like a yard or meter, but instead a pressure value in decibels expresses a ratio between the measured pressure and a reference pressure. On the decibel scale, everything refers to power, which is amplitude squared. And just to confuse things, the reference pressure in air differs from that in water. Therefore a 150 dB sound in water is not the same as a 150 dB sound in air. So when you are describing sound waves and how they behave it is very important to know whether you are describing sound in the sea or in air.

Note on Acoustic Noise Level Units: Hydrophones measure sound pressure, normally expressed in units of micropascals (µPa). Early acousticians working with sound in air, realized that human ears perceive differences in sound on a logarithmic scale, so the convention of using a relative logarithmic scale (dB) was adopted. In order to be useful, the sound levels need to be referenced to some standard pressure at a standard distance. The reference level used in air (20µPa @ 1m) was selected to match human hearing sensitivity. A different reference level is used for underwater sound (1µPa @ 1m). Because of these differences in reference standards, noise levels cited in air do NOT equal underwater levels. To compare noise levels in water to noise levels in air, one must subtract 26 dB from the noise level referenced in water. For example, a supertanker radiating noise at 190 dB (re 1µPa @ 1m) has an equivalent noise level in air of about 128 dB (re 20µPa @ 1m). These numbers are approximate, and amplitude often varies with frequency.

Faster than the Speed of Sound...

The speed of a wave is the rate at which vibrations move through the medium. Sound moves at a faster speed in water (1500 meters/sec) than in air (about 340 meters/sec) because the mechanical properties of water differ from air. Temperature also affects the speed of sound (e.g. sound travels faster in warm water than in cold water) and is very influential in some parts of the ocean. Remember that wavelength and frequency are related because the lower the frequency the longer the wavelength. More specifically, the wavelength of a sound equals the speed of sound in either air or water divided by the frequency of the wave. Therefore, a 20 Hz sound wave is 75 m long in the water (1500/20 = 75) whereas a 20 Hz sound wave in air is only 17 m long (340/20 = 17) in air.

As we descend below the surface of the sea, the speed of sound decreases with decreasing temperature. At the bottom of the thermocline, the speed of sound reaches its minimum; this is also the axis of the sound channel. Below the thermocline the temperature remains constant, but pressure increases which causes the speed of sound to increase again. Sound waves bend, or refract, towards the area of minimum sound speed. Therefore, a sound wave traveling in the sound channel bends up and down and up and down and can travel thousands of meters. Click image for larger view.

The SOFAR Channel

Sound in the sea can often be “trapped” and effectively carried very long distances by the “deep sound channel ” that exists in the ocean. This SOFAR or SOund Fixing And Ranging channel is so named because it was discovered that there was a "channel" in the deep ocean within which the acoustic energy from a small explosive charge (deployed in the water by a downed aviator) could travel over long distances. An array of hydrophones could be used to roughly locate the source of the charge thereby allowing rescue of downed pilots far out to sea. Sound, and especially low-frequency sound, can travel thousands of meters with very little loss of signal. Read more information on the SOFAR channel.

The field of ocean acoustics provides scientists with the tools needed to quantitatively describe sound in the sea. By measuring the frequency, amplitude, location and seasonality of sounds in the sea, a great deal can be learned about our oceanic environment and its inhabitants. Hydroacoustic monitoring (listening to underwater sounds) has allowed scientists to measure global warming, listen to earthquakes and the movement of magma through the sea floor during major volcanic eruptions, and to record low-frequency calls of large whales the world over. As our oceans become more noisy each year, the field of ocean acoustics will grow and only become more essential. For more information and a tutorial on ocean acoustics .

Sign up for the Ocean Explorer E-mail Update List .

E-mail Updates | User Survey | Contact Us | Report Error On This Page | Privacy Policy | Disclaimer | Site Info | Site Index Revised August 26, 2022 by the NOAA Ocean Explorer Webmaster Office of Ocean Exploration and Research | National Oceanic and Atmospheric Administration | U.S. Department of Commerce http://oceanexplorer.noaa.gov/explorations/sound01/background/acoustics/acoustics.html

Internet Explorer lacks support for the features of this website. For the best experience, please use a modern browser such as Chrome, Firefox, or Edge.

Understanding Sound in the Ocean

Levels of underwater noise from human activities—including from ships, sonar, and drilling—have increased dramatically. Those growing levels of ocean noise affect marine animals and habitats in complex ways.

Table of Contents

What types of sounds occur in the ocean, why is sound important to marine animals, does sound behave differently underwater than in air, what kinds of underwater sounds do people produce, how does the sound we produce affect marine species, what is noaa fisheries doing about sound in the ocean, how does noaa fisheries help protect marine life from the harmful impacts of ocean noise.

Both natural and human-made sounds occur in the ocean. Natural sounds come from marine life and naturally occurring events like underwater earthquakes. Human-made sounds come from many sources, such as ships, underwater energy exploration, military sonar, and underwater construction, among others.

Learn more about sound in the ocean .

Sound is essential to many types of marine animals and is one of the main tools they use to survive in the ocean. Light can only penetrate a few hundred feet underwater, but sound can travel much farther. As a result, cetaceans (whales, dolphins, and porpoises) have evolved over millions of years to send and receive a variety of complex sounds. They rely on sound to communicate with each other, navigate, find mates and food, defend their territories and resources, and avoid predators. Fish and invertebrates also use sound for basic life functions.

Because water is denser than air, sound travels faster and farther in the ocean. Its speed and distance depends on the density of the water (determined by its temperature, salinity, and depth) and the frequency of the sound, measured in hertz (Hz). Some sounds, particularly low-frequency ones, can cover vast distances, even across ocean basins.

People produce some sounds intentionally, such as military sonar and seismic tests for oil and gas exploration. Other sounds are an unintentional by-product of an activity, such as shipping and underwater construction. Many human-produced sounds in the ocean are intermittent, whereas shipping creates an almost constant rumble in the ocean. Even the motor of a fishing boat creates extra sound underwater.

All of these sounds add to overall ocean noise and contribute to the “soundscape,” which scientists define as the combined sounds made by humans, natural events, and marine animals. Because sound travels so well underwater, many of these sounds can be heard miles from their sources.

Depending on the sound source, duration, and location, human-caused sound has the potential to affect animals by:

• Causing temporary or permanent hearing loss.
• Causing a stress response.
• Forcing animals to move from their preferred habitat.
• Disrupting feeding, breeding/spawning, nursing, and communication behaviors.

The impacts may be immediate and severe, or they may accumulate over time.

We are engaged on several fronts to better understand and manage ocean sounds, specifically in regard to cetaceans and other types of marine life. Most recently, we published the Ocean Noise Strategy Roadmap which defines a 10-year plan for the agency to address ocean noise.

In 2011, we started the CetSound mapping project . CetSound provides two mapping tools: SoundMap and CetMap . SoundMap allows us to map the time and location of noise, and CetMap shows how many cetaceans are in a given area at a specific time. This information is used to determine where marine animals go to breed and find food, what routes they use to migrate, and where small or fixed populations are concentrated. We then have a better understanding of how ocean noise affects them.

NOAA Fisheries is also part of an interagency partnership that established a set of undersea listening stations around the United States to measure levels of background noise in the ocean.

Among many efforts to protect marine species, NOAA Fisheries administers the Endangered Species Act to recover threatened and endangered species and prevent their extinction. Through consultations under the ESA , we develop biological opinions  to determine how the actions of federal agencies may affect ESA-listed species and critical habitat .

We also are responsible for authorizing the “take” of marine mammals that can result from the sounds produced by human activities. These Incidental Take Authorizations are issued under the Marine Mammal Protection Act . The MMPA limits the numbers of animals that can be “taken” (disturbed or hurt) as a result of human activities and ensures that those activities result in a negligible impact on marine mammal species and stocks.

By knowing how much underwater noise humans produce around the world, scientists can develop ways to reduce or prevent it, as well as ways to protect marine animals from it.

Learn more about sound in the ocean and what NOAA is doing to reduce it to protect marine animals:

• NOAA's Ocean Noise Strategy  
• NOAA Fisheries' Ocean Acoustics Program  

Marine Mammal Acoustic Technical Guidance

How fast does sound travel?

In 1826 on Lake Geneva, Switzerland, Jean-Daniel Colladon, a physicist, and Charles-Francois Sturm, a mathematician, made the first recorded attempt to determine the speed of sound in water. In their experiment, the underwater bell was struck simultaneously with ignition of gunpowder on the first boat. The sound of the bell and flash from the gunpowder were observed 10 miles away on the second boat. The time between the gunpowder flash and the sound reaching the second boat was used to calculate the speed of sound in water. Colladon and Sturm were able to determine the speed of sound in water fairly accurately with this method. Image: J. D. Colladon, Souvenirs et Memoires, Albert-Schuchardt, Geneva, 1893.

We know that sound travels. How fast does it travel? Sound travels about 1500 meters per second in seawater. That’s approximately 15 soccer fields end-to-end in one second. Sound travels much more slowly in air , at about 340 meters per second, only 3 soccer fields a second.

Unfortunately, the answer is really not quite that simple. The speed of sound in seawater is not a constant value. It varies by a small amount (a few percent) from place to place, season to season, morning to evening, and with water depth. Although the variations in the speed of sound are not large, they have important effects on how sound travels in the ocean.

What makes the sound speed change? It is affected by the oceanographic variables of temperature , salinity , and pressure . We can look at the effect of each of these variables on the sound speed by focusing on one spot in the ocean. When oceanographers look at the change of an oceanographic variable with water depth, they call it a profile . Here we will examine the temperature profile, the salinity profile, and the pressure profile. Similar to the profile of your face that gives a side view of your face, an oceanographic profile gives you a side view of the ocean at that location from top to bottom. It looks at how that characteristic of the ocean changes as you go from the sea surface straight down to the seafloor. The spot we are going to explore is in the middle of the deep ocean.

Here are basic profiles for a site in the deep, open ocean roughly half-way between the equator and the North or South pole. In these profiles, temperature decreases as the water gets deeper while salinity and pressure increase with water depth. Here we are referring to the ocean pressure due to the weight of the overlying water ( equilibrium pressure), not to the pressure associated with a sound wave , which is much, much smaller. In general, temperature usually decreases with depth, salinity can either increase or decrease with depth, and pressure always increases with depth.

Depth profiles from the open ocean of temperature, salinity and density. Copyright University of Rhode Island.

From these profiles, it can be seen that temperature changes a large amount, decreasing from 20 degrees Celsius (°C) near the surface in mid-latitudes to 2 degrees Celsius (°C) near the bottom of the ocean. On the other hand, salinity changes by only a small amount, from 34 to 35 Practical Salinity Units (PSU), approximately 34 to 35 parts per thousand (ppt). Finally, pressure increases by a large amount, from 0 at the surface to 500 atmospheres (atm) at the bottom.

The speed of sound in water increases with increasing water temperature, increasing salinity and increasing pressure (depth). The approximate change in the speed of sound with a change in each property is:

Temperature 1°C = 4.0 m/s Salinity 1PSU = 1.4 m/s Depth (pressure) 1km = 17 m/s

Here is a typical sound speed profile for the deep, open ocean in mid-latitudes.

Profile of speed of sound in water. Note the sound speed minimum at 1000 meters. Copyright University of Rhode Island.

The decrease in sound speed near the surface is due to decreasing temperature. The sound speed at the surface is fast because the temperature is high from the sun warming the upper layers of the ocean. As the depth increases, the temperature gets colder and colder until it reaches a nearly constant value. Since the temperature is now constant, the pressure of the water has the largest effect on sound speed. Because pressure increases with depth, sound speed increases with depth. Salinity has a much smaller effect on sound speed than temperature or pressure at most locations in the ocean. This is because the effect of salinity on sound speed is small and salinity changes in the open ocean are small. Near shore and in estuaries , where the salinity varies greatly, salinity can have a more important effect on the speed of sound in water.

It is important to understand that the way sound travels is very much dependent on the conditions of the ocean. The sound speed minimum at roughly 1000 meter depth in mid-latitudes creates a sound channel that lets sound travel long distances in the ocean. The SOFAR Channel Section provides more information on how the sound speed minimum focuses sound waves into the channel.

Additional Links on DOSITS

• Science > How does sound travel long distances? The SOFAR Channel
• Science >  How does sound in air differ from sound in water?

Additional Resources

• BATS Lesson plans – The SOFAR Channel.
• NOAA Vents Program – The SOFAR or deep sound channel.
• NPL Technical Guides – Speed of Sound in Seawater.
• Physics Classroom – The Speed of Sound.
• PMEL Vents Acoustics Tutorial – Sound Speed.

NOTIFICATIONS

Sound in water.

• + Create new collection

Prof John Montgomery, the head of Auckland University Leigh Marine Laboratory, explains how sound travels in water and how this is different to how sound travels in air. He explains why sound can travel so much further in the ocean compared to on land.

Point of interest: In this clip. you’ll hear the ‘song’ of the humpback whale. The humpback whale song is known to travel large distances through the ocean.

PROF JOHN MONTGOMERY Sound in the marine environment hasn’t been that well studied, but we know, I guess, from our original work where the question was, we know that fish can detect reefs, but how do they detect it? And our hypothesis was that it was based on sound. So we went and tested that, and found that larval fish do orient towards reef sounds, so we could record reef sound on a reef, take it out into a place where there wasn’t a reef and it would show up thinking there was a reef there. So that gives a really good indication of the likely importance of the soundscape, that it may be an important cue for animals in terms of migrations to reefs.

One of the real advantages of sound from a biological point of view is that there is a lot of it there and that it travels really well. So it can give you information about things that are happening from long distances away, and clearly that’s important for all sorts of biological activity.

The main difference between sound in air and sound in water is that air is a far less dense medium, so it doesn’t take much to move air, but sound attenuates reasonably quickly with distance and air, whereas under water, you need a sound that’s intense enough to move the water, which is quite dense and heavy, but it’s not very compressible so the sound then will propagate long distances.

In water, marine creatures can hear sound from vast distances and the extreme is probably the song of the humpback whale. and that sound can travel across whole oceans. so you could get, potentially, humpbacks at one end of the Pacific listening to humpbacks at the other.

Acknowledgement: Canadian Broadcasting Corporation Andrew Stevenson http://www.youtube.com/watch?v=eOS20plm7UM

Sound on the move

Sound is a pressure wave, but this wave behaves slightly differently through air as compared to water. Water is denser than air, so it takes more energy to generate a wave, but once a wave has ...

Hearing sound

Three components are needed for sound to be heard: A source – where the sound is made. A medium – something for the sound to travel through. A receiver – something to detect the sound. Source ...

See our newsletters here .

Would you like to take a short survey?

This survey will open in a new tab and you can fill it out after your visit to the site.

• Random article
• Teaching guide
• Privacy & cookies

by Chris Woodford . Last updated: July 23, 2023.

Photo: Sound is energy we hear made by things that vibrate. Photo by William R. Goodwin courtesy of US Navy and Wikimedia Commons .

What is sound?

Photo: Sensing with sound: Light doesn't travel well through ocean water: over half the light falling on the sea surface is absorbed within the first meter of water; 100m down and only 1 percent of the surface light remains. That's largely why mighty creatures of the deep rely on sound for communication and navigation. Whales, famously, "talk" to one another across entire ocean basins, while dolphins use sound, like bats, for echolocation. Photo by Bill Thompson courtesy of US Fish and Wildlife Service .

Robert Boyle's classic experiment

Artwork: Robert Boyle's famous experiment with an alarm clock.

How sound travels

Artwork: Sound waves and ocean waves compared. Top: Sound waves are longitudinal waves: the air moves back and forth along the same line as the wave travels, making alternate patterns of compressions and rarefactions. Bottom: Ocean waves are transverse waves: the water moves back and forth at right angles to the line in which the wave travels.

The science of sound waves

Picture: Reflected sound is extremely useful for "seeing" underwater where light doesn't really travel—that's the basic idea behind sonar. Here's a side-scan sonar (reflected sound) image of a World War II boat wrecked on the seabed. Photo courtesy of U.S. National Oceanographic and Atmospheric Administration, US Navy, and Wikimedia Commons .

Whispering galleries and amphitheaters

Photos by Carol M. Highsmith: 1) The Capitol in Washington, DC has a whispering gallery inside its dome. Photo credit: The George F. Landegger Collection of District of Columbia Photographs in Carol M. Highsmith's America, Library of Congress , Prints and Photographs Division. 2) It's easy to hear people talking in the curved memorial amphitheater building at Arlington National Cemetery, Arlington, Virginia. Photo credit: Photographs in the Carol M. Highsmith Archive, Library of Congress , Prints and Photographs Division.

Measuring waves

Understanding amplitude and frequency, why instruments sound different, the speed of sound.

Photo: Breaking through the sound barrier creates a sonic boom. The mist you can see, which is called a condensation cloud, isn't necessarily caused by an aircraft flying supersonic: it can occur at lower speeds too. It happens because moist air condenses due to the shock waves created by the plane. You might expect the plane to compress the air as it slices through. But the shock waves it generates alternately expand and contract the air, producing both compressions and rarefactions. The rarefactions cause very low pressure and it's these that make moisture in the air condense, producing the cloud you see here. Photo by John Gay courtesy of US Navy and Wikimedia Commons .

Why does sound go faster in some things than in others?

Chart: Generally, sound travels faster in solids (right) than in liquids (middle) or gases (left)... but there are exceptions!

How to measure the speed of sound

Sound in practice, if you liked this article..., don't want to read our articles try listening instead, find out more, on this website.

• Electric guitars
• Speech synthesis
• Synthesizers

On other sites

• Explore Sound : A comprehensive educational site from the Acoustical Society of America, with activities for students of all ages.
• Sound Waves : A great collection of interactive science lessons from the University of Salford, which explains what sound waves are and the different ways in which they behave.

Educational books for younger readers

• Sound (Science in a Flash) by Georgia Amson-Bradshaw. Franklin Watts/Hachette, 2020. Simple facts, experiments, and quizzes fill this book; the visually exciting design will appeal to reluctant readers. Also for ages 7–9.
• Sound by Angela Royston. Raintree, 2017. A basic introduction to sound and musical sounds, including simple activities. Ages 7–9.
• Experimenting with Sound Science Projects by Robert Gardner. Enslow Publishers, 2013. A comprehensive 120-page introduction, running through the science of sound in some detail, with plenty of hands-on projects and activities (including welcome coverage of how to run controlled experiments using the scientific method). Ages 9–12.
• Cool Science: Experiments with Sound and Hearing by Chris Woodford. Gareth Stevens Inc, 2010. One of my own books, this is a short introduction to sound through practical activities, for ages 9–12.
• Adventures in Sound with Max Axiom, Super Scientist by Emily Sohn. Capstone, 2007. The original, graphic novel (comic book) format should appeal to reluctant readers. Ages 8–10.

Popular science

• The Sound Book: The Science of the Sonic Wonders of the World by Trevor Cox. W. W. Norton, 2014. An entertaining tour through everyday sound science.

Academic books

• Master Handbook of Acoustics by F. Alton Everest and Ken Pohlmann. McGraw-Hill Education, 2015. A comprehensive reference for undergraduates and sound-design professionals.
• The Science of Sound by Thomas D. Rossing, Paul A. Wheeler, and F. Richard Moore. Pearson, 2013. One of the most popular general undergraduate texts.

Text copyright © Chris Woodford 2009, 2021. All rights reserved. Full copyright notice and terms of use .

Rate this page

Tell your friends, cite this page, more to explore on our website....

• Get the book
• Send feedback

How Far Does Sound Travel: The Science of Acoustics

Do you ever stop to think about how sound travels? It’s an interesting phenomenon that occurs everyday and yet we often take it for granted. In this blog post, we will explore the science of acoustics and how sound travels. We will answer the question of how far sound can travel and how it is affected by different factors. Stay tuned for an in-depth look at this fascinating topic!

Nature Of Sound

Sound is a mechanical wave that is an oscillation of pressure transmitted through some medium, such as air or water. Sound can propagate through solids and liquids better than gases because the density and stiffness are greater. So how far does sound travel? In this article we will answer how sound travels and how to calculate how far it travels in different scenarios.

Sound Transmits Conception

A common misconception with regard to how sound transmits itself between two points (for example from speaker to ear) is that the source creates waves of compression in the surrounding gas which then proceed on their way at a constant speed until they strike something else; either another solid object or our ears . This analogy might be okay for describing what goes on at low frequencies but once we go beyond around 1000 Hz, the propagation of sound becomes far more complex.

At low frequencies (below around 1000 Hz), sound waves tend to travel in all directions more or less equally and bounce off objects like a rubber ball would. As frequency increases however, the directivity of sound increases as well. So high-frequency sounds are more likely to travel in a straight line between two points than low frequencies. This is why we can often hear someone calling from some distance away when there is loud music playing – because the higher frequencies carry further than the lower ones.

How Far Can Sound Travel

There are three ways that sound can be transmitted: through air, through water, or through solids. The speed of sound through each medium is different and depends on the density and stiffness of the material.

The speed of sound through air is about 343 m/s (or 760 mph), and it travels faster in warmer air than colder air. The speed of sound through water is about 1500 m/s, and it travels faster in salt water than fresh water. The speed of sound through solids is much faster than through either gases or liquids – about 5000-15000 m/s. This is why we can often hear someone coming before we see them – the sound waves are travelling through the solid ground to our ears!

Now that we know how sound propagates and how its speed depends on the medium, let’s take a look at how to calculate how far it will travel between two points. We can use the equation

distance = speed x time

For example, if we want to know how far a sound will travel in one second, we have:

distance = 343 m/s x 0.001 s = 343 m

So sound travels 1 kilometer in roughly 3 seconds and 1 mile in roughly 5 seconds.

Does Вecibel Level affect the Sound Distance?

The surface area around a sound source’s location grows with the square of the distance from the source. This implies that the same amount of sound energy is dispersed over a larger surface, and that the energy intensity decreases as the square of the distance from the source (Inverse Square Law).

Experts of Acoustical control says, that

For every doubling of distance, the sound level reduces by 6  decibels  (dB), (e.g. moving from 10 to 20 metres away from a sound source). But the next 6dB reduction means moving from 20 to 40 metres, then from 40 to 80 metres for a further 6dB reduction.

How Far Can Sound Travel In Real World

In real world, there are many factors that can affect how far a sound travels. Factors such as air density, temperature and humidity have an impact on its propagation; obstacles like buildings or mountains could also block some frequencies from going through while letting others pass (this happens because at high frequencies they behave more like waves).

Sounds can propagate through solids better than they can propagate through air because their density/stiffness are greater (this means that sound travels faster). In addition to this, we also know that it takes less time for a high frequency wave to reach us from its source compared with low frequencies. For example if there’s some kind of obstacle blocking our path then it might take longer for waves at higher frequencies than those below 1000 Hz to past them.

Can Sound Waves Travel Infinitely?

No. The higher the frequency of a sound wave, the shorter its wavelength becomes. As wavelength decreases, the amount of energy in a sound wave also decreases and eventually it dissipates completely. This is why we often can’t hear someone calling from very far away when there’s loud music playing – because the high frequencies are being blocked out by all the noise!

Can Sound Travel 20 Miles?

The air may be permeable to these lower-frequency, sub-audible sound waves generated by elephants. Some whale species’ frequencies might travel through seawater for 1500 kilometers or 900 miles.

How Far Can a Human Scream Travel?

The normal intelligible outdoor range of the male human voice in still air is 180 m (590 ft 6.6 in).

The Guiness World Record of the Farthest distance travelled by a human voice belongs the Spanish-speaking inhabitants of the Canary Island of La Gomera, is intelligible under ideal conditions at 8 km (5 miles).

In Conclusion

At the end of this blog post, you should have a better understanding of how sound travel and what factors affect it. If you want to learn more about acoustics and sounds, you can check out our resources here.

• Why PS4 Is So Loud and How to Fix It
• Best Quiet Electric Toothbrush – Buyer’s Guide

Which Strategy is Best for Reducing Noise Pollution in Our Community?

Ocean Noise Pollution: What Is It?

Does Sound Travel Faster in Water or Air?

Most people, whether they are students or workers, have a pretty clear idea of how sound works. After all, who hasn’t heard about sound waves, vibrations, and other similar concepts? Yet, there are a few notions that still baffle people to this day, particularly regarding the way sound propagates in water and air. And, with so much contradictory information online, it’s easy to see why.

So, if you’re one of the many who want to know if sound travels faster in water or air, this article has got you covered. But first, let’s start with the basics!

Temperature and Pressure

What is sound.

Generally speaking, sound is a type of longitudinal mechanical wave that travels through a medium. However, there are two definitions regarding how sound is produced.

For starters, in physiology, sound is created when an object’s vibrations travel through a medium until they reach the human eardrum . In physics, sound is produced in the form of a pressure wave . More specifically, when objects vibrate, they cause the nearby molecules to also vibrate, triggering a chain reaction of sound wave vibrations in the specific medium.

But no matter which definition you prefer, you’ll notice a similarity — sound needs a medium to propagate and will not travel through a vacuum. As a matter of fact, sound travels at different speeds depending on the medium. In other words, the medium’s density and compressibility directly affect the speed of sound. For instance, sound waves will travel slower in a less dense and more compressible medium .

How Fast Does Sound Travel in Water?

When it comes to water, sound can travel as fast as 1,498 meters per second, or approximately 3,350 miles per hour . However, as mentioned earlier, the physical characteristics of the medium highly affect the speed.

As a result of its high salinity, seawater, such as oceans, allows sound to travel up to 33 meters per second faster than the freshwater found in lakes . That’s because salt molecules respond quickly to the disturbances of neighboring molecules, propagating sound waves faster and at longer distances.

The speed of sound is also dependent on density. As you might already know, water has an impressive density due to its unique molecular arrangement. Thus, sound waves can travel much faster underwater as the wave bumps and vibrates with more molecules.

You need to understand that, as the ocean gets deeper, its temperature decreases and its pressure increases. These affect the particle arrangement and, by extension, the speed of sound. To put it simply, sound travels slower at the surface level than at lower depths.

How Fast Does Sound Travel in Air?

Sound is able to travel through the air at an average of 332 meters per second, or 742 miles per hour. Although that might seem fast, it is not nearly as fast as light , which travels at 186,411.358 miles per hour. But as with water, there are also many factors that affect how sound propagates in the air:

Temperature

Air molecules tend to have more energy at higher temperatures, meaning that they will vibrate faster. That allows sound waves to also travel faster and farther , as they are propelled by molecule collisions. Yet, as the sound moves through the atmosphere, some parts of its wave will travel faster than others due to temperature differences.

What’s interesting about sound is that, at a constant temperature, its speed is not dependent on the pressure of the medium. That’s because these two properties are tied to one another. So, increasing temperature will also increase pressure and, consequently, the speed of sound.

Air Direction

The wind direction can impact the speed of sound and the distance it can travel . In fact, you might notice that sound levels are higher when the wind is blowing down, such as from a highway towards the ground level.

Water vapors are less dense than dry air at a constant temperature. Naturally, the presence of moisture will decrease the air’s density and increase the speed of sound. Therefore, humid environments experience much faster sound propagation than dry and cold areas.

Why Does Sound Travel Faster in Water Than Air?

By now, you might have noticed that sound travels about four times faster in water than in air. The main reason behind this is that water is denser than air. Sure, not all water has identical properties , as salinity and temperature vary and affect its density. But even so, molecules in the water are closer together, causing more vibrations to be transmitted at a faster speed of sound.

Furthermore, water is an incompressible environment . Actually, it’s better to imagine water as being similar to a solid object, as they tend to behave similarly when it comes to compression. More specifically, when water encounters a force, it will immediately transfer its energy to nearby molecules, just like solids. This characteristic is partially offset by the water’s high density, creating the perfect environment for sound to travel through.

And lastly, it’s important to mention that sound travels faster in harder materials . It’s true that water as a unit is not necessarily hard; however, it has a strong bond between its molecules. Hence, the propagation of sound is faster as it passes more quickly from one particle to the next.

But Why Is It Harder to Talk to Someone Underwater?

Naturally, you might assume that, since sound travels faster in water, it would be incredibly easy to chat with someone while swimming or diving . But that couldn’t be further from the truth.

When someone talks, they do so by emitting air and sending compression waves through it. That’s thanks to your lungs, vocal cords, and mouth, which work together to imprint a sound waveform on the burst of air that comes from your body. So, in order for someone that’s in the water to hear you, the sound will need to travel from your mouth into the surrounding water.

However, sound couples very poorly from air to water. As a matter of fact, water tends to reflect external sound waves instead of allowing them to penetrate its surface. That’s also the reason why phenomenons like echos occur when you scream or talk near a well, as the water at its bottom reflects the sound waves back to you.

What About Sound Travel Distance?

When it comes to sound travel, water is again the clear winner, as it allows sound to propagate to distances of almost 15,500 miles. To understand why that’s the case, imagine a whale that is swimming through the ocean and calls out to its peers. The sound waves it produces move similarly to ripples in the water.

As the sound travels and reaches increasing depths , it begins to slow down and eventually refracts downward. Once the sound reaches a region called the thermocline layer, its speed further decreases to a minimum. That’s because the thermocline layer features rapid changes in pressure and temperature.

After breaking through the layer, sound waves encounter another area where the temperature remains constant. However, the pressure continues to rise, which causes a boost in the sound speed, making it refract upward. This channeling of waves allows the sound to travel thousands of miles with little to no energy loss. It’s thanks to this process that scientists can pick up whale songs from many miles away.

Key Takeaways

Understanding how sound works and travels is extremely important. Sure, you might not deal with mediums like water every day. However, air is all around you, and learning the way it affects sound speed can help you figure out the perfect way to soundproof your environment and enjoy a noise-free life!

RELATED POSTS:

• Does Sound Travel Faster Than Light?
• Does Sound Travel Up Or Down?
• How To Keep Sound In A Room
• Best Sound Absorbing Materials

Leave a Comment Cancel Reply

Your email address will not be published. Required fields are marked *

Sound Science Experiment: Can sound travel through water? Build a hydrophone

Make your own hydrophone to listen for sounds underwater.

 Monster Sciences Sound Experiment:  Can you hear underwater?

What you will need:.

• A large bowl half full of water
• An empty plastic soft drink bottle with no lid
• 2 hard things, e.g. pebbles, marbles, metal spoons

What you will do:

• Gently click the hard things (pebbles, spoons etc) together.  How do they sound?
• Place your bowl of water on a table or the ground so it is no higher off the ground than your waist.
• VERY CAREFULLY cut the bottom off your plastic container, about level with the bottom of the label.
• Put the bottle, cut side down, into the bowl of water and put your ear up against the hole at the other end.
• Ask your partner to gently tap the spoons or other hard things together under the water.  What can you hear?
• Swap and let your partner listen.

  What is going on?

You are listening to the sound waves from the clicking traveling through the water.  Sound travels in waves caused by vibrations, bumping the molecules around them together.  Does the sound travel through the air better than the water, or the water better than the air?  Compare it to a solid by tapping the hard object gently on the table while you put your ear against it.  What did you discover?

  Monster Challenges: 

• The bottle you have cut off catches sound waves – how else could you use it for this?  Could you make a phone?  How?
• The bottle can also be used to magnify sound waves.  Can you figure out how?
• Try this next time you’re swimming!

Teaching Notes:

Key concepts:.

Sound travels in waves.

• Investigation Record IR01– one copy per student
• Experiment Description Sound S04– one copy per student
• Large bowl with water, empty soft drink bottle, scissors, hard objects

Lesson Notes:

When doing this experiment with younger students I usually cut down the bottles myself prior to the lesson.

The hard objects can be anything water proof.  Remind students not to tap them too hard – it can be too loud!

As a class discuss the experiment prior to undertaking it, and students should complete the sections of their Investigation Report IR01 from ”Title to “Hypothesis”.

What should happen in this experiment, and why?

The students should be able to clearly hear the clicking underwater, in fact is should be easier to hear and clearer than in the air.  This is because the molecules in a liquid like water are closer together so bounce off each other more effectively than the molecules of air.  The solid table should transfer the sound even better than the water because its molecules are closer together again.

The children should note that the clicking rocks vibrate the water, the vibration creates sound waves which vibrate the bottle and then the air inside it to carry the sound to their ear.  If their ear was in the water the sound is even better.

Follow up discussion questions:

• How do whales and dolphins use sound in the water?
• What about submarines?
• Can you think of a way to use water to improve a string phone?  (If you wet the string between the cups closely packed water molecules replace the loosely packed air molecules within the fibers of the string).

Get this experiment here or as part of a bundle of Sound Experiments here .

Written by admin

View all posts by: admin

Welcome to the Official Website of Moscow WSC

Our mission.

At Moscow WSC, we are committed to providing safe, high quality water services to our community, while maintaining a standard of excellence in customer service and environmental conservation.

Bill Payment Options

Looking for the most convenient way to pay your bill? We offer a wide variety of payment options to our customers. Simply choose the option that best suits your needs... Payment Options...

Conservation Tips

There are a number of easy ways to save water, and they all start with you. When you save water, you save money on your utility bills. Here are just a few ways... Conservation Tips

Recent News View All »

• Subscribe Today! Moscow WSC Website!

July 03, 2024

We are excited to announce that our new website has launched and includes all the information our community needs related to their water service. Check back often, as we will be adding information every day. Subscribe and receive news and alerts via email and text. Let us know what you think!

Read More »

It’s Water Quality Awareness Month

August 01, 2024

As August dawns upon us, it's time to shine a spotlight on one of the most essential resources we often take for granted: clean, safe drinking water. August is Water Quality Awareness Month, a time to recognize the vital role that water operators play in ensuring that our taps flow with clean, safe water every day.

Read the full article »

Receive news and alerts via email or text.

Sign Up for Alerts

Unsubscribe --> Unsubscribe

Recent News

Related links.

• Texas Rural Water Association
• National Rural Water Association
• Water Conservation Tips
• Environmental Protection Agency
• Affordable Water Utility Websites

No Alerts at this time.

Subscribe to the Website

1. Receive our News , Projects and ALERTS via Email:

2. Receive ALERTS via Text Message:

(Enter 10 Digit Cell Number xxx-xxx-xxxx)

By providing an email and/or cell number and clicking the “Subscribe” button, you are (1) consenting to receive email & text notifications and (2) acknowledging that you have read, understand, and agree to our Terms of Use and Privacy Policy .

Ukraine war latest: Russia and Ukraine swap 115 prisoners as Zelenskyy celebrates independence day

Russia and Ukraine have swapped 115 prisoners of war, including some who were captured during Ukraine's incursion in Kursk in recent weeks. Meanwhile, Ukraine is celebrating independence day, with Sir Keir Starmer sending his "warmest wishes".

Saturday 24 August 2024 18:59, UK

• Ukraine and Russia exchange 115 prisoners of war 
• Muted celebrations for Ukraine's independence day | Sir Keir Starmer sends "warmest wishes"
• Residents evacuate key eastern town as Russian troops advance
• Putin has 'made decision' on responding to Kursk invasion
• Your questions answered : Is there a larger response to come from Russia over the Kursk invasion?
• Live reporting by Katie Williams

Volodymyr Zelenskyy has used an independence day address to brand Vladimir Putin a "sick old man from Red Square".

In a video address to the Ukrainian people, Mr Zelenskyy used derisive language to describe Russia's 71-year-old president and his nuclear rhetoric.

"A sick old man from Red Square who constantly threatens everyone with the red button will not dictate any of his red lines to us," the Ukrainian leader said in the video posted to Telegram.

In his speech, Mr Zelenskyy noted that the war started by Russia had spread to its own territory.

"Those who seek to sow evil on our land will reap its fruits on their own soil," he said.

He also said "those who sought to turn our lands into a buffer zone should now worry that their own country doesn't become a buffer federation".

Five people have been injured after a Russian shelling in Ukraine's northeastern Kharkiv region, authorities have said.

The country's state emergency service said Russian forces targeted the village of Novoosynove in the Kupyan district with rockets today.

Four women and a man were injured, it said, while two residential buildings and an area of dry grass caught fire.

"Rescuers extinguished the fire and prevented the flames from spreading to other homes," the emergency service said on Telegram, adding that medics were at the site of the attack.

Ukraine has targeted Russian forces with a new domestically-produced missile drone for the first time, Volodymyr Zelenskyy has said.

Speaking during independence day celebrations, the Ukrainian president said the faster and more powerful Palianytsia represents a "completely new class" of weapon.

He did not give details about where the weapon was used against Russian troops -  but said the "enemy was struck".

"We know that in Russia, it will be very difficult. Difficult even to understand what exactly hit them. Difficult to counteract, but very easy to understand why," he said.

Russian forces are now just several miles from the strategic city of Pokrovsk in Ukraine's eastern Donetsk region.

The city - which lies at an intersection of roads and a railway that makes it an important logistics point - has been in Moscow's sights for months, with fighting raging in nearby areas.

Authorities ordered families with children to leave Pokrovsk earlier this week and have stepped up appeals for all other civilians to flee.

One supermarket is being stripped of its shelves before it is closed due to the Russian advance, while residents elsewhere are hauling belongings out of their homes as they prepare to evacuate. 

There is a "solemn" atmosphere at an event to mark the 33rd anniversary of Ukraine's independence in west London, says our news correspondent Shamaan Freeman-Powell .

Around 100 people have gathered in Holland Park for the event which is being held at the statue of Saint Volodymyr.

"I have been told that usually there are parades, concerts, fireworks even to mark Ukraine's independence from the old Soviet Union," Powell says.

"This year, though, the event is more of a solemn one."

Some at the London gathering have said they wouldn't want to celebrate Ukraine's independence, but are marking the occasion against the backdrop of the war which has seen many Ukrainians forced to flee to Britain.

"In fact, some of them are a part of this celebration today," Powell says.

She spoke to one woman who broke down in tears when asked why the event was important to her.

Powell adds: "She says that she wants to remind the world about the war that's currently taking place. She says [to] remember that the greatest people of Ukraine fought for that independence."

Some MPs are expected to give speeches later, while a moment of silence will also be held, she says.

The US is still reluctant to let Ukrainian forces use Western-supplied long-range weapons inside Russia despite pressure from Kyiv, according to a report.

Volodymyr Zelenskyy has long urged Ukraine's allies to permit long-range missile strikes across Russian borders.

Politico reports that the Ukrainian invasion of Kursk has prompted fresh pressure from Kyiv on Washington to lift its restrictions - but the White House is still not ready to allow it.

Ukrainian officials have reportedly been pressing Joe Biden and his top advisers to put aside the fear of a Russian escalation and allow Ukraine to fight on its own terms.

But some top US national security officials believe the public campaign on long-range weapons by Ukraine may be a move to hedge against any significant loss of ground in the months ahead, one source close to the discussions told Politico.

Some officials have also told Kyiv that lifting its restrictions could hamper future efforts by the US to reset its relations with Russia, it said.

Washington has announced a fresh $125m (£94.6m) package of military aid for Ukraine.

The US defence department said the additional aid was aimed at meeting Kyiv's "most urgent needs", including air defence capabilities, munitions for rocket systems and artillery and anti-tank weapons.

The US president spoke to Volodymyr Zelenskyy as the aid was announced and reaffirmed America's "unwavering" support for Kyiv, the White House said.

"Ukraine critically needs the supply of weapons from the announced packages, particularly additional air defence systems for the reliable protection of cities, communities, and critical infrastructure," Mr Zelenskyy said in a statement after the call released by his office. 

Volodmyr Zelenskyy says Ukraine's invasion of Russia's Kursk region was a preventative move to halt Russian attacks in northern Ukraine and on the city of Sumy.

He told a news conference that the invasion was difficult but had made positive progress.

Mr Zelenskyy added that as well as capturing Russian soldiers, the cross-border invasion had other goals he could not disclose.

Russia's defence ministry said earlier that 115 Russian soldiers involved in a prisoner swap with Ukraine today had been captured in Kursk (see 13.18 post).

Ukrainian forces have gained fresh momentum from the invasion of Kursk invasion three weeks ago - and the delayed arrival of US weaponry this month.

Officials say they have taken about 100 square kilometres (62 square miles) of territory around Kursk.

A Russian-installed official in occupied Ukraine has boasted about burning Ukrainian books and called for "Ukrainianness" to be "burnt out at the root".

In its latest intelligence update, the UK Ministry of Defence reported the comments made by Dmitry Rogozin, senator for the Russian-controlled parts of Zaporizhzhia, which he posted on Telegram.

Mr Rogozin also said any truce in the war would amount to "certain death" for Russian children.

The MoD said the remarks were "the latest in a long line of Ukrainophobic comments" by senior Russian officials.

It said there were "likely many individuals" within Russia who still have "maximalist objectives" for the conflict - "including the destruction of Ukrainian culture, identity and statehood".

"This is despite the alleged Russian willingness to negotiate," the MoD commented.

At least five people have been killed at five others injured in a Russian attack in eastern Ukraine, a local official has said.

Vadym Filashkin, governor of the Donetsk region, said the emergency workers were at the scene of the attack in the town of Kostiantynivka.

"I urge you all again: take care of yourselves, evacuate," he wrote on Telegram, without providing more details. 

Kostiantynivka is near the location of heavy fighting in Donetsk, where Russian forces have been making advances for months.

The advance has quickened in recent weeks as Moscow's troops push towards the key town of Pokrovsk.

This is the latest situation on the ground in eastern Ukraine:

Be the first to get Breaking News

Install the Sky News app for free

• ₹ 10 Lakh,1" data-value="Loan ₹ 10 Lakh">Loan ₹ 10 Lakh
• Games & Puzzles

• Entertainment
• Latest News
• Kolkata doctor rape case LIVE
• Shikhar Dhawan Retirement
• NEET PG 2024 Result Live
• Web Stories
• Mumbai News
• Bengaluru News
• Daily Digest

Russia says repels drone attack on Moscow

Ukraine fired 11 drones Wednesday at Moscow that Russia said were shot down during one of the largest strikes against the capital, while Ukrainian defences reported stopping 50 Russian drones and missiles.

The strikes on Moscow come amid a Ukrainian offensive in Russia's Kursk region which Kyiv has said is aimed at bringing the campaign launched by Russia in February 2022 closer to an end on "fair" terms.

"Eleven drones were destroyed" over Moscow and its surrounding region, the defence ministry said.

"This is one of the largest ever attempts to attack Moscow with drones," Moscow Mayor Sergei Sobyanin said.

In total, 45 drones from Ukraine were destroyed by the Russian air defense systems, according to the Russian defense ministry.

Sobyanin said in an earlier post that no damage or casualties had been reported.

Drone attacks on Moscow are rare, with Russia saying in May it had downed a drone outside the capital, forcing restrictions to be imposed at two major airports in the city for under an hour.

In the night from Tuesday to Wednesday, a total of 72 air targets were detected over Ukraine, according to Ukrainian Air Force Commander Mykola Oleshchuk.

Fifty drones and a guided missile were shot down, he said in a post on Telegram.

Kyiv was one of the locations targeted.

"The enemy continues to attack our region with strike drones. The air raid lasted all night and into the morning for more than nine hours," Kyiv's military administration said on Telegram.

A private house was damaged as a result of falling debris from the downed targets, and power lines were cut, it added.

Since August 6, Ukraine has mounted an unprecedented cross-border assault into Russia's Kursk region, where it claims to control more than 80 settlements.

Kyiv has also repeatedly targeted oil and gas facilities in Russia since the conflict began in 2022, some hundreds of kilometres from its borders, in what it has called "fair" retaliation for massive attacks on its energy infrastructure.

Ukrainian drones attacked an oil storage facility in Russia's southern Rostov region on Sunday, sparking a large fire, the local governor said.

The blaze in the city of Proletarsk was still raging on Wednesday, Russian media reported.

Earlier this month, Ukrainian President Volodymyr Zelensky praised his forces for hitting oil facilities in Russia, saying the attacks would help bring a "just end" to the conflict.

This article was generated from an automated news agency feed without modifications to text.

• Terms of use
• Privacy policy
• Weather Today
• HT Newsletters
• Subscription
• Print Ad Rates
• Code of Ethics

• India vs Sri Lanka
• Live Cricket Score
• Cricket Teams
• Cricket Players
• ICC Rankings
• Cricket Schedule
• Shreyas Iyer
• Harshit Rana
• Kusal Mendis
• Ravi Bishnoi
• Rinku Singh
• Riyan Parag
• Washington Sundar
• Avishka Fernando
• Charith Asalanka
• Dasun Shanaka
• Khaleel Ahmed
• Pathum Nissanka
• Other Cities
• Income Tax Calculator
• Petrol Prices
• Diesel Prices
• Silver Rate
• Relationships
• Art and Culture
• Taylor Swift: A Primer
• Telugu Cinema
• Tamil Cinema
• Board Exams
• Exam Results
• Admission News
• Employment News
• Competitive Exams
• BBA Colleges
• Engineering Colleges
• Medical Colleges
• BCA Colleges
• Medical Exams
• Engineering Exams
• Love Horoscope
• Annual Horoscope
• Festival Calendar
• Compatibility Calculator
• Career Horoscope
• Manifestation
• The Economist Articles
• Lok Sabha States
• Lok Sabha Parties
• Lok Sabha Candidates
• Explainer Video
• On The Record
• Vikram Chandra Daily Wrap
• Entertainment Photos
• Lifestyle Photos
• News Photos
• Olympics 2024
• Olympics Medal Tally
• Other Sports
• EPL 2023-24
• ISL 2023-24
• Asian Games 2023
• Public Health
• Economic Policy
• International Affairs
• Climate Change
• Gender Equality
• future tech
• HT Friday Finance
• Explore Hindustan Times
• Privacy Policy
• Terms of Use
• Subscription - Terms of Use