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Sonar

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Sonar is a clever way to find things using sound. The name stands for sound navigation and ranging. It helps people navigate through the water or find objects on the sea floor.

Sonar Principle EN
Sonar Principle EN

Scientists use it to measure distances or to communicate. There are two main ways that sonar works. Passive sonar means just listening for sounds made by other vessels. Active sonar means sending out a pulse of sound and listening for the echo that bounces back.

Fishfinder
Fishfinder

Active sonar works in a specific way to find targets. First, an acoustic transducer creates a sound wave. This wave travels through the water until it hits an object. Then, the sound reflects off that object and travels back to the ship. This reflection is called an echo. By measuring the echo, people can find the location of a target.

Sonar Principle EN
Sonar Principle EN

Some systems even use special crystals to turn electricity into these sound waves. These crystals can be made of materials like quartz or ADP.

Humans have used sound to find things for a very long time. In 1490, Leonardo da Vinci used a simple tube in the water. He would put his ear to the tube to hear boats.

Humpback Whale underwater shot
Humpback Whale underwater shot

Later, in 1912, the sinking of the Titanic prompted more research. An English meteorologist named Lewis Fry Richardson filed a patent for an echo-ranging device. In 1914, a Canadian engineer named Reginald Fessenden tested a system in the Grand Banks off Newfoundland. He successfully used it to find an iceberg and send Morse code.

Miinitraaleri "Virsaitis" vrakk
Miinitraaleri "Virsaitis" vrakk

During World War I, sonar became very important for finding submarines. The British developed a secret system called ASDIC. This name was used to keep the work a secret from others.

ASDIC
ASDIC

By 1923, some British ships were already using ASDIC. In the United States, engineers like J. Warren Horton helped improve these tools. He used vacuum tubes to detect underwater signals. This work helped replace old carbon button microphones with better tools.

Watch floor
Watch floor

These improvements made it much easier to find mines and torpedoes.

Today, we use sonar for many different jobs. It helps robots move safely through the ocean.

Sonar operations by survey ship
Sonar operations by survey ship

It is also used to find things like debris from the Space Shuttle Columbia.

Some ships even use variable depth sonar to look deeper.

Variabel dybde sonar (VDS) på et af søværnets skibe af Thetis-klassen
Variabel dybde sonar (VDS) på et af søværnets skibe af Thetis-klassen

Just like dolphins use sound to navigate, humans use sonar to understand the underwater world.

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🖼️ Images & Media (14)
File:Motte-Picquet-tugged-sonar.jpg
Motte-Picquet-tugged-sonar.jpg
File:Miinitraaleri "Virsaitis" vrakk.jpg
Miinitraaleri "Virsaitis" vrakk.jpg
File:ASDIC.png
ASDIC.png
File:Sonar Principle EN.svg
Sonar Principle EN.svg
File:Undersea bubble clouds.jpg
Undersea bubble clouds.jpg
File:TWIPS picture 2.png
TWIPS picture 2.png
File:Variabel dybde sonar (VDS) på et af søværnets skibe af Thetis-klassen.jpg
Variabel dybde sonar (VDS) på et af...
File:SH-3H HS-15 lowers AQS-13 sonar 1979.JPEG
SH-3H HS-15 lowers AQS-13 sonar 1979.JPEG
File:Watch floor.gif
Watch floor.gif
File:US Navy 030223-N-7479T-011 An AN-PQS-2A, a handheld sonar device used to aid in the search of the Toledo Bend Reservoir for debris from the Space Shuttle Columbia.jpg
US Navy 030223-N-7479T-011 An AN-PQS-2A,...
File:Fishfinder.jpg
Fishfinder.jpg
File:Sonar operations by survey ship.jpg
Sonar operations by survey ship.jpg

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