“This image makes the invisible visible,” said ... Turns out, under certain conditions, the sound waves refract in the ...

"This image makes the invisible visible — the first American made civil supersonic jet breaking the sound barrier." ...

We can't hear these sound waves, but when they reflect off different parts of the body, they create echoes that are picked up by the probe and turned into an image called an ultrasound scan.

Sound is a vibration that travels through air as a wave. These waves are created when an object moves back and forth, compressing and decompressing air molecules. The frequency of these vibrations ...