Is there a sound barrier in space

Sound barrier

Sound barrier, Term for the pressure wave that occurs when the speed of a moving sound source exceeds the speed of sound (see Fig. 1). Breaking this ›sound barrier‹ turns into a loud bang, the Sonic boom (Bullet crack) audible. The at Supersonic speed strongly compressed air expands behind the sound source like an explosion. This phenomenon is particularly well known in missiles. In moist, water vapor-saturated air, water can even condense out there due to the shock wave - a cloud is formed (see Fig. 2).

Sound barrier 1: Creation of a sound barrier. a) A stationary sound source (e.g. missile) emits spherical waves, the maxima of which are everywhere the same distance from the next maximum. b) If the sound source moves, the maxima in front of the source crowd together in the direction of movement and move away from each other behind it. c) This process intensifies with increasing speed, the sound source approaches the compressed maxima. When the speed of sound is reached, a single pressure wave is created, the sound barrier. d) If the speed is increased further, the sound source breaks the sound barrier with a bang. The individual spherical pressure waves are generated by the so-called. Mach cone enveloped. the sound source is at the top.

Sound barrier 2: Visible breach of the sound barrier. (Photo: AP)