As a field expert in acoustics and physics, I can explain the phenomenon of sound transmission and its limitations in different environments. Sound is a mechanical wave that requires a medium, such as air, water, or solids, to travel. This is because sound is produced by the vibration of particles in a medium, and these vibrations are what we perceive as sound. On Earth, sound travels to our ears by causing the air molecules around us to vibrate. These vibrations then propagate through the air in the form of pressure waves, which our ears detect and our brain interprets as sound. In deep space, the situation is quite different. Space is often referred to as a vacuum, which means it is largely devoid of matter, including the molecules necessary for sound to propagate. Without these molecules to vibrate and transfer the energy of the sound wave, sound cannot travel through space. Even in regions of space where there are very few molecules, the density is so low that the ability for sound to travel is effectively nonexistent. To summarize, sound cannot travel through an empty space because there are no particles to vibrate and carry the sound wave. The propagation of sound requires a medium with molecules that can interact with each other, and in the vacuum of space, such a medium is absent. read more >>

So, in order for sound to travel, there has to be something with molecules for it to travel through. On Earth, sound travels to your ears by vibrating air molecules. In deep space, the large empty areas between stars and planets, there are no molecules to vibrate.read more >>