Does Sound really travel in space?
Most of us have watched at least a few
science fiction films or shows and have grown accustomed to the fact that
people in outer space would still be able to hear one another speak and other
such sounds while they were exploring or travelling in outer space.
Hollywood directors love using sound effects in outer space to add drama. But are these sounds really possible? Many of the sounds that occur during times of space travel have never been heard before by human ears. Therefore by re-creating these new and exciting "sounds" which we cannot hear in real life, filmmakers must create their own interpretations based on how we imagine these space activities would really sound like.
Sound travels in waves like light or heat and by making molecules VIBRATE.
While the sound is an oscillating pressure wave, which propagates as a longitudinal wave in a classic material medium, it is not the same phenomenon in a vacuum. This is due to the fact that a propagation medium, as required by the acoustic wave equation, is absent in a vacuum.
However, there can be oscillations in a vacuum, and they are usually related to thermal or quantum effects. There is no sound in space, as sound requires a medium to travel, and in space, there is no medium.
The vacuum of outer space has essentially zero air. If you are sitting in a space ship and another space ship explodes, you would hear nothing!
Exploding bombs, crashing asteroids, supernovas, and burning planets would similarly be silent in space.
However, if you were an astronaut, you may be able to hear such things because spaceships are still subject to air pressure and a vacuum is far from it. It can also depend on whether you are in a spaceship, surrounded by humans and machinery that may produce different types of noises than without anyone around, or if you're out there all alone surrounded only by the sounds of what's beyond your spaceship.
But, two astronauts floating in space will not be able to talk to each other directly no matter how hard they shout!