In outer space you could see a distant explosion (separated by space), however you would not hear the explosion. Explain why this happens based upon your knowledge of wave propagation.

Think about the wave propagation of sound. How does it work? What does it need to work?

The space between the explosion and you is a vacuum, meaning it is completely empty. Why, therefore, will sound not be able to travel through it?

Hint: think about wave propagation and compression.