The sound effects in the podcast Moon Graffiti help transport the audience from being a passive listener to feeling like they are a part of the story. The sound effects help create the atmosphere that is envisioned by the creators to impart a sense of urgency and increasing fear as the podcast episode continues. It creates a sense of anxiety in the listener as they envision being stuck on the moon with the astronauts.
There are only a few moments of true silence in the entire episode. The constant sound makes the the silent moments stand way more and gives them much more importance than if the entire episode had just been dialogue between the astronauts.
From 12:00-12:10 in the episode the sound effects that accompany Buzz’s slight delirium really help the audience understand the emotions that he might be feeling. The static heard near the end help drive the point home of the silence of both astronaut’s forever.