Soundless Space: Astronauts' Silent Communication

Listen to this. Astronauts can't actually talk to each other in space the way you think

they do. Sound needs air to travel, and space is a vacuum. So when astronauts

are floating outside the station doing repairs, they rely entirely on radio communication

through their helmets. Without those radios, they could be face to face and wouldn't hear a single word.

Two people separated by just a thin layer of glass, completely silent to each other.

Space really is the ultimate soundproof room.