Space Is Completely, Perfectly Silent

If you've watched any space film, you've heard explosions rumble across the void. Engines roar. Lasers hum. All of it is fiction.

Sound needs something to travel through: air, water, even solid rock. Space has none of these. It's a near-perfect vacuum. If you stood on the Moon's surface and someone clapped right next to you (without a spacesuit radio), you wouldn't hear a thing. You'd see their hands move. Nothing else.

This is why astronauts on spacewalks talk entirely through radios. The gap between two astronauts floating a metre apart is, acoustically, infinite. That one took me a moment to sit with, honestly. A metre away from another person, and the silence between you is total.

Next time a space film rattles your speakers with an explosion, you've got your correction ready.

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