Imagine you could sing on Mars. Even if you did it in your best voice, it wouldn’t sound the same as it did on Earth, and no one would probably recognize you if they could only hear you. The reason lies in the nature of sound: it is a wave that depends one hundred percent on the fluid through which it travels, in this case air.
On Mars, that fluid is very different. Its atmosphere is ninety-five percent carbon dioxide and is one hundred times less dense than ours. Therefore, even if the same sound came out of your vocal cords, with the same timbre and intensity, it would not sound the same to whoever listened to you. What changes is not how you emit your voice, but the medium that transports it to your ear.
This is not just theory. As measured by the Perseverance rover, on Mars sound travels slower and the highs are muted. The result is that your voice would sound weak and muffled.
On Venus the effect is different. There the pressure is overwhelming and your voice would become cavernous and deep, as if you were speaking inside an underwater tunnel.
Santiago Campillo (@Scruzcampillo) is a biologist and scientific communicator specialized in health, nutrition and nature.
