In case you were thinking of writing a story in which your characters are talking in the thin atmosphere of Mars, think about this:
The work, which was presented at the Lunar and Planetary Science Conference in Texas on 8 March, also revealed that the sound travelled in an unusual way in the Martian atmosphere, which is primarily low-pressure carbon dioxide. On Mars, higher frequency sounds arrive before the lower bass ones due to the way CO2 molecules vibrate differently at low and high frequencies.
“You would receive all the low frequencies of my voice a few milliseconds after the high frequencies… so it would lead to a kind of distortion of sounds that would be quite difficult to understand,” says [Baptiste Chide at Los Alamos National Laboratory]. [NewScientist (19 March 2022, paywall)]
Always some nasty Law of Nature to invalidate your beautiful story. Or maybe you can only talk in mostly nitrogen atmosphere.
