4 ms·

Sorry if I wasn't clear, but I brought up the question of floating with respect to nitrogen/CO2 atmospheres (thinking Titanlike or Venuslike) not hydrogen.

• lisper 3y ago
  It's a moot point, but I still want to point out that "a gas lighter than hydrogen" is a thing: it is simply hydrogen at a higher temperature, i.e. a hot-hydrogen balloon, analogous to a hot-air balloon.
  • thfuran 3y ago
    Well, maybe if there's no oxygen nearby.
    • lisper 3y ago
      If you have a planet with a hydrogen atmosphere, it's a pretty good bet there is no (free) oxygen nearby.
      • thfuran 3y ago
        Fair point
  • simcop2387 3y ago
    I do not want to ride in a hot hydrogen balloon :)
    • eru 3y ago
      Why not? Hydrogen inside a hydrogen atmosphere is perfectly safe. It's hydrogen inside an oxygen atmosphere that's the problem. (So on Jupiter, you wouldn't want to ride in an oxygen balloon, ie you wouldn't want to ride in a hot air balloon there.)