6

I'm working on a science fiction piece set on Enceladus, and I'd like the characters (human) to do a fair amount of swimming (they've managed to terraform a small bit of ocean for themselves). However, since the phase velocity of the wave would be greatly reduced, as pointed out in the swimming on Mars post, I'm wondering if swimming in Enceladus' .113G would be feasible at all, or if there might be a more desirable means of moving oneself across a body of water in extreme low-G scenarios.

uhoh
  • 148,791
  • 53
  • 476
  • 1,473
adamholtwrites
  • 241
  • 2
  • 7

1 Answers1

6

Sure. Whatever the pressure-based limit is, they can dive proportionally deeper by the amount that the gravitational acceleration is less. For Enceladus, that would be 87 times deeper. The pressure is simply the weight of the water above you, and the weight is proportional to gravity.

The pressure-based limit on Earth depends on what effect you are worrying about. If it's nitrogen narcosis, it's about 30 meters. If it's oxygen toxicity, because you've mitigated nitrogen problem by reducing the nitrogen but increased the oxygen, it's about 56 meters. To go deeper you add helium to the mix to reduce the oxygen partial pressure. Then the limit is around 300 meters.

So multiply those by 87.

Or there is no limit, except that due to materials strength, if you build your own pressure chamber.

Make sure you bring a lot of light.

Mark Adler
  • 58,160
  • 3
  • 171
  • 251
  • 1
    By the way, the ice above the water is part of the weight generating the pressure, so you'll need to account for that as well. – Mark Adler Feb 23 '16 at 21:15
  • Quite helpful, Mark. I'll have to look into the lunar swimming to see what other issues arise there. Wave height is of interest to me as well. With so little gravity, I'm imagining notably peaky, narrow waves, too. PS - we will bring lots of light. – adamholtwrites Feb 23 '16 at 23:01
  • Is there anything like a similar limit for the bends? Like below X meters there is no significant risk at least? Needed for this answer. – uhoh Jun 29 '16 at 15:54
  • Multiplying 300 meters by 87 gives 26 km or thereabouts. Do we run into rock? – Oscar Lanzi Jul 03 '19 at 20:55
  • 1
    @OscarLanzi No. Europa's ocean is estimated to be 60 to 100 km deep. – Mark Adler Jul 03 '19 at 22:37