Inspired by the question Can fish really live in microgravity without water? I got wondering. If I lived in zero G, could I have a dolphin for a pet? Dolphins (and whales) breath normal air just like people, the two biggest reasons reasons they must be in water is for support and movement, neither of this would seem to be significant issue in zero gravity. Assuming skin moisturization is addressed (and given sufficient area), is there any reason a dolphin (or whale) could not swim and survive just fine in space?
Your main problem is that dolphins breathe air. Normally they come to the surface or even jump out of it and take a breath before submerging again.
How will they do this in space?
- If you have a large capsule full of water, there will be no air.
- If you add in some air, will it stay in one place, or in one large blob so that the dolphin could breathe it? Or would it split up into bubbles each time your hapless pet swam around?
- If you have a very large ball of water in the middle of a larger sphere (and work out how to keep it from touching the sides and adhering) a dolphin could jump through the surface tension, take a breath, and...hit the side of the capsule!
- Maybe have a cylindrical capsule and spin it to provide centripetal force to 'stick' the water to the sides so the dolphin could jump. That would work, I guess.
- Or fit Flipper with SCUBA gear? Little bit extravagant though - how about a fish?
If you want instead to keep the dolphin in air you would need to sort a different range of problems, including how to moisturise their skin, provide them enough water to drink etc., but really the main issue will be protecting them from the major injuries they will incur when bashing into the walls all the time as it won't be able to change direction in air.
Dolphins require water to push against to swim, but that would be the only problem.
The dolphin might panic and thrash around like a fool at first, but would eventually adapt. The other problem might be crashing into things thereby injuring the dolphin, if the dolphin could move at speed at all.