>>13712898>Seriously, it's way easier to keep a cave sealed than constantly have to worry about saltwater corroding the hell out of metalPossibly, but transporting supplies to an ocean habitat is going to be a lot easier than resupplying a Mars colony. And escape/evacuation, in the event of disaster, is much easier when a breathable atmosphere is minutes away.
That said,building underwater is dumb -- as is, at this point, seriously talking about colonizing Mars (let's maybe go there once, see how that goes, then we can talk colonization). In the meantime, anybody wanting t practice for Mars colonization can build a self-sustaining colony in Antarctica, where water is plentiful, oxygen in the atmosphere is plentiful, nitrogen for growing plants is plentiful and, best of all, it is currently technologically possible to move supplies to build you habitat there. That's about a million times easier to do than Mars, but it would be good practice.
