[inetknght]

> How is living in space meaningfully different from living in a submersible in the ocean (apart from the view)?

Just off the top of my head:

- different ability to re-stock

You could re-stock your submersible just about anywhere. You're going to have to do a lot more planning for your groceries when you go in space though.

- access to microgravity

This simply isn't available in a submersible. Microgravity provides some interesting manufacturing and biological capabilities.

- completely different pressure profiles

Combining different pressure environments in microgravity is particularly interesting to me.

- different instrumentation capabilities

It's not just the view -- the atmosphere plays merry hell with instruments when measuring the cosmos. And it does so in ways that just aren't relevant to underwater environments.