Going undersea requires a much more robust design. Pressure does horrendous things to technology.

The objective is to provide an analog close to space where the consequences are really life and death, … Rookies can make their mistakes before they get to space.

The state of technology (for undersea exploration) is still in its infancy, … We have 90 years and two countries’ worth of experience in space exploration — and maybe a dozen real serious underwater habitats....

We’re operating very close to the conservative end of undersea habitation. The challenges go up exponentially as you go deeper.