Yeah. I think that they are simplifying a bit. For practical purposes, for the foreseeable future, it is a “can’t be”. There is a lot of work and research that would be necessary to get an orbital shipyard in place. As someone else mentioned, the current state-of-the-art space station is effectively little more than rocket body segments with extras (solar panels, etc).
It’s much easier for me to say “this is what we would need to do” than to actually do it. We have the technology to build a space station. We don’t currently have proven technologies to refine, cast, forge, and extrude metal in microgravity and hard vacuum. We don’t currently have proven technologies to manufacturer space craft out of components in microgravity and hard vacuum. And those are just a handful of the necessary things that we know - there are a bunch of unknown unknowns.
So, technically, yes, it isn’t a “can’t be” but, at this time, it may as well be.
My company worked on the ISS (what’s now my team did the electrical power system software), and there really was more to it than that. The way you word it sounds like they took spent boosters and converted them into habitat modules, but that’s not at all the way it was. Each element was designed to be brought up in the space shuttle bay and assembled in space (it’s the reason for the shuttle’s existence). We know how to assemble stuff in space, it’s just expensive.
Assembling premade components is one thing, I think he was talking about actually making stuff. If we want effective shielding, that’s a lot of mass, so it would be much easier if we could find it already up there
Definitely oversimplification and I don’t mean to understate the efforts, technology, engineering, and materials that went into the ISS. It’s incredible. My main point being just how simple the current state-of-the-art is compared to what would be needed for a sustainable orbital shipyard.
We know how to assemble stuff in space, it’s just expensive.
Indeed (ISS being a good example of this fact). The scope here though is beyond just assembly. Also, at minimum, manufacturing of shielding components would likely be necessary in order for such an undertaking to be feasible.
