Stanford Torus vs Bernal Sphere

I think the question you're trying to ask is, "All other things being
equal, which is more efficient of building material, a sphere or a
torus?" I think the answer is "sphere". I think their heightened
concern about rotation rates may have caused the Summer Study group to
go with a greater radius (1.1 miles) than they might have otherwise.
Not being able to back away from the fixed, large radius, they then
tried to minimize structural mass by going with a torus shape. But the
Torus takes a big hit when it comes to the mass of the radiation shield.
The sphere shape represents the greatest volume enclosed by the smallest
surface area.

Right, that's exactly what I meant. Since you say a sphere is more
efficient of building materials, can you give some sort of an idea about
what would be the difference between the structural mass of a sphere and
a torus (of course, keeping all other factors constant)?

Thanks once again and regards
Saatvik Agarwal

Combs, Mike wrote: