For a spacestation to grow enough food to feed 3 people would require an arable surface area of 15 hectares (37 U.S. survey acres). If we use the same structure as "Starship Generations" with many nested cylinders enclosed within a sphere then we get some challenging results. Allowing 3 meters (9.8 feet) between floors, and a central cylinder of 6-meter diameter, then this orbiting greenhouse would require 23 nested cylinders (graduated lengths & diameters) with a maximum diameter of 138 meters (453 feet), all enclosed within a spherical shell. This structure would have to rotate at 3.6 rpm to achieve full gravity in the outer cylinder, and the coriolis effects would be debilitating. Therefore keeping the rotation at 1 rpm or less means that a maximum of 0.27-g's could be achieved in the outer cylinder and less gravity nearer the rotation axis.

Is this really possible with NASA's budget?

Here's another question:

If we intended to manufacture things in space, then we would have to "qualify" them as well. Could NASA equip a space station with internal thermal-vacuum and anechoic test chambers? Would these be necessary?

For example, without the above facilities, how would you manufacture & qualify a new module for the space station, eg for air leaks?

Forget farming - build anything from space-based materials, and qualify it for use - that would be challenge enough! Don't you think?

Starship Generations