These questions are about a fictional space station in my novel. Just a little background, the station itself is modeled on an expanded version of the “Kalpana One” proposal (pdf here if interested) which was developed by the American Institute of Aeronautics and Astronautics. The Kalpana One is a cylinder with: Radius (R) 250m Length (L) 325m Angular Velocity (Ω) 2.0 revolutions/minute Centripetal Acceleration (A) 1.0 G Population ~3,000 people Question 1 – Can you offer a suggestion on how to increase the dimensions to facilitate a population that is roughly 1,000x bigger – for a final population of about 3 million? Having the final length and radius will help me develop a layout of all the important settings. I’ve found calculators (such as http://www.artificial-gravity.com/sw/SpinCalc/SpinCalc.htm) but they don't seem to allow me to calculate expansions in length and radius alone while keeping the needed variables constant. And I am assuming I can’t get away with just multiplying the radius, length, population, etc. by the same value. I just don’t have the level of mathematical understanding here to really know what figures might seem plausible or at the very least (my true goal here) not seem completely ridiculous to a reader. Question 2 (now this will seem like a very dumb question, I apologize) – Would a station of this size (both the original and increased size) have to orbit a planet? Or could it theoretically be placed at an appropriate length from a star on its own? In my novel, this station is in a foreign star system (not in our solar system). In this regard (not in direct orbit around a planet or planetoid), it is similar to the Citadel from Mass Effect. From the .pdf on Kalpana One: “Although the design is not orbit-specific and is intended to be replicated many times, and expanded, the first Kalpana One orbital settlement may be built in an equatorial Low Earth Orbit (LEO) at an altitude of approximately 600 km or so; high enough to avoid rapid entry into the Earth’s atmosphere and minimize reboost requirements, but low enough for the van Allen Belts to provide radiation protection to reduce shielding mass.” Unfortunately, I again do not have the physics and mathematical background to know all the variables that might or might not make such a thing plausible.