Tags Dr. Kelly Weinersmith future of humans in space space settlement space tourism radiation concerns GCR radiation concern microgravity on the job training for human space medical factors chimps and animal experiments why leave Earth backup plan for Earth disaster protecting Earth SpaceX Mars Earth independence Mars government lunar private sector habitats He3 lunar mining the true believers among us overview effect utopia believers Overview Effect interviewee follow up interview surveys without bias determining the gravity prescription ISS research bone loss concerns mitigating protocols for microgravity deterioration in-orbit centrifuge fusion energy Nuclear propulsion VASIMIR Virgin Galactic Blue Origin SpaceX Inspiration 4 orbital flight FAA astronaut wings change in requirements Mars simulations Skylab simulator nuclear submarines as Mars analogs CO2 problems psychological problems public vs. private sector space settlements uncertainty and risk FAA rule change for Guest Dr. Kelly Weinersmith Tagline Dr. Weinersmith's study and upcoming book on space tourism View the discussion thread.