Reposting my space colonization plan here for critique, other thread is dead:
**0.** Establish an Equatorial Launch Ring. No, not that sci-fi nonsense you are probably thinking about. What I mean is a string of launch platforms on the equator, around 150 of them encircling the Earth, spaced ~250 kilometers apart. Then have SpaceX style reusable methalox rockets continuously hop around the ring in the direction of Earth rotation, launching payloads with every hop and landing on the next platform to be immediately reused again. It should be possible to cheaply orbit hundreds of thousands of tons of payload per year with this system. No need for RTLS also increases payload mass and reduces wear on the engines. Optional upgrade: use carbon neutral nuclear power or renewable electricity to manufacture propellant (oxygen and methane) directly at the launch pad, from seawater and CO2.
Another crucial step is to develop closed loop life support systems that can function almost indefinitely with the only input being energy. This should be possible because there are sealed bottle gardens thriving for over 50 years and counting. Biosphere project also worked well after initial problems were solved, and failed mostly due to crew conflicts, not the technology.
**1.** Build large spinning (for gravity) space stations in equatorial low Earth orbit. It is the only place where galactic cosmic rays are significantly reduced due to our magnetosphere, while at the same time with low inclination to avoid radiation from the South Atlantic Anomaly. This leads radiation levels that almost approach Earth-like ones, in space! Coincidentally, it is the easiest orbit to launch to from Earth. Some prime real estate indeed.http://space.alglobus.net/