In the human race’s distant past, the world was effectively boundless. The L5 Society was originally founded on the vision that it’s possible to recreate early man’s boundless world. Unfortunately, we now know that space is filled with a sleet of deadly cosmic radiation, from all directions. To settle outside Earth’s magnetic field will require living behind permanent shielding 6 meters thick in each direction. Fortunately for humanity, we have the Moon right on our doorstep, which can provide nearly all the basic requirements for self-sufficient space settlements of tens or even hundreds of millions. There remains a critical problem: For two weeks out of each month, the Moon’s surface sees no sun. The Sacramento L5 Society has uncovered a practical solution to that problem based on clean, bountiful solar energy.