Back in the 1970s, NASA commisioned some studies of space habitats. From this research we got Gerald O’Neal’s famous “Colonies in Space” book as well as engineering design studies from several major universities. In order to visualize some of the designs, they commisioned some artists to show what they might look like. Here are some of the better images:
http://www.nas.nasa.gov/About/Education/SpaceSettlement/70sArt/art.html
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