Those of a certain age and a certain bent can't fail to look at this beautiful depiction of the interior of a space station without a sense of nostalgia. Because, though Don Davis (in this case) depicts a presumably far-future vision of human space colonies, the art itself is very much of its time: the 1970s.

It's easy to mistake as being conceptual art for speculative fiction, but in fact this image, and the others here, come about as a result of successive summer studies from the collective brains of NASA, Princeton and Stanford. Here's some of what they came up with.