Artist Don Davis has been commissioned by NASA to paint real and imagined visions of outer space since the 1970s. He released a number of these works into the public domain in 2007. Amongst these are a series of speculative paintings (see accompanying images) of future space colonies produced in the mid 70s. This was an era when the idea of space colonisation was being seriously considered, led by Gerard K. O'Neill at Princeton. O'Neill asked the students of his physics class to consider the question "Is the surface of a planet the best place for an expanding technological civilisation?" and so instigated a train of thought leading to the examination of the practical implications of orbiting space colonies and ultimately this detailed series of paintings by Don Davis.