At the peak of the Space Race, both the Russian and the United States space agencies were developing plans to establish permanent space colonies in orbit around our planet and beyond. In fact, in 1975, NASA’s Ames Research Center gathered 19 professors at Stanford University for 10 weeks with intention of not only designing what a human space colony would look like, but also figuring out how these systems might function as self-sufficient, long-term human outposts. The team of researchers was given a theoretical budget of roughly $35 billion dollars (or about $200 billion in 2017 when adjusted for inflation) to create these apparatuses.

While these massive structures may seem straight out of vintage pulp fiction, these colonies were well within our technical and engineering capabilities 40 years ago, and it’s even been argued that a series of such permanent colonies could be readily constructed for less than what the U.S. spends annually on its military.

The Ames Research Center studies concluded with three main design concepts: The Bernal sphere, the O’Neill cylinder, and the Stanford torus. While each design has its own unique structural shape, they all rotate to create a centrifugal force to induce gravity for inhabitants inside. Once constructed in-situ, these colonies would revolve around the Earth in the same orbit as the moon in a sliver of space between the Earth and moon known as the Lagrangian libration point.

At the time of these proposals, NASA had just launched the Pioneer 10 probe carrying a “interstellar greeting card” to grant salutations to any extraterrestrial life too haphazardly drifting through the cosmos. It wasn’t so long ago that the future of extended manned space exploration and colonization never seemed more feasible. In just 14 years mankind went from hurling the most rudimentary of satellites into orbit to quite literally teeing off on the moon using a makeshift six-iron — a true testament to the ingenuity and boundless curiosity of our species.

Unfortunately, more than 40 years have passed since this conference and unfortunately we are still without a drifting Logan’s Run-esque colony glinting in orbit or even the most primitive of terraformed bubbles. Perhaps this will change in the near future — especially if Elon Musk has his way. Whether we ever actually leave this space rock and become a multi-planetary species is anyone’s guess. Only time will tell…