An essential piece of the progress of science and knowledge is being able to vary one parameter, while holding others constant, and just seeing what happens. "Turning knobs", to use a phrase Douglas Hofstadter put to a similar use. In principle, working in space should allow us to turn a variety of knobs that are either impossible or impractical to do on Earth - gravity is the obvious one; but also the exceedingly high vacuum, unusual radiation and thermal environments, dealing with unusual chemical and material surroundings. Genetic experiments could be sanctioned that would never be allowed on Earth. And so on.

Technology also progresses when we find a solution to a problem in a new domain; something with a few knobs turned differently, and then realize the implications of our new, more general solution, in new products back home. The arts, sports, business dealings, all can be changed profoundly in having to deal with a new environment. Out on the 'artemis-list' discussion group we had a recent question about how a waterfall would behave on the Moon - which led to queries about lunar snowflakes and precipitation, handling of waste water, etc. etc. There is so much that would be different it is hard to even think of all the issues just sitting here on Earth. No robot of the next couple of decades at least is going to be capable of going there and innovating in the way a human being can.

But what that means, and the ISS and Mir and Skylab prove, is that we are not going to get the kinds of innovations we could potentially get with just 3 or so people up there; we need hundreds or thousands of people, university campuses, research institutes in space. And we need to make getting into space cheaper and more reliable. Maybe China can show the way there...