It is irritating to hear claims that something can be done which has never been done. Hardly irritating - that's my job, which I enjoy. Sure, moon colonies wo

It is irritating to hear claims that something can be done which has never been done. Hardly irritating - that's my job, which I enjoy. Sure, moon colonies would require enormous effort, staggering cost, and some new technology. The problem isn't the engineering challenge; we put people & equipment in a habitable box, and brought them back, using half-century-old technology. The problem is the cost far exceeds the payoff for anywhere close to the foreseeable future, and the scenery there is about as interesting as Death Valley (briefly compelling, but you wouldn't want to live there).