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excessive that completely negates the lower launch costs, I've noticed this about Zubrin before, that he seems to view orbital assembly as exceedingly difficult and to be avoided at all costs. And I don't think that ISS can rightly be pointed to as an example of the extreme expense of space assembly. ISS might well have turned out a bit cheaper with fewer Skylab-sized modules than more Shuttle-cargo-bay-sized ones, but I think the costs associated with the interminable delays and setbacks would have completely swamped that. and he may
have a point, though if we want to do anything extensive in space (like
space solar power) we need to learn how to assemble large things in
orbit. And that's the thing right there. He has no interest in developing the skills needed to assemble things in space economically because he has no interest in space, only in the surface of Mars. He doesn't need orbital assembly to do what he wants on Mars, therefore (like so much else)he views it only asa distraction from what we really should be doing. He also argued strongly that the greater number of flights
increased risk of delays and mission failure, which is certainly a good
point with the current climate of
stand-down-until-the-last-problem-is-eliminated; I would have thought it
would be less of a problem in a commercial marketplace with two or more
contenders, but anyway. That's how I would view it. It strikes me that alaunch failure on one of ten heavy-lift launches is going to be more of a disruption of a schedule than one offorty medium-lift launches. if on the
other hand a less vigorous program was planned, that medium-lift
vehicles would be a better approach than investing billions in
technology that would barely be used. It's reminds me ofa comparison Heppenheimer made between some 18th Century ship design (can't remember the name) that died out and the Saturn 5: both examples of a heavy hauler that appeared on the scene before the large market that could have sustained them was in place.