Digest 1105 Msg 7

I think this is the correct way to view this: Firstly, we can all agree that building orbital habitats to build orbital habitats is begging the question. It's the same circular logic (and fatal flaw) in the Mars settlement promoter's scenario; that we're going to build settlements on Mars because we're going to economically develop Mars which we'll need to do to support all those settlers coming to Mars. The infrastructure to mine the moon and/or NEAs, transport ores to HEO, refine ores to pure elements, and fabricate components will initially be built up in support of SPS. At the beginning,workers will live in spartan quarters comparable to those on off-shore oil-drilling platforms. Frequent crew rotations to Earth are necessary, but expensive. The first space habitat will be built largely to house space construction workers and their immediate families. These space workers will, for the most part, stillbe building SPS. Once the first habitat is built, a second one can be built for around an order of magnitude smaller investment. Bring that down by another order of magnitude, and one might sensibly start talking about building habitats for sale toimmigrants from Earth and making a profit at it. SPS expands to the point where it's a significant (perhaps the most significant) contributor to new electrical generation capability. However, a few decades down the road, SPS manufacture begins to ramp down as capacity approaches demand. On the other hand, the demand for additional habitats for space settlers continues to climb, as manufacturing costs decline due to economies of scale, andthe market moves from the well-moneyed variety of clientele to a much broader market of peoplewho may wantto leave Earth as much for political reasons as for the superiorliving conditions. Past a point, space construction workers find themselves spending more time building new habitats than new SPS. From that point forward, habitat replication becomes the primary activity of orbital habitats.

Regards,
Mike Combs

Personally, I'd put resource extraction ahead of manufacturing.

1> Solar satellites
2> Asteroid wrangling for platinum group metals, or possibly He3
3> Comet wrangling for volatiles

I would expect that only excess capacity would be used for building
new colony components.