[ExI] cost of SBSP and thorium

[spike]

>... On Behalf Of Keith Henson
...

>...There are sound engineering reasons that a few pounds by itself will
always be expensive.  It's like the difference in transport cost between a
FedEx letter and a trainload of coal.  Keith

Another example is that the cost of delivering a single gram to LEO isn't
all that much lower than the cost of delivering 100 kg, if you are needing
specific orbit parameters.  It is well above that before the cost starts to
scale proportional to payload.  This assumes away of course the getaway
specials they used to have when we had a shuttle, which were one kg class
payloads.  I don't know if there is anything analogous to those
opportunities today.

spike