Alain Fournier wrote:

:Fred J. McCall wrote:
: "Paul F. Dietz" wrote:
:
: :Nonsense. Many many things have become affordable because
: f advances not specifically directed at those things.
:
: If you think it's nonsense, please tell us just what technologies you
: think are sufficiently 'dual use' to Mars flights and something else
: (and what that something else is) so as to drive down the costs of
: Mars flights.
:
:
:New stronger materials (a dual use, airplanes and others), electronics
dual use home computers and others),

This doesn't NECESSARILY drive down costs. I seem to recall that a
decade and more ago some folks arrived at the conclusion that using
swaged steel for the body of an expendable launcher was more
economical than using more exotic materials that would be stronger and
lighter.

:fuel cells (dual use cars and
thers) etc.

I believe we've had the sort of fuel cells you'd want to use for a
spacecraft for a long, long time. The ones for applications like
automobiles are somewhat different.

:That is not even mentioning more directly related dual uses such as
:satellite launches and space stations.

The sort of 'space stations' we're doing now don't do anything for a
Mars mission so far as I can tell. I don't see a lot of progress in
satellite launches.

Launcher advances would be lower cost of getting mass into orbit. So
far there are not any large signs of huge advances in this area.
Given the current trend-line, it's going to be a long, long time
before this drives far enough to really help much. The question
arises of just what will drive launch technologies to lower costs.

--
"Millions for defense, but not one cent for tribute."
-- Charles Pinckney