Critical time

Date: Thu, 5 Apr 2001 11:14:26 -0500

OK. But if a mass-driver launched sufficient mass to build 5 Island
3's
over its operational lifetime, that would be around 5 billion tons.
How
many individual kilogram launches would that be? If we amortized
construction & infrastructure costs, how finely-divided would those
costs
wind up being?

Regards,
Mike Combs

You're still not included all of the infrastructure launch costs involved in
setting up the mass drivers & making them useful in the first place (after
all, there's no point in building the mass driver if you don't build the
mind to go with it) or against cost mitigation strategies for less overtly
technological solutions (such as direct launch from Earth &/or in situ
tunnelling construction); & modelling the numbers to make a mass driver make
financial sense isn't easy. It's like the argument that we need to mine
asteroids for fuel in order to fly to Mars (i've chosen a particularly dumb
eg of the argument to show its fallacies) - this obviously only makes sense
if the total cost of the mining operation is less than merely thumping the
fuel up from Earth. There's been a recurring nightmare in space exploration
where large fortunes have been spent in developing technology to the point
where you no longer have any money left to fly the actual mission (NASA's
Halley fiasco & subsequent failure to deliver the key solar imaging system
to Ulysses are good egs of this; as are the multiple attempts to cancel
Pluto-Kuiper Express to pay for vaporware research on Europa Orbiter). If a
mass driver is useful for a Lunar base, it MAY act as an enabling technology
for a non planetary platform; but building it in to the requirements of such
a platform increases complexity, cost & the range of options which can go
wrong.

All the best,
Robert Clements Robert.Clements@...
endeavour2 project http://www.geocities.com/robtclements/endeavour2.html>