More on a Mars mission

I hope no one is getting too tired of me, Mars and the moon. I am very
interested in this, and have put in quite a bit of time and thought on these
concepts.

My latest idea is to scale back that monstrosity I first proposed, the giant
spinning wheel. However, we don't just scale it back, we design it so that it
can be expanded. That is the key. I should know better. When I first
designed a lunar colony, I came up with a monstrosity that would have cost
quite a few trillion to establish, and I am not exaggerating. Then I realized
I had to come up with something that would be feasible financially, but that
could grow.

So our Mars ship should be the same way We decide just what we want the
mission to do, and compare that with our building capabilities. Once we have
decided on an appropriate compromise between mission objectives and the time
and effort needed to get it into orbit, we go for it. This one is almost
certainly not Mars and beyond, this initial ship will be Mars and come on home.
That is ok though. We have been building and launching more stuff as our
schedule allows, and by the time it is back we expand it. Maybe it can do the
solar system tour at this point, or maybe we have to go for another out and
back, but it is bigger and more capable. Each time it gets back to the
Earth-moon system, we add more to it.

I don't think my giant wheel is the right concept, although it might work. We
could start with just the hub for the initial mission. Then maybe for the
second one we add one or more spokes, and once those are all attached we start
on the outer wheel. The only thing I really don't like about this is that
once the wheel is finished, it will be hard to expand it further.

I think a better concept might be a cylinder. It can be designed to be
expanded in any dimension. The first one might be fairly short, and look like
an old fashioned film canister. We might be able to make it big enough to
rotate for simulated gravity, or maybe not. If it is not big enough, when we
expand we can add another level around the outside, and repeat as needed until
we have something big enough to spin. Once we have as much diameter as we
want, we can start making it longer, and the only real limit will be how much
mass we can propel at a reasonable acceleration. We can hope that our
propulsion methods improve as this ship grows.

When we design the ship and each addition, we want to keep in mind that
structure functions will change. What was once the outer hull might become
floor or internal bulkhead. It should be designed so that we can put in
hatches (probably gas tight for compartmentalization) to allow travel to
different levels and different sections of the ship.

The outside hull should be designed so that attachment of additions is
possible, but that does not seem too difficult.

--
Ferengi rule of acquisition #192: Never cheat a Klingon...unless you're sure
you can get away with it.