Gosh, I love revisionist history

Those of you who do know your history know that the space shuttle as it stands now was a product of both political and budgetary constraints placed on the entire agenda of NASA.

Even before man stood on the moon, NASA was having contractors (like Lockheed, Boeing, Martin, et al) do feasability studies for the next generation of lift vehicles. The plan was "shuttle, station, mars: by the 1980's".

What happened to the plan was that Congress got a good look at the projections of costs, and freaked out. They made NASA justify each step on its own, ie you could not justify a shuttle because it was needed for a space station; similarly, the need for a spacestation in any Mars project was no justification for a space station. So any Shuttle program had to justify itself.

Meanwhile, the contractors were playing with all kinds of plans, from the fully disposable (for example, a 6-person Apollo type vehicle) to the fully reusable (like the Trinoo, a three piece spacecraft that had three practically identical parts, two of which were boosters and a third which lifted people and/or cargo into orbit).

The distinction is important, because it dictates where your costs are. Fully disposable craft are cheap to design and expensive to operate (because you throw away the whole thing each time you use it and have to build a new one), while fully reusable craft are expensive to design (because reusability isn't easy) but cheap to operate -- because you can ideally just fuel the sucker up and go.

Now, if you are a Congress critter who has to get re-elected in the short term, which are you going to want to have? That's right -- smaller up-front costs. Let future Congress critters deal with the higher operational costs.

If you look through the history, the current incarnation of the Space Shuttle appeared very late in the process, and was designed to be a swiss army knife -- all things to all people. It was partly reusable (to keep operational costs down); it was partly disposable (to keep design costs down); it had a whopping big carrying capacity so it could carry all kinds of orbital payloads, including large military and large scientific payloads; and it kept much of the military contractors usefully solvent without having to hold an actual war.

The bottom line when it comes to any kind of technology project is: technology you have in your hand and can use today beats any kind of technology which is on paper. The second best kind of technology is that which the bean counters will actually let you buy and then hold in your hand. NASA needed another project, and the Space Shuttle got approved.

And let's not forget that the Space Shuttle has produced some of the most impressive engineering technology available today. Not only is a Space Shuttle Main Engine one of the more powerful rocket motors available, it is the only one which is reusable. Even if the russian Energia lifter is a more powerful rocket, it is a throwaway rocket.

While the Delta Star project had some interesting possibilities, it reflects the fact that Rocket Science is heady stuff. The aerospike engine design is exciting, and I'm sure it will show up somewhere in some form. And let's not knock the designers of these fuel tanks. Consider that the Delta Star would be the first craft to bring primary fuel tanks back through the atmosphere and expect them to be reusable again. Not a simple problem to solve.

When it comes to the future, I think that Mars should not be a priority. There's not much in the way of additional science to be done by sending people there than can be done by sending cheaper robots.

Is the techology present to send a man to Mars and bring him home safely? Sure. But the mission would end up being just as disposable as the Moon missions were. If we are going, we should plan to stay, and we have a whole lot more to learn technically before we can do that. Most importantly, before we've done some long term studies on the feasability of closed biospheres in orbit, it is a foolish idea to send off a Mars mission.

The big question for a sending a Mars is the 'And Then What?' This was the question that NASA really failed to answer, and sell an answer to, to the American public during the Moon missions. 'Because we can' is a stupid answer. 'Future population relief' just shows that the answerer can't deal with basic math or economics.

With all that in mind, I think the Space Shuttle is doing a remarkable job, and that the ISS is a good next step into orbit. Beyond that, there has to be more study on orbital construction, long term operation of a closed biosphere and living in such a space for a long period of time, and development of better engines for jetting around the solar system (sails, nuclear, ion, magnetic, whatever). Just about all of this will forward the need for a next-generation reusable lift device. And we should keep sending out robotic explorers everywhere we think we can get good data back from -- and a few places which are iffy.