New Mars Forums

The relationship you imply, big booster=simple spacecraft, small booster=complex spacecraft, does not exist.  Any mission to Mars or anywhere else for that matter is going to require a number of different spacecraft and boosters.  Look at Apollo - from Earth orbit you have SV third stage, LM, CM and SM - four separate systems.  The only difference between HLLV and DIV Heavy is whether you launch them together or separately.  (Ok, a delta IV would be struggling to launch the saturn third stage in one throw, but the way you would do a moon landing with EOR or EML1R is sufficiently different that you wouldn't be using a TLI booster sized that big in any case)

I favour the delta and atlas approach because then NASA can just go and buy launches, and does not have yet another very expensive launch vehicle development that it can stuff up.  However you look at it, NASA has to develop the CEV.  No CEV, indeed no spacecraft, is going to be simple, so NASA's going to be struggling to do a good job of that.  Shoulder it with the distraction of having to build a new HLLV (and a shuttle derived vehicle is  still a new vehicle - shuttle components are not leggo) and you are (IMHO) setting them up to fail.  Besides which, you then have two big vehicle development projects going on simultaneously - with both driving requirements for the other, and that's just asking for trouble.

The conceptual simplicity of Mars Direct is just that - conceptual.  The basic concepts of a safe haven on Mars, prepositioning hardware and ISRU are excellent and should be part of any architecture, but as for the rest eg HLLV - that only looks simple.  The devil is in the detail, and asking NASA to build an HLLV now is a brute force solution to a problem that calls for elegence.  It's not necessary, it can't be justified economically, and it would likely tip NASA over the edge.

Cheers,
Rob.

Michael,

The ISS is not really economically effient, nor has is displayed really good science, and yet more billions of dollars have been spent on it than really bears thinking about.
The same is true of the shuttle.  Bush's plan in any case is not justified by science, but by exploration.

Nasa is exactly about factualizing science fiction - what do you call flying people to other planets?  I get your point that it's not about building the Battlestar Galactica, but can you tell me what is wrong with multiple launches and on-orbit rendesvous/docking?

As for the comparison to columbus, passion will not help a crew of mars explorers breathe vaccuum if their life support fails six months from Earth because its a brand new design that hasn't already clocked up several years of operational experience in space.  Columbus already had all the experience he needed - he knew how to sail his ship, and how he could expect it to perform.  I'm not saying we should stay at home until somebody invents the warp drive, and I agree with you that a Mars mission is completely possible with chemical propulsion and technologies that we have in hand - I'm just saying that some operational experience with those technologies would be a good thing before we commit a crew to a three year mission.  We don't need a HLLV to get that experience, and we probably dont need one to go to Mars.

The point is, if you are really serious about seeing people on Mars (I'm sure you are, and so am I) then you should be prepared to wait an extra few (five or less) years while we carry out some prudent rehearsal missions.  The moon is a reasonable place to carry them out, and while we are there we should take advantage of whatever that location has to offer in terms of basing of telescopes, ISRU, or whatever.

Why do you feel we have to go to Mars exclusively and ASAP?  So long as Mars is the stated goal, and in a reasonable timeframe, other preparatory work at L1 or the moon is IMHO a good thing, that only makes planned Mars missions more robust and realistic.  Are you worried about the rehearsal eating up all the money for the real mission?  You should be more worried about sprinting off to Mars without adequate preparation.