Explained, by Jeff Greason (it’s buried in the comments, so I thought I’d post it up front here):
A little disappointed in the debate above.
I’m going to try, one more time, to explain flexible path. It isn’t hard. You just have to read what we said rather than try to do Kremlinology on what you think we must have meant.
I’ll boil it down the same way that I explained it to policy makers.
* We want to go to Mars.
* We can’t reasonably go to Mars without more experience with long-duration missions.
* Long-duration missions can be done to Lagrange points, NEO’s, and Phobos/Deimos and they are all worthwhile missions in their own right.
* We can’t reasonably go to Mars without updating our experience doing manned planetary exploration.
* Manned planetary exploration would be done on the Moon, which is a worthwhile mission in its own right, and could be a source of propellant for exploration.
* The Moon vs. Mars vs. NEO’s is therefore a FALSE CHOICE; the only choice we have is what sequence we do them in.
* Therefore, the only reasonable way to proceed is to accept that we MUST plan to do all of these things and plan accordingly.
* Since the spacecraft, lander, and boosters/EDS’s are the expensive part, constrained budget says develop 1 or at most 2 of them first.Now, the version of this in the Augustine report was:
* Do the boosters/EDS’s and spacecraft first
* Do buildup flights in LEO, Lagrange, Cislunar, NEO’s
* Do Lunar landings
* Do Mars
(whether Phobos came before or after Lunar landings really wasn’t clear, it depends on how the technologies shake out).Look at the mission timeline in the report, under flexible path, and you see Lunar landings, NEO visits, and Phobos visits before Mars. Construing that as “abandoning the moon” or “don’t touch” requires one to either refuse to read the report, to assume we only meant part of what we said, or to be dishonest.
Today, as it seems the NASA budget may not support doing 2 elements at once, I would suggest we do one at a time:
* spacecraft
* then boosters
* then landersBecause that way we can begin the exploration sequence with spacecraft on existing boosters and build the (relatively modest) upgraded boosters we need for more agressive missions as we go.
Makes sense to me. But the “look but don’t touch” morons will continue to be confused. I’m sure that we’ll be discussing this this evening, on a panel on which Jeff and I will be on, at the conference.
We want to go to Mars.
Why? Explain your first point in a way that will convince a nation to spend hundreds of billions of dollars to put a human on Mars.
Without the first step explained, the rest of the argument falls apart.
Why? Explain your first point in a way that will convince a nation to spend hundreds of billions of dollars to put a human on Mars.
What happens if it doesn’t cost hundreds of billions to put a human on Mars? What happens if it costs billions of dollars? Reducing the cost of BEO missions is one of the things that I think needs to be worked on. Otherwise we’ll be stuck with dilemmas like the above.
OK, Karl, then the corollary becomes: explain why a human Mars mission might be only expected to cost a few billion dollars instead of hundreds of billions of dollars, and whether those compromises (one-way trip, for instance) are compatible with the original goals that motivate the pursuit (national pride, etc.)
What the “look but don’t touch” people want is a big box in wrapping paper with a bow on it. Open it up and it’s a complete “We’re Going to Mars!” kit. Very expensive – use only once.
What the “flexible path” folks propose is several boxes of an Erector set that can be purchased one at a time that builds the tools for manned exploration of the inner solar system. Affordable and can be used many times. Why is this harder to sell?
Having debated on several occasions with the “national pride” folks on several web sites it sure seems like spending great gobs of money on space is intrinsically part of what they want. It’s as though the easiest way to prove that nobody but the U.S. can do space travel right is to make sure it costs more money than any other nation can afford. If you can show that it only takes a few hundred million dollars to develop a medium lift booster and a human rated capsule (e.g. SpaceX) then all of a sudden it’s not much to boast about — or so they think. My take is that our innovative society and our dynamic economy are what we can really be proud about — and nobody else is even in the same league with us.
Jeff has “explained” this before. In contrast to his suggestion that we’re all too dense to comprehend it, the simple fact is that many of us do not believe that it will happen.
NASA is not organizationally capable of executing a multi-decade technology research program ending with the building and use of real flight hardware in the absence of a specific goal, destination or time table. They have never done so and they will never do so. If they get $5-6 B per year for a decade for “exploration”, it will ALL be spent on paper studies, road-mapping exercises and managerial retreats and not on flight hardware or missions.
The “Mars is the ultimate destination”-mantra the Augustine committee adopted is unnecessarily limiting in that all space activities must be judged as to whether they are relevant to that goal or not. There is much to be done in cislunar space and much of it is not directly relevant to going to or landing on Mars. Human Mars missions are only one part of what we want to do in space; our real goals are to be able to go anywhere we want to conduct whatever activities we choose. In other words, the goal is to become a true space faring species. The emphasis in the committee report on “public engagement” and a “series of interesting “firsts” betrays the true mindset behind it — stunt missions and public spectacles that may or may not leave any lasting space faring capabilities and infrastructure.
We understand the Flexible Path perfectly. That’s why some of us think it’s a bad idea.
Paul, but as I’ve said to you before, the problem is that more often than not you mischaracterize what Flexible Path is, rather than faithfully describe what the intention is, then describe why you disagree. Jeff doesn’t care if you disagree, he does care that you seem incapable of articulating what you’re disagreeing with.
“betrays the true mindset behind it” – you’re a retard, seriously Paul. WTF?
Oh, and I note that you’re can’t ban me from this site like you have on your blog, fascist.
NASA is not capable of conducting multidecade R&D projects. Period.
Voyager QED.
The flexible path plan makes complete sense to me. It also includes in the finer details that goal that Paul Spudis is recommending. For instance, it includes the development of fuel depots, which is one of the most important enabling technologies to become a space faring society.
It is also definitely not a series of “stunts.” As Jeff keeps stating, it’s a series of necessary steps to gain the experience needed for going to Mars or any other distant destination. We need to be able to learn how to venture far from Earth and develop the capabilities to do so (eg. radiation shielding, closed loop life support, etc). It’s therefore not a “stunt” to visit a NEO. It’s an important step along the way. It is also important for other reasons. We need to learn more about the different types of objects that could threaten the Earth and figure out ways to deflect them. It also has great scientific value.
I’m also all for developing cislunar space. Fuel depots and visits to Lagrange points will help for that.
We don’t have the money to do everything at once. Flexible Path seems like a prudent way to go. If we lay out a series of developmental steps towards an ultimate goal, there is a chance that it could last across multiple administrations. If it doesn’t, then we may at least have fuel depots, which is game changing for many applications.
Stefan
Please keep the discussion polite people. Being polite doesn’t mean that you have to agree with everything everybody says. It is perfectly reasonable to say that you see things differently. Calling people names doesn’t help the quality of the discussion at all.
Flexible Path looks great on paper.
Then again General George McClellan’s Army of the Potomac looked great on the parade ground.
Actually doing stuff also matters.
Paul, I tend to agree with your assessment of NASA. If you believe “NASA is not capable of conducting multidecade R&D projects,” then they surely cannot do a Moon or Mars mission. Why have NASA at all?
OTOH, shorter goal oriented missions NASA can do. They might be more demonstrations than grand “Mission to X, Y or Z.” But they would have goals and dates and budgets with real flight objectives. Like a series of X-plane projects. Not as sexy as a trip to Mars, but more achievable and develop serious new capabilities. LEO Fuel Depot, Moon Orbit Fuel Depot, Lunar Comm/Location system, and stuff like these. All useful and needed.
There is much to be done in cislunar space and much of it is not directly relevant to going to or landing on Mars.
Agreed, but that doesn’t necessarily argue against the principle of a Flexible Path. For the record, I happen to disagree that 1) even minor improvements to boosters are necessary (as opposed to merely useful) for even very robust Mars missions and 2) that the proposed modifications of existing boosters are in fact minor. But be that as it may, existing boosters are certainly good enough for cis-lunar, translunar and lunar operations. This argues for a sequence of:
1) (commercial) spacecraft
2) landers and their orbital precursors, probably concurrently with 1) and probably done in-house for political reasons
3) lunar surface infrastructure and missions
4) game changing technology (cryogenic depots, breakthrough in-space propulsion, aerobraking etc)
5) Phobos/Deimos/Ceres
6) Mars
7) perhaps, one day far in the future, new boosters, but only if *the market* decides it is necessary
If it does turn out new boosters are necessary for Mars (highly unlikely IMO) steps 6 and 7 would have to be reversed. Similarly, Phobos/Deimos missions could be done before lunar surface missions if surface infrastructure was considered too expensive to do soon.
Lunar missions are certainly possible without new technology or new boosters, probably even Phobos/Deimos/Ceres missions. Lunar missions should not have to wait for new technology development or new boosters. Commercial development of space should not have to wait for new technology or new boosters either. The Flexible Path should go to the moon before going to Mars and before achieving technological breakthroughs.
Actually, I have one more thought about all this. Paul would love us to go back to the moon and develop all of the resources there. So would I, but we don’t have the money to do it.
It seems like it could be a great opportunity for international colaboration. What if we develop the crew capsule that launches from an EELV or Falcon 9. We also develop fuel depots so that we could get to the moon without a HLV. What if ESA and/or Russia develop the moon lander? What if Japan or India or China or whoever develops some of the lunar technology for ISRU?
As a multinational effort we may actually be able to afford doing all of the pieces necessary to fulfill the goal of getting back to the moon in an affordable way. Unless we don’t feel like playing with other nations and going it all alone…
I’ve rarely seen any mention of having different countries contribute the needed pieces for an ambitious mission instead of doing all by ourselves.
Stefan
Paul,
Of course reasonable people can disagree on means and ends; but I more often than not see the debate argued between straw-man positions and distortions of the alternatives. I never said you have to like flexible path or that it is the only possible option — but I can tell from the arguments that many people do *not* address what it is or is not. Serious consideration of the policy options requires consideration of what the policy options actually *are*.
“But NASA can’t do it” is an argument from authority and hence not arguable. You believe it is true and I can’t change your mind. You may even be right. Of course, examination of the last 40 years would suggest the same argument applies to *any* *other* possible forward course of government human spaceflight effort. Everything NASA has tried to resume human exploration since its cancellation (which pre-dates the end of the Apollo program), has failed. That includes the original VSE, of course. I happen to believe that that was because of poor execution not because it was a bad idea — but I don’t know how to guarantee that will change.
There are two possible responses to that situation. One is to give up and scrap the enterprise; one is to keep trying while learning the lessons from what came before. I think it is worth another try, myself.
I like to think that the clearly stated, long-term goal should be *settlement* of the solar system. With that in mind there are many valid reasons to visit asteroids, not just scientific curiosity. Flexible path looks like the most reasonable way to pursue this.
In my mind the central feature of Flexible Path is reducing the cost of doing things in space. Shuttle-derived heavy lift looks nice, but I just can’t see any way for it to become cheap enough for anything but a crash, Mars-or-Bust space program. Since there seems to be no urgent need for a crash program and the Constellation Program has fairly well shown that such programs take longer and cost more, let’s try doing something different this time.
Paul, as usual, cuts through the fog and gets to the truth of the matter. Not only NASA cannot do a multi-decade R&D program without a direction, but no one can.
Rand can sneer all he wants, in his usual caustic way, but “look but don’t touch” (actually under Obama, “don’t look, don’t touch, and don’t even go) is a road to nowhere. The Moon is the gateway to the Solar System. Any other path is not sustainable.
The Russians had plans to use Proton and Soyuz to launch a lunar orbiting mission. Without LOX/LH2 even. The launchers we have today are perfectly capable of doing this sort of mission.
Add a fuel depot and you could start doing a regular moon ferry. If you have more money you can develop ion drives, solar-thermal propulsion, tethers, or whatever and need way, way less mass to be transported. However no engine development is required for the plan to work.
I also think a three man crew complement is not necessary anymore because of automation. Two is enough. Unlike the monster missions NASA planned just so they could justify building Ares V (what was it 4 people?). Add a lunar ascent module to the architecture.
Fund a set of prizes to figure out how to explore lunar, or other easy to reach, in space resources.
At the same time probes could be sent to map NEOs. The problem with NEOs is the travel takes a long time, so a robotic craft is perfect until we develop the necessary technology for long distance travel.
We are talking about a long term plan using a stepping stone approach. This is why flexible path makes sense.
However for this to happen there needs to be a long term vision.
You also need to consider R&D will *always* be required. If you consider you can do massive R&D spending and then just use the system, that won’t work. Initial R&D can take years, or a decade, but after a couple of decades a system will be obsolete. You need to start developing a new system soon after the current one is in place. This is one reason why the Shuttle failed as part of a long term space exploration perspective.
The ISS failed in the sense it was nothing like the space stations serviced by a Shuttle in the von Braun plan. Instead of it being an orbital factory, depot, and in space waypoint to the Moon, it turned into a dead end. Well at least we still got some pretty pictures.
Mark said “The Moon is the gateway to the Solar System”. I would disagree, and say that LEO is the gateway to the everywhere. Unless we can create a way to enable lots of people and cargo to go to LEO on a constant basis, then we will not be able to support anything but one-timer expeditions.
Paul says…
NASA is not capable of conducting multidecade R&D projects. Period.
They seem to be incapable of doing multi-year projects correctly.
Period.
see: ARES I, the next Mars rover, etc.
I think the problem is not being able to do R&D projects that are multi-administration. It’s the same old problem of administration B not wanting (and really not being able) to expend the effort to bring administration A’s grand and glorious scheme to conquer the cosmos to reality. This has been going on since NASA began. The only reason Apollo went the way it did is because you had an administration that (for a variety of reasons) had a vested interest for continuing it. Once the deed was done though, the next administration had no problem killing it slowly.
The answer is to make the process as easy as possible for future administrations to continue the program. Flexible Path seems to do that. Each administration can add (or not) to what is going on and claim ownership (or not). In either case, you are not trying to lock one administration into another’s program.
Paul says…
NASA is not capable of conducting multidecade R&D projects. Period.
The NACA conducted a multidecade (1915-1958) R&D program that was crucial to the survival and growth of the US aerospace industry and that, incidentally, helped win WW II. If NASA really is incapable of of doing such a thing, get rid of it and create a new agency that can.
I meant –
The NACA conducted a multidecade (1915-1958) R&D program that was crucial to the survival and growth of the US aerospace industry and that, incidentally, helped win WW II. If NASA really is incapable of of doing such a thing, get rid of it and create a new agency that can.
Good point, Chris L. I still snicker at the idea that space is the only place where the Obama Administration thinks the answer is “less government”
Couple of points:
1. We won’t get into space until someone figures out how to make a buck up there. Even government sponsored “settlement” is a non-starter. Capitalism will be the prime mover.
2. Space is the place. Think in terms of “high ground” and delta-v. Since solar energy is free and resources are ubiquitous, the “value” of any resources on the wrong end of a gravity well is minimal.
I always thought that Bush’s Luna then Mars was a fine approach, never expecting NASA (just one more government bureaucracy) to get more than halfway. So, “flexible path” sounds as good as anything else; at least it seems to be a start on building the infrastructure.
Kirk, the reason “we want to go to Mars” is, as Greason has previously explained several times in several places, he and the rest of the committee members agreed that permanent human presence on and colonizing Mars is the future of humanity. That there really is no point to be doing any of it unless we believe strongly that we will be living there (off Earth) in our lifetimes.
I agree with the collective amusement with the idea that democrats only believe in capitalism outside the atmosphere… that said, at least there’s one place Obama doesn’t want to socialize. He is apparently pointing the sign toward where he’d like those of us who still believe in freedom to go…
I’m glad that Greason and the other committee members consider Mars to be the future of humanity. Care to explain why? I can’t fathom why the future of humanity is on a dry frozen rock that makes Antarctica look like a tropical paradise in comparison.
Mars is heaven compared to the Moon. As for the future of humanity we need to become a multiple planet species or risk becoming irrelevant. Or extinct. If we can survive living on Mars we can also survive as a species with a significantly higher probability if the Earth becomes more inhospitable for some reason. As happened several times in the past for not totally well understood reasons.
Yawn, you’re all off topic. This post is about Jeff’s frustration with people misrepresenting the Flexible Path. As such, only Paul is on topic, by doing such misrepresentation, and those replying to him *about the misrepresentation*.
And to me, it sounds like how old married couples argue.
Wife: you don’t need to take the car to go to the store, it’s only down the street.
Husband: well if we’re never going to use the car again, why don’t I sell it?!
Jeff,
Of course, examination of the last 40 years would suggest the same argument applies to *any* *other* possible forward course of government human spaceflight effort. Everything NASA has tried to resume human exploration since its cancellation (which pre-dates the end of the Apollo program), has failed.
You miss my point about government spaceflight. It is not that it cannot be done — it is that when there is no specific mission stated or destination targeted, the agency tends to go in circles and feed upon itself. Yes, we have not been back to the Moon, but after Apollo, the goal was to build a reusable spacecraft and a space station, both of which were done. Each project had some specific goal in mind and a timeline to achieve it. I am not arguing that those are models for future success in space, but there was accomplishment, such as it is.
In contrast, the agency’s declaration that they intend to “invest in technology” is a prescription for endless viewgraph engineering, committee meetings, management retreats and paper studies. I speak on this not “from authority” as you have it but from direct observation of 30 years of working for and with the agency.
I do not question the purity of your motives nor the intrinsic logic of a “flexible path” in theory. In a sane world with a competent agency, such would indeed be a good way to proceed, carefully developing the technical base that you need and then going on a well defined mission to some destination when you’re ready.
Alas, such is not the world we live in nor the entity we’ve inherited. NASA needs direction lest it flounder helplessly. The VSE was a well considered, well specified direction. I do not defend the agency’s implementation of it. But the suggested FP alternative that you guys came up with is not the answer. It is destined to be implemented in the classic agency fashion: consensus management (i.e., no leadership), development of numerous options (i.e., indecision), and re-booting of effort (i.e., failure to come to closure).
I agree with you that it’s worth another try. If I did not think so, I would waste no more time upon it. What is needed is not to scrap the VSE, but only the agency’s unaffordable implementation of it. It should be re-born in its original, pre-ESAS incarnation. Despite your protest to the contrary, I think the Augustine report gives the original mission short shrift — it caricatured the VSE objective as a “human Mars mission.” I think that is too narrow and unsupportable a focus. The original meaning was to develop sustained, permanent human presence off-planet through the use of lunar and other space resources. I still think that is a good mission statement and a path towards that could be developed within the existing budgetary envelope.
You also need to consider R&D will *always* be required. If you consider you can do massive R&D spending and then just use the system, that won’t work. Initial R&D can take years, or a decade, but after a couple of decades a system will be obsolete. You need to start developing a new system soon after the current one is in place. This is one reason why the Shuttle failed as part of a long term space exploration perspective.
This illustrates one of the reasons why US space systems are so expensive – the never ending “hobby-shopping” of R&D. Engineers get paid to tinker with things, to make them better. In this area, the Russians do space better. They design and perfect a system and then build the hell out of it with improvements being introduced only when they make sense, not when someone artifically calls a working system “obsolete.”
Consider the R-7 rocket family. It’s genesis dates back to the world’s first ICBM and the rocket that launched Sputnik. It was upgraded and used to launch Gagarin and the other early manned flights. In the mid-1960s, it was upgraded again to create the Soyuz booster (SL-4 in US designation), and they added an additional upper stage to create the SL-6 Molniya. Once they worked the bugs out, they built and flew them by the hundreds. The reliability is about 97% (on par with US systems), the cost per ton to orbit is relatively low, and it’s even man-rated. In all, they’ve launched over 1500 SL-4s and SL-6s with only incremental upgrades. I’m sure American engineers will point at the Soyuz and call it obsolete but the fact is, it’s flying, it’s affordable, and it works. The Soyuz is very close to the “Big Dumb Rocket” proposal in action and I mean that in a good way.
We need some basic technology before we can go further in space. For example, we need a closed loop life support system that’s good for at least a couple years if we’re going to Mars. Fine, design, test and build the technology for such a system and then leave it the hell alone. Don’t fall for the “if we only spent a few billion dollars more, we could save a few kilograms in mass and last a few weeks longer in space” trap. Quit the hobby-shopping and get things done. Some systems like electronics do become obsolete quickly. Build modular systems that allow for incremental upgrades. Get the job done and quit dicking around.
Larry, I think the root problem is that there’s too little cost pressure on American rocket designers. The Soviets/Russians had to be efficient because they never had lots of funding. So they took a conservative approach and just tweaked the same basic design for 50 years. But there was never a functioning market with competition. That’s what we really need — both to drive innovation and to drive down costs.
Paul, I’m afraid it’s more than a specific destination, it is a true national NEED to go to that destination that is required to keep NASA from simply “feeding on itself”. In the 1960s, the US had to land a man on the Moon to beat the Russians and show national superiority. NASA was the vehicle organized to execute that mission, but the mission had to be done, one way or another. National credibility was at stake, and the hearts and minds of the world. It was war by another means.
There is no such need today, and NASA leadership knows it. Thus, when any project is announced they use it as an excuse to build their empires rather than accomplish the mission. Griffin’s behavior during the Constellation program was Exhibit A of this.
The only true “national needs” in space right now are being met by the NRO, the Air Force, ULA, and the commercial geosynchronous satellite community. They are executing on a daily basis activities in space that meet key national needs. Unfortunately for NASA, it is no longer a part of any national-need-type activities in space, and has not been for some time. There is little reason to think NASA will ever be tasked to meet real national needs in space anytime in the future. NASA’s fixation on ruinously-expensive human spaceflight probably has a lot to do with this.
NASA is not organizationally capable of executing a multi-decade technology research program ending with the building and use of real flight hardware in the absence of a specific goal, destination or time table.
This sentence started out well, but the last half of the sentence is moot. NASA is incapable of executing an HSF-scale project within anywhere close to the original budget and schedule even when given a destination and timetable. Saying that a destination and timetable will fix the Exploration Directorate is like saying that replacing the spark plugs will fix a totaled car.
So Kirk, it really does sound like one could distill your position to:
In the 1960s, the US had to land a man on the Moon to beat the Russians and show national superiority. National credibility was at stake, and the hearts and minds of the world. There is no national need for human spaceflight now.
Is that a fair characterization?
I think the weak answer given in response to this goes something like this:
The US is a world leader in human spaceflight. This is acknowledged around the world. So national prestige is certainly still an issue, and canceling human spaceflight would be damaging to that. Human spaceflight has an inspirational effect which increases enrollments in science and engineering degrees, and this has national security implications.
Or, to boil it down even more: human spaceflight is an advertising program for the science and engineering strength of our national defense.
I, for one, think this is a terrible justification for a human spaceflight program and would prefer to say things about off-world resources but that wouldn’t be a discussion about what is, it would be a discussion about what I think should be.
OK, Karl, then the corollary becomes: explain why a human Mars mission might be only expected to cost a few billion dollars instead of hundreds of billions of dollars
Because there’s nothing about such a mission that requires it to cost billions, much less hundreds of billions. My simple two step plan here.
1) NASA demonstrates that it can do extended BEO missions (to Lagrange points, Moon, NEOs, whatever) within the budget constraints, by actually doing a few within budget constraints.
2) Do the mission.
If one of these steps fails, then the mission doesn’t happen or doesn’t complete. I don’t have a problem with that. And my highly detailed plan is just as good as most in this thread.
Frankly, I don’t see a compelling national need to go anywhere unless NASA mission costs drop by an order of magnitude or more. High cost shows a fundamentally unserious approach to space exploration.
Soyuz is similar to the path that Armadillo and Masten and Unreasonable (and Toyota) seem to all have taken: incremental improvement. The short term advantage is that you get something up and running as soon as possible and are able to shorten the development cycle dramatically. The long-term advantage is that you can take advantage of new technologies developed by other people as they become available.
Paul’s beef with Flexible Path is that the goal is too general for NASA’s current culture – that without a much more specific goal, they’ll run around in all directions generating nothing but PowerPoint debris.
The problem is not so much the Flexible Path, but NASA’s organizational culture itself. They need to be reminded that they were once NACA. Break it down into subgoals then – maybe not 181 subgoals but perhaps a few for each of NASA’s centers. Maybe have the various centers competing against each other; make completion of one subgoal mean that they get another, with commensurate funding.
Karl, what’s cost got to do with need?
I need air, no matter how much it costs.
Ed, Paul’s beef with Flexible Path is that he sees it is competition to his vision and there can be only one.
Karl, what’s cost got to do with need?
I need air, no matter how much it costs.
Cost has to do with whether or not you can satisfy that need. It doesn’t matter how much you need that air, if you can’t get it.
The only true “national needs” in space right now are being met by the NRO, the Air Force, ULA, and the commercial geosynchronous satellite community. They are executing on a daily basis activities in space that meet key national needs.
Well said, Kirk. “Exploration” Directorate, if it is to survive at all, should get focused, NACA-style, on technology research (not systems development or “infrastructure”) to make the next generations of these systems more functional and affordable, rather than the navel-gazing astronauts-for-the-sake-of-astronauts, Moon-for-the-sake-of-Mars nonsense that comes out of the pages of early 1950s Collier’s magazines and pulp fiction. A central-planning-of-the-future cult that is alas still generously represented in the comments above. The Soviets couldn’t even make workable five-year plans based on existing industries, and these guys already have the next five decades of futuristic space “infrastructure” planned out for us, and have since the early 1950s. 🙂
Meanwhile, we have the real commerce and real defense that Kirk cited that bear no resemblance to the “next logical steps” of the planning cult. A not-too-distant future generation of these systems may include propellants for boosting and stationkeeping from lunar ISRU. If we run parametric estimates based on serving the real applications Kirk observed, we get a scaling two to three orders of magnitude smaller than the scale of a manned lunar base. In other words, ISRU won’t be done economically until it can be fully automated with machines about the same size as the larger Google Lunar X Prize contestants. So let’s cut out ISRU as a justification for HSF, it’s utter nonsense.
The other way around — that ISRU will eventually make HSF affordable — is far more credible. But the biggest justification for ISRU is making the real space development which Kirk described more functional and affordable, not the old for-the-sake-of-astronauts nonsense.
And will somebody please come up with a better word for it than “ISRU”? The future will thank you.
googaw, acronyms reduce giggle factor, otherwise we could just call it space mining.
Karl, which is entirely my point. Kirk asked what the national need is, your answer is about cost, that can’t be an answer to Kirk’s question.
Dr. Spudis,
Don’t know if you will see this or not, but I am going to throw it out as a crazy idea, and see what people think. You said,
In particular, you seem to imply that it doesn’t have to be an issue of destination. Rather, you also suggested specific mission. So lets give it a specific mission forces itself to move in the sane direction.
Lets give NASA 20 years to focus, not on a particular rocket, or to go to a particular destination, but to solve the killer application problem.
That is, NASA has 20 years to figure out how to build a thriving spacefaring industrial sector, that isn’t solely dependent on NASA for funding. (there might be a more precise way of phrasing this, so anyone who wants to suggest one, feel free)
blah blah blah. the nerds dont even agree why people should be in space. how can they discuss this stuff. they’re throwing darts at different boards.
National needs.
The national need regarding space is energy from space.
[A problem is someone might think I mean that NASA/or someone needs to start by building a bunch of huge SPS or something.
]
There is a national need is to develop a electrical power market in space for space.
It would be in US interest if in the future we could get 1/2 or more of the total global electrical supply from space.
It would in our national interest if the electrical power from space would have a lower overall cost then compared to today’s cost- a cheaper unit cost for consumers.
Abundant future supplies of energy is a top priority in regards to US national security.
“The national need regarding space is energy from space.”
no, that’s what you’d like to be the national need.
But so far that has not been identified as a national need.
Totally agree with Jeff
Another advantage, often unstated or under rated, of the Flexible Path is that it breaks the path to Mars or anywhere else into manageable chunks.
The problem with Apollo and Constellation was that it tried to do everything in a single leap. That’s 15Kps from the earth to the moon and another 15 back (in terms of delta-v).
Flexible path with fuel depots breaks the mission up as follows.
9-10 Kps from ground to LEO .
about 4 to Lunar orbit.
about 4 to the lunar surface and back to Lunar orbit. (2 up, 2 down)
Of course there were good reasons for wanting to do the missions Apollo style. It’s was all about minimising risk.
But fuel depots change everything. Each step is smaller.
Each step can be considered seperately, adding margin, reducing requirements, allowing reusability at each step, and thus reducing costs.
The risk counter is reset at each stage because you can choose to abort at that point without penalty. Also more margin. lower requirements for each segment, and reusability gives you lower risk in the first place.
The hope is that if the Flexible Path is implimented well by NASA we will go further and faster than any of us currently believe possible, and at a reasonable cost. It remains to be seen if NASA can actually fulfull this promise, or if they can manage to stuff it up.
@Paul Spudis:
It should be re-born in its original, pre-ESAS incarnation.
You mean with Steidle’s spirals? Isn’t that precisely a flexible path? From what I’ve seen of it it looks better than the current flexible path. And what do you make of the Huntress et al plan for the ‘Next Steps in Exploring Deep Space’?