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Anyone looked at this idea?
http://www.redcolony.com/marsforless/in … index.html
It's basically Mars Direct but uses rockets available now to deliver everything to LEO in stages with assembly in orbit. I'm sure there are problems with assembling all of this in orbit but maybe they are easier to overcome than the current problem of developing a heavy lift launcher.
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Wieeeeeerd...
I found that scenario just the day before yesterday, and now i see it here!
I think RobS an the author should stick their heads together, and see what comes out of it, th both came up with the same, initial idea: use current launchers, able to put 20-24 tons in orbit.
The author has a good point in that in orbit-coupling = NOT in-orbit assembly, per se. And in recent years 'we' got quite good in the first category.
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I see several interesting parallels with my http://www.users.on.net/davidellard/Pro … pdf]Proton Mars article. It’s validating to see that I’m not the only one who thinks that we can’t do Mars without heavy lift.
"No Bucks, No Buck Rogers" - Tom Wolfe
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That's three like-minded people! Wait 'till GCNRevenger sees this!
(just friendly ribbin' GNCRevenger, eventually we'll need heavy-launch, but it looks like no-one wants to take the risk and build one, markets being what they are...)
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Initially I frowned on this plan because it used on-orbit assembly, but upon rereading it I think I am now a convert. When I first heard about Mars Direct -- about five years ago -- the shuttle was still considered reliable and energia was still revivable. Now it seems that we will have to design a brand new heavy lift launch vehicle. This new plan seems like the best way to get to Mars at the present. Once a Mars base is established there will be a real need for heavy lifters, but right now let's use the medium boosters.
Reading that paper made a Mars mission feel so close I could almost taste it. We,ve already got the Centaur and the medium lift boosters -- Adrian, get us a good frustrated smiley!! Maybe the Mars Society should just start designing the ERV/MTSV common habitat. It's sooooo close....
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Okay so how do we assemble all of this in orbit? Remotely? Has anything like that ever been done before?
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The basic principal of Mars For Less, and my Proton Mars is to dock each unit one after each other in a ‘Train’ configuration. This doesn’t seem any more difficult then a progress re-supply ship. These have been docking successfully for years with Mir, and the ISS.
"No Bucks, No Buck Rogers" - Tom Wolfe
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That's three like-minded people! Wait 'till GCNRevenger sees this!
He doesn't seem to be here right now, so I guess it is my turn to be the skeptic.
In this plan, the size of the habitat and ERV are just too small. Mars Direct is about as small as a Mars mission can realistically be, but it is still larger than this mission. The volume of hab is less than 60% of the volume of the Mars Direct hab, and the habitable volume of the ERV is even smaller.
Also, the cost estimates of designing and building the spacecraft are wildly optimistic. If the hab and ERV are at all comparable to ISS modules in terms of complexity, then the costs should be an order of magnitude greater than the plan envisions.
The idea that a series of centaur rockets is the best way to propel a spacecraft seems very suspicious to me. First of all, it means sending 8 heavy, expensive, rocket engines into orbit when one or two could do the job. In addition, you increase the risk of the mission by requiring that 4 sets of engines work perfectly instead of just one set. Using small pieces also increases the total fuel tank weight, and requires an additional truss to be built. Not to mention fuel boiloff from waiting in orbit during assembly. Finally, considering that it does not really matter how long the travel time is, and that you need a large power source for ISPP anyway, it really makes more sense to use electric propulsion for the ERV rather than chemical.
HLLVs cost less per pound to get payload to orbit. For applications like this, they also get greater value per pound by eliminating redundant parts and structures. These two factors combined mean that Mars missions that use HLLVs will have lower reoccurring costs than equivalent missions that use medium lift launchers. Not just Mars missions either- space stations, moon missions, and almost any other manned space activity can be made cheaper using heavy lift. If we want to get much done in space we will need HLLVs eventually, so why not develop them now?
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Hasn't this docking been done with humans guiding the ship? Are you saying that each stage that is launched to LEO will have pilots that perform this docking maneuver? How are the pilots going to get home?
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Hasn't this docking been done with humans guiding the ship?
Yes. Though Europe's new ATV will have a basic autonomous docking capability.
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It is true that a HLLV would be cheaper per pound, but it would also cost $10 billion or more to develop. Divided among, say, 30 vehicles in the design lifetime, that adds $333 million to each launch! If the vehicles launch 120 tonnes each, it adds about $3000 per kilogram; that's not small change. And that's assuming the HLLV launches 30 x 120 = 3,600 tonnes to low Earth orbit, which assumes a demand for mass to LEO far higher than anything we have today, at a still-hefty price.
That's why the best combination, I think, is medium lift rockets to LEO (like the Delta IV heavy) and solar-ion to the lagrange point. The Mars for Less plan would need half as many launches with that technology.
-- RobS
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Hasn't this docking been done with humans guiding the ship? Are you saying that each stage that is launched to LEO will have pilots that perform this docking maneuver?
The first ISS modules (US<>Russian, to boot,) coupling was 100% automatic (well, with some help from Mission control, of course)
There was *NO* human presence in orbit. So it is possible.
Euler, good points, esp. cost that seems wildly optimistic.
I still like RobS' Mars24 best, though: scalable, a lot of redundancy, flexible, scope for private enterprize to fill in the niches... (like ion propelled tugs, see Orbital Recovery, for instance...)
HLLV is essential in the long run, but reading the launch market predictions, it would be economic suicide to build one today, regrettably. Looks like medium-sat to LEO(!) is the only place where market expansion is going in the near future, sigh...
So make-do/ can-do with the launchers we have, while keeping an eye on the HLLV as an ultimate workhorse for serious expansion...
(ok, rambling... )
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Hasn't this docking been done with humans guiding the ship? Are you saying that each stage that is launched to LEO will have pilots that perform this docking maneuver? How are the pilots going to get home?
The Sowiets coupled part of space-stations in 1983 or 1984 (Salyut 7 and Cosmos 1443) without cosmonauts above. That can't be the problem
What's better, using much small rockets and coupling or one big with high development costs? I think something between is the best match.
To prevent boil-off in Earth Orbit it's possible to design eg 3 stages and your habitat. The habitat first is in circular LEO. The 1 stage is launched, docks and accelerates to slight elliptical orbit. Then this stage is jettisoned (and can eventually be reused). The second stage is launched in circular LEO and makes a first burn to RV with the habitat. It docks, burns and put the habitat in a high elliptical orbit. Also this stage is jettisoned and eventually recovered. The last stage is launched in LEO, burns to RV and dock with the habitat and gives the final injection-burn.
Problem, of course, is that the last stage has to make at least one orbit of at least a week.
An advantage is that the Mars-train will not get very long.
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Thanks for the save Euler, busy week...
This plan is way, way too small... the whole MarsDirect hab is only like three and a half times as wide as your bed is long with two low-ceiling levels that also has to be your entire Martian laboratory and airlock facility and food storage and part of the LSS and so on... MarsDirect is even foolishly optimistic in its small size, particularly the ERV which is even smaller still, if anything a Mars mission must be bigger and not smaller. An HLLV in the 150MT to 200MT region ought to be a starting point for any single-shot chemical mission.
Multiple small launches of regular TMI stages also isn't all that practical because of fuel boiloff, requiring some condenser mechanism which would be quite power hungry and complex, which you wouldn't need if all your fuel was brought up in the space of 1-2, maybe 3 shots. Sending up cryogenic fuel by ion tug in any configuration is also a non-starter without a condenser. And as Euler mentioned, thats alot of engines to have to rely on... you can't send them up and fire them off right away to make a more eliptical orbit easily because each subsequent stage would have to match orbit - requiring fuel of its own - and how do you intend to put people into such an orbit to rendevous?
I like the idea of sending up the entire vehicle in a few shots of a 100-120MT class HLLV; one for the vehicle proper and lander/acender (perhaps some fuel), one for the NERVA-NTR TMI stage and partial fuel, and one for a fuel tank... either the drive or hab section would carry a nuclear fuel condenser and the hab section would have an aerobrake shield. The whole thing would be reuseable, with future crews launched by EELV and the vehicle fueled by HLLV tankers.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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This Zubrin e-mail arrived today in my AOL in-box.
NASA-ESA Study Shows Mars Direct Affordable May 26, 2004
For further information about the Mars Society, visit our website at http://www.marssociety.org]www.marssociety.org
A joint study conducted by NASA and the European Space agency (ESA) shows that a humans to Mars program based on the Mars Direct mission plan is affordable.
The results of the study are reported in a paper written by Charles Hunt of the NASA Marshall Space Flight Center (MSFC), Huntsville, Alabama and Michel O. van Pelt of the ESA European Space Research Engineering Centre in Noordwijk, the Netherlands. According to the Hunt/van Pelt paper, NASA costing models show that the Mars Direct plan could be implemented for a cost of $39.4 billion for all hardware development plus the first mission, with each follow-on mission costing an additional $7 billion, while ESA costing models show Mars Direct costs for development plus first mission as $26.6 billion, with each follow on mission costing $5.2 billion. While cost estimates for mission designs can never be precise, it is clear from the Hunt/van Pelt led NASA-ESA study that the real cost of a well-planned humans to Mars program can be kept to the range of several tens of billions of dollars, not the many hundreds of billions spuriously claimed by opponents of human Mars exploration.
A complete session devoted to discussing plans for achieving human Mars exploration will be held at the 7th International Mars Society Convention, Palmer House Hilton, Chicago, August 19-22. To present a paper, submit an abstract of no more than 300 words to msabstracts@aol.com by May 31, 2004.
It appears to fit into this developing thread.
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I wonder if that ESA estimate is using Nasa SDV launchers or RSA Energia? It sounds a little low to me
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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It is true that a HLLV would be cheaper per pound, but it would also cost $10 billion or more to develop. Divided among, say, 30 vehicles in the design lifetime, that adds $333 million to each launch! If the vehicles launch 120 tonnes each, it adds about $3000 per kilogram; that's not small change. And that's assuming the HLLV launches 30 x 120 = 3,600 tonnes to low Earth orbit, which assumes a demand for mass to LEO far higher than anything we have today, at a still-hefty price.
That's why the best combination, I think, is medium lift rockets to LEO (like the Delta IV heavy) and solar-ion to the lagrange point. The Mars for Less plan would need half as many launches with that technology.
-- RobS
Form follows function. Why influences how.
What is the goal of going to Mars? Tell me that and I can better choose between EELV and HLLV.
If its just to collect rocks without immediate intentions of staying more permanently, then RobS may well have a point. 30 missions for a $10 billion HLLV is not economical.
But if the goal is to begin a more permanent presence we simply cannot build enough Delta IV barrels and the much higher cost per pound will eat us alive.
Besides, the Russian use this same achitecture with Zenit and Proton and crush us on the economics of it all. If we are going the EELV route, a joint mission with Russian boosters is the only way to make it affordable.
= = =
Frankly, if the projected NASA budget will do nothing more than put some geologists on the Moon and Mars with NO permanent infrastructure or permanent presence AND we will pay many times the costs per pound for Delta versus Zenit or Proton, I might well join the robots only camp.
If we want permanent presence "out there" be it the Moon or Mars we need HLLV =OR= we need an international program.
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If we want permanent presence "out there" be it the Moon or Mars we need HLLV =OR= we need an international program.
Or both.
It won't get started without an international program and it won't last without HLLV.
Maybe the way to sell it is to say Proton is doing the job 'till the HLLV is ready?
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I wonder if that ESA estimate is using Nasa SDV launchers or RSA Energia? It sounds a little low to me.
Or the NASA quote is high. NASA is not famous for doing thing cheaply.
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It is true that a HLLV would be cheaper per pound, but it would also cost $10 billion or more to develop. Divided among, say, 30 vehicles in the design lifetime, that adds $333 million to each launch! If the vehicles launch 120 tonnes each, it adds about $3000 per kilogram; that's not small change. And that's assuming the HLLV launches 30 x 120 = 3,600 tonnes to low Earth orbit, which assumes a demand for mass to LEO far higher than anything we have today, at a still-hefty price
I'm confused by this. how can an HLLV be both cheap and dear, which is what seems to be being said here?
I've said before that ironically, the cheapest way to have a HLLV (or semi-BDB) quickly is to resurect Saturn V.*
- It does not have to be designed; it already is. (Contrary to popular rumor, several copies of the design drawings are stashed away at various locations.)
- If all else fails, a visit to Houston or the Cape with a measuring tape could resolve most dimensional problems for the builders.
- It could be built now with cheaper and lighter components than back in the 1960s, without anything more than minor redesign.
- We know it works; all we have to do is get a production line up and running.
If Saturn had still been in prouction since the '60s, the probable cost per lb to LEO would have been about $1200 or better ($2650/Kg) by now, at which price a 120 tonne delivery to LEO would have cost $318M. Even a Proton (today's cheapest option) at $100M per launch for 22 tonnes costs $4500/Kg-- almost twice the price.
And building a new HLLV from scratch? Well, let's accept that $10B development cost for the moment. The extra $3000/Kg for that would push the full cost per Kg/LEO to $5,650-- more than Proton (with its highly dubious Russian economics) but less than any of the rest, and able to deliver seriously big chunks of your Mars ship (or anything else big) without all that nasting component-docking-together while the H2 boils off, and with a serious size for the crew accommodation.
*(When you get right down to it, the apparently-obvious alternative, the Energia, is not so wonderful an option. The much-touted heavy-lift version was never built except as a special semi-heavy to lift Buran, and the true HL version was just a design concept. As for what it would cost or how long to get ready, don't ask the Russians. They won't tell you, probably because they don't know any better than you or I do.)
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Nah, the cheap-cheap way would be to do a Shuttle-Derived setup... 5-segment boosters, RS-68 first stage, RL-10 or RS-60 second stage, EELV derived hardware as much as possible... it may cost a little more per flight, but everything is available in production right now with a minimum of development. The bigger boosters, the cryogenic engines, and the launch infrastructure are all tested and available in short order.
As for resurecting the Saturn rockets, that ain't gonna happen... The big F-1/F-1A engines, the J-2 cryogenics, and the like to make them go... all gone. Nobody makes them anymore, and it would take considerable time, effort, and money to rebuild them even with blueprints. The original Saturn wasn't all that cheap either, costing around $2Bn a pop not counting development dollars.
I agree that the Energia HLLV is just a Russian vaporware bragging right... I don't think they could build one right now even if they had the money, with the poor state of the original manufacture and launch facilities (which have been converted to other productions), there are few RD-0120 engines left, and the factory to make them retooled.
The best solution in the long run is probably a clean-sheet vehicle, most likly taken from the post-Saturn NOVA concepts but using current hardware (RD-170/180, RS-68, Aerojet SRBs etc) as much as practical to make a vehicle that can do roughly a little more than Saturn with a target price of under $1Bn a pop.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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http://www.thespacereview.com/article/150/1]This guy agrees with GCNRevenger.
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I think that combining medium lift technology and heavy lift technology as GCNRevenger suggested is a fantastic idea.
Dig into the [url=http://child-civilization.blogspot.com/2006/12/political-grab-bag.html]political grab bag[/url] at [url=http://child-civilization.blogspot.com/]Child Civilization[/url]
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Nah, the cheap-cheap way would be to do a Shuttle-Derived setup... 5-segment boosters, RS-68 first stage, RL-10 or RS-60 second stage, EELV derived hardware as much as possible...
No, please no!
ANYTHING to do with Shuttle is thrice cursed.
When you consider NASA's estimate for the Shuttle-C mods over 10 years ago was over $5bn....
Please, on NO account touch anything to do with Shuttle!
it may cost a little more per flight,
The whole point is to do it cheap.
As for resurecting the Saturn rockets, that ain't gonna happen... The big F-1/F-1A engines, the J-2 cryogenics, and the like to make them go... all gone. Nobody makes them anymore, and it would take considerable time, effort, and money to rebuild them even with blueprints.
I think you are wrong. In fact I know you are. I am sure it could be built again without all that much difficulty.
The original Saturn wasn't all that cheap either, costing around $2Bn a pop not counting development dollars.
It was $2bn including development. If you separate ot away from development, it cost far less per launch than Shuttle, allowing for price inflation, and getting 6 or 7 times more useful payload to LEO than Shuttle.
I think that combining medium lift technology and heavy lift technology as GCNRevenger suggested is a fantastic idea.
I think it sounds like an excellent way to get the worst of both worlds.
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Actually, Astronautix lists the development cost of the Saturn-V and the launch costs separatly. If you account for inflation of about 5x to get you from 1967 to 2000 dollars, development of around $38Bn and a fly-away cost of around $2.2Bn, which is pretty close to the quoted $2.8Bn in 2004 dollars you see floating around the space news.
Easy to revive Saturn ey? Really? Why?
The engines aren't being built anymore by anyone, the original tooling gone, the original engineers mostly gone, the subcontractors gone too as far as the engine is concerned, the electronics would have to be redone from scratch (vacuum tubes, transistor bulbs?)... we have blueprints and a museum piece or two, and thats all. Making a device or system of such complexity from a blueprint and an old rusty example, easy? I think not... a blueprint doesn't tell you anything about how you make the parts, the nuances of assembling them such that they don't explode with the extreme conditions of the F-1/A, and other unknowns which would have to be redone from square one.
The Shuttle system, sans the orbiter, it not that far removed from the the "son of Saturn" Nova concepts, and is not in itself inherintly dumb like Shuttle. The pieces for such a vehicle are available now, right now today... the bigger SRBs, the RS-68, and/or the RD-170/180. It is worth noting that the Shuttle SRBs produce as much or more thrust than the F-1A would, the RS-68 which you can also buy right now produces nearly tripple the power of the old J-2, and if you want RP1 engines the fine Russian RD-170 which you can buy right now today this minute produces similar thrust as the F-1.
A shuttle-derived vehicle would not be like Shuttle. It would not be like Shuttle. In fact, it would more closely resemble a large EELV than it would Shuttle, probably also using the same guideance systems and the same upper stage engines and some similar construction. If you wanted to build a clean-sheet vehicle with EELV technology, it would probably even wind up resembling an SDV.
Oh and if you may recall... Saturn-V used the same VAB, the same crawler, and the same launch pads as Shuttle does today. Even the STS main tank is built in the same factory as the Saturn-V tankage was.Its simple really, try to learn how to build a too-expensive rocket from the past all over again, or build a new rocket out of things that we already have that are just as good... Oh, and we know how to build rockets around the modern hardware already too. (Delta, Zenit, Atlas, Shuttle, etc)
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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