Both robotics and HSF have their place. The FY11 plan is all about developing the infrastructure to enable regular human missions to places like mars in an affordable way.
If Congress instead chooses to stretch out budgets and drop critical research then I agree with you that talk of exploring Mars by humans is a nice goal but not realistic. Your budget argument only makes sense if we abandon attempts at new strategies (prop depots, cyclers, etc.) and try to go at it Apollo style.
How is the FY11 plan affordable?
I am not just being critical of it, but I genuinely do not see any dramatic 'cost saving' advances to be made in a 5-10 year research program (at least none that are being seriously discussed in open debate).
A new Kerolox engine will perform in the same ballpark and for the same cost as existing hydrolox engines - certainly nothing here to reduce the cost per kg to LEO by even 20%. The total number of engines built would have more impact on the cost to orbit.
Super propulsions like Plasma and Ion are unsuitable for launch, thus of no impact until the 2025+ missions.
NTR are not under development (and for good reason) although these might change ISP enough to really impact costs.
The areas that COULD impact costs and ARE being discussed include EELV based Flexible Architectures and Fuel Depots. As far as I know, neither of these needs any real research.
If EELVs and Fuel Depots are the path forward, then why doesn't the FY11 plan just shift 5 years and start development right now. There are no technology 'game changers' on the horizon.
I don't see anything that will change the Augustine Commission cost estimates, so why burn Billions of dollars with unnecessary delays and usefull - but not game changing - research.
You make a lot of assumptions here.
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k? Scale that up, would be a very cost-affordable HLV engine, yes?
You make a lot of assumptions here.
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k? Scale that up, would be a very cost-affordable HLV engine, yes?
My only real assumption is that comparable (both regen or both ablative, similar total thrust) Hydrolox and Kerolox engines, produced in comparable numbers will have similar costs.
The concept that an 'affordable' program involves building HLV engines in bulk seems less likely. Twenty-five Jupiter 130 launches per year would dramaticly reduce costs using existing technology, but who has 1,750 tons of stuff that needs transport to LEO? Kerolox will not change that.
As I said, forgetting about whether the research will actually be successful, what technology would reduce cost to orbit by even 20% within a 5-10 year period? The FY11 plan seems to expect a breakthrough that will alter one of the important paramters in the basic rocket equation. How else will costs be dramaticly reduced from all of the options available to us today? We have commercial access to space already. Flying people will not halve the cost per kg to orbit from what communication sattelites pay.
...
Of course, with the smallest (10-20m-class) meteoroid-sized NEOs, even a 'docking' is impossible. However, larger Earth-grazers could use a landing platform.
...
Probably a naive question, but I just gotta ask: has it ever been suggested to "capture" a very small asteroid, James Bond style (You Only Live Twice). Before you think I'm mad, I'm not suggesting actually moving the asteroid, but simply surrounding it with an inflatable shell (Bigelow style), i.e. the shell and asteroid are in the same solar orbit. Bigelow's Sundancer will be around 6m in diameter and 8.7m long, so the order of magnitude is the same as a 10 - 20m asteroid.
Then pressurise the shell and allow astronauts to work in a shirt sleeve environment?
I presume the main problem with inflatable craft is that the docking ports are not inflatable and are limited in size to the launch vehicle's diameter?
I'm starting to regret asking this question, so I'm gonna press the "Post" button before I change my mind ...
...
Of course, with the smallest (10-20m-class) meteoroid-sized NEOs, even a 'docking' is impossible. However, larger Earth-grazers could use a landing platform.
...
Probably a naive question, but I just gotta ask: has it ever been suggested to "capture" a very small asteroid, James Bond style (You Only Live Twice). Before you think I'm mad, I'm not suggesting actually moving the asteroid, but simply surrounding it with an inflatable shell (Bigelow style), i.e. the shell and asteroid are in the same solar orbit. Bigelow's Sundancer will be around 6m in diameter and 8.7m long, so the order of magnitude is the same as a 10 - 20m asteroid.
Then pressurise the shell and allow astronauts to work in a shirt sleeve environment?
I presume the main problem with inflatable craft is that the docking ports are not inflatable and are limited in size to the launch vehicle's diameter?
I'm starting to regret asking this question, so I'm gonna press the "Post" button before I change my mind ...
I'd vote to fund it just on the merit of seeing if it could be done.
IIRC, the Apollo crew commented that the moon smelled bad (inside the lander). I would imagine that the asteroid might have similar issues ... but what are a few heavy metal compounds between friends.
... what technology would reduce cost to orbit by even 20% within a 5-10 year period? The FY11 plan seems to expect a breakthrough that will alter one of the important paramters in the basic rocket equation. How else will costs be dramaticly reduced from all of the options available to us today?
Your logic is quite compelling. Look at it a different way, though. Suppose the plan were to mothball the NASA capability to do heavy-lift engine and vehicle design and integration, and then restart that capability in 10 years. Would the cost for that be substantially different than the amount available for heavy-lift "R&D" in the FY11 budget proposal?
You make a lot of assumptions here.
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k? Scale that up, would be a very cost-affordable HLV engine, yes?
My only real assumption is that comparable (both regen or both ablative, similar total thrust) Hydrolox and Kerolox engines, produced in comparable numbers will have similar costs.
The concept that an 'affordable' program involves building HLV engines in bulk seems less likely. Twenty-five Jupiter 130 launches per year would dramaticly reduce costs using existing technology, but who has 1,750 tons of stuff that needs transport to LEO? Kerolox will not change that.
As I said, forgetting about whether the research will actually be successful, what technology would reduce cost to orbit by even 20% within a 5-10 year period? The FY11 plan seems to expect a breakthrough that will alter one of the important paramters in the basic rocket equation. How else will costs be dramaticly reduced from all of the options available to us today? We have commercial access to space already. Flying people will not halve the cost per kg to orbit from what communication sattelites pay.
http://en.wikipedia.org/wiki/Deep_Space_1http://www.adastrarocket.com/aarc/Electric propulsion tugs could be used to efficiently pre-place propellant depots and equipment. Also, by separating cargo and crew, you can use more efficient trajectories for the cargo than you would if it has to go quickly with the crew, even if you're just using chemical rockets.
Also, in the case of propellant depots, you aren't necessarily changing the rocket equation itself, but since many small launches can be used for the propellant, a reusable tanker craft makes sense (both the on-orbit tanker and the launch vehicle can be reusable, especially for LEO depots). Reusable makes sense if the spacecraft's mission is short (the tanker spacecraft just needs to rendezvous with the depot in LEO and return, less than a week I'm sure) and many times a year (small launch vehicles, while more expensive per pound at the same number of launches per year as a larger launch vehicle, can reach above 40 launches per year for the same amount of mass in orbit as four HLV launches a year, which is firmly reusable launch vehicle territory).
Propellant depots combined with high-Isp solar-electric propulsion (slow but efficient) really does change the rocket equation, the same way that petroleum is transported by pipeline or ship or rail instead of jet airplanes, which is less than 10% as efficient per ton-mile of freight.
You make a lot of assumptions here.
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k? Scale that up, would be a very cost-affordable HLV engine, yes?
My only real assumption is that comparable (both regen or both ablative, similar total thrust) Hydrolox and Kerolox engines, produced in comparable numbers will have similar costs.
The concept that an 'affordable' program involves building HLV engines in bulk seems less likely. Twenty-five Jupiter 130 launches per year would dramaticly reduce costs using existing technology, but who has 1,750 tons of stuff that needs transport to LEO? Kerolox will not change that.
As I said, forgetting about whether the research will actually be successful, what technology would reduce cost to orbit by even 20% within a 5-10 year period? The FY11 plan seems to expect a breakthrough that will alter one of the important paramters in the basic rocket equation. How else will costs be dramaticly reduced from all of the options available to us today? We have commercial access to space already. Flying people will not halve the cost per kg to orbit from what communication sattelites pay.
http://en.wikipedia.org/wiki/Deep_Space_1
http://www.adastrarocket.com/aarc/
Electric propulsion tugs could be used to efficiently pre-place propellant depots and equipment. Also, by separating cargo and crew, you can use more efficient trajectories for the cargo than you would if it has to go quickly with the crew, even if you're just using chemical rockets.
Also, in the case of propellant depots, you aren't necessarily changing the rocket equation itself, but since many small launches can be used for the propellant, a reusable tanker craft makes sense (both the on-orbit tanker and the launch vehicle can be reusable, especially for LEO depots). Reusable makes sense if the spacecraft's mission is short (the tanker spacecraft just needs to rendezvous with the depot in LEO and return, less than a week I'm sure) and many times a year (small launch vehicles, while more expensive per pound at the same number of launches per year as a larger launch vehicle, can reach above 40 launches per year for the same amount of mass in orbit as four HLV launches a year, which is firmly reusable launch vehicle territory).
Propellant depots combined with high-Isp solar-electric propulsion (slow but efficient) really does change the rocket equation, the same way that petroleum is transported by pipeline or ship or rail instead of jet airplanes, which is less than 10% as efficient per ton-mile of freight.
Are any major breakthroughs needed for SEP or Depots?
I was under the impression that the answer is no.
So why wait 5 years to begin the design?
If THAT is the POTUS's plan, then he should just say so and start designing TODAY.
I prefer Direct over Flexible EELV, but either plan seems workable without a decade worth of research. How will the RESEARCH lower the costs more than a small margin?
Please see Robot beats post above. We don't have fuel depot technology, VASMIR technology, TransHab, so all of those things need to be developed with R and D. Once they are available the cost of in space transit will come down by a fair amount. See Chang Diaz website.
You make a lot of assumptions here.
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k? Scale that up, would be a very cost-affordable HLV engine, yes?
My only real assumption is that comparable (both regen or both ablative, similar total thrust) Hydrolox and Kerolox engines, produced in comparable numbers will have similar costs.
The concept that an 'affordable' program involves building HLV engines in bulk seems less likely. Twenty-five Jupiter 130 launches per year would dramaticly reduce costs using existing technology, but who has 1,750 tons of stuff that needs transport to LEO? Kerolox will not change that.
As I said, forgetting about whether the research will actually be successful, what technology would reduce cost to orbit by even 20% within a 5-10 year period? The FY11 plan seems to expect a breakthrough that will alter one of the important paramters in the basic rocket equation. How else will costs be dramaticly reduced from all of the options available to us today? We have commercial access to space already. Flying people will not halve the cost per kg to orbit from what communication sattelites pay.
http://en.wikipedia.org/wiki/Deep_Space_1
http://www.adastrarocket.com/aarc/
Electric propulsion tugs could be used to efficiently pre-place propellant depots and equipment. Also, by separating cargo and crew, you can use more efficient trajectories for the cargo than you would if it has to go quickly with the crew, even if you're just using chemical rockets.
Also, in the case of propellant depots, you aren't necessarily changing the rocket equation itself, but since many small launches can be used for the propellant, a reusable tanker craft makes sense (both the on-orbit tanker and the launch vehicle can be reusable, especially for LEO depots). Reusable makes sense if the spacecraft's mission is short (the tanker spacecraft just needs to rendezvous with the depot in LEO and return, less than a week I'm sure) and many times a year (small launch vehicles, while more expensive per pound at the same number of launches per year as a larger launch vehicle, can reach above 40 launches per year for the same amount of mass in orbit as four HLV launches a year, which is firmly reusable launch vehicle territory).
Propellant depots combined with high-Isp solar-electric propulsion (slow but efficient) really does change the rocket equation, the same way that petroleum is transported by pipeline or ship or rail instead of jet airplanes, which is less than 10% as efficient per ton-mile of freight.
Are any major breakthroughs needed for SEP or Depots?
I was under the impression that the answer is no.
So why wait 5 years to begin the design?
If THAT is the POTUS's plan, then he should just say so and start designing TODAY.
I prefer Direct over Flexible EELV, but either plan seems workable without a decade worth of research. How will the RESEARCH lower the costs more than a small margin?
I agree with you arthur. And yes I saw and read Robot's post. I will be posting a thread dedicated to how we could leverage existing assets in a variety of ways to begin exploring as soon as possible, sometime soon (when I get enough time to write the whole thing).
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k?
not unless you could produce a link backing this up.
Probably a naive question, but I just gotta ask: has it ever been suggested to "capture" a very small asteroid, James Bond style (You Only Live Twice). Before you think I'm mad, I'm not suggesting actually moving the asteroid, but simply surrounding it with an inflatable shell (Bigelow style), i.e. the shell and asteroid are in the same solar orbit. Bigelow's Sundancer will be around 6m in diameter and 8.7m long, so the order of magnitude is the same as a 10 - 20m asteroid.
Then pressurise the shell and allow astronauts to work in a shirt sleeve environment?
I presume the main problem with inflatable craft is that the docking ports are not inflatable and are limited in size to the launch vehicle's diameter?
I'm starting to regret asking this question, so I'm gonna press the "Post" button before I change my mind ...
Pretty clever if you ask me. But, and this is a big but, the whole point of going out to NEOs in the first place (at least, if you ask me) is to do science. And, well, exposing surfaces that have been in vacuum for 4.5 billion years or so to air with a significant partial pressure of oxygen does not seem like it would facilitate that. Of course, most of the samples and research that will be done will be done in atmosphere, but it is at least possible to consider samples isolated in vacuum or at least helium/argon/xeon etc. atmospheres until arriving back on Earth, and then handled in nitrogen or something. And certainly at least a few scientists will want that (I would guess that most of those minerals haven't been oxidized either, which could get *real* fun).
How is the FY11 plan affordable?
...
I don't see anything that will change the Augustine Commission cost estimates, so why burn Billions of dollars with unnecessary delays and useful - but not game changing - research.
Nail on the head. It's all about promising the universe, but not committing to anything that is the slightest bit risky. It's a shallow political move from a bunch of shallow politicians.
...
Of course, with the smallest (10-20m-class) meteoroid-sized NEOs, even a 'docking' is impossible. However, larger Earth-grazers could use a landing platform.
...
Probably a naive question, but I just gotta ask: has it ever been suggested to "capture" a very small asteroid, James Bond style (You Only Live Twice). Before you think I'm mad, I'm not suggesting actually moving the asteroid, but simply surrounding it with an inflatable shell (Bigelow style), i.e. the shell and asteroid are in the same solar orbit. Bigelow's Sundancer will be around 6m in diameter and 8.7m long, so the order of magnitude is the same as a 10 - 20m asteroid.
Then pressurise the shell and allow astronauts to work in a shirt sleeve environment?
I presume the main problem with inflatable craft is that the docking ports are not inflatable and are limited in size to the launch vehicle's diameter?
I'm starting to regret asking this question, so I'm gonna press the "Post" button before I change my mind ...
Random outlandish idea I had after reading this post: What if you took three Bigelow modules and arranged them in parallel around the small asteroid, perhaps with some sort of rigid framework to keep them in place? You could then take some sort of flexible, tear-proof, and impermeable fabric (kind of like that used in the Bigelow module walls) which can be stretched between the three modules, and attach them to the modules using something akin to zippers. Once you have fabric in between all of the modules and surrounding the asteroid, you can then fill up the interior with breathable air, and perhaps have an airlock between one of the modules and the asteroid-including interior. You in essence then create a giant triangular prism-shaped inflatable habitat using the three smaller modules as corners.
Such an arrangement might also be handy for doing shirt-sleeve construction/repair of spacecraft in orbit.
It might be worthwhile to create another thread in the "Advanced concepts" section on "Off-the-wall ideas for things to do with Bigelow modules." It might also be cool to create a simple model of a Bigelow module in SketchUp to quickly portray what some of these things might look like (I'd be happy to do it if I can find some spare time).
(removed text for brevity - click on post link to see original quote)
(removed text for brevity - click on post link to see original quote)
Random outlandish idea I had after reading this post: What if you took three Bigelow modules and arranged them in parallel around the small asteroid, perhaps with some sort of rigid framework to keep them in place? You could then take some sort of flexible, tear-proof, and impermeable fabric (kind of like that used in the Bigelow module walls) which can be stretched between the three modules, and attach them to the modules using something akin to zippers. Once you have fabric in between all of the modules and surrounding the asteroid, you can then fill up the interior with breathable air, and perhaps have an airlock between one of the modules and the asteroid-including interior. You in essence then create a giant triangular prism-shaped inflatable habitat using the three smaller modules as corners.
Such an arrangement might also be handy for doing shirt-sleeve construction/repair of spacecraft in orbit.
Yes, quite outlandish
But I think you need more than three modules (apexes) to make a prism. I think what you were talking about was a tetrahedron pyramid, which has four apexes:
http://en.wikipedia.org/wiki/Pyramid_(geometry)
I don't think you need the Bigelow modules for the apexes, just the Bigelow module inflatable material for the pyramid walls.
It might be worthwhile to create another thread in the "Advanced concepts" section on "Off-the-wall ideas for things to do with Bigelow modules." It might also be cool to create a simple model of a Bigelow module in SketchUp to quickly portray what some of these things might look like (I'd be happy to do it if I can find some spare time).
Good idea, this is off-topic here. But spare time is in short supply for most of us
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k?
not unless you could produce a link backing this up.
Why, I speak of course of the X-34's Fastrac engine:
http://www.nasa.gov/centers/marshall/news/background/facts/fastrac.html
I did double check, and the goal was to hit $350k with the Fastrac.
... The knowledge used to make the Fastrac ended up being used for the turbopump for SpaceX's Merlin:
http://www.barber-nichols.com/products/rocket_engine_turbopumps/
Yup, now if only SpaceX was willing to sell Merlins to other companies.... 
That's the backup plan if they fail. Not a bad alternative, actually. EDIT: Especially if they do build the Merlin 2 engine before they fail... There's your large domestic kerolox engine. Good investment for the big boys, if SpaceX goes belly-up.
Would you believe NASA built a Kerolox engine that could, in volume production, cost under $300k? Scale that up, would be a very cost-affordable HLV engine, yes?
no, because NASA doesn't build engines
If Congress instead chooses to stretch out budgets and drop critical research then I agree with you that talk of exploring Mars by humans is a nice goal but not realistic. Your budget argument only makes sense if we abandon attempts at new strategies (prop depots, cyclers, etc.) and try to go at it Apollo style.
I agree.
How is the FY11 plan affordable?
I am not just being critical of it, but I genuinely do not see any dramatic 'cost saving' advances to be made in a 5-10 year research program (at least none that are being seriously discussed in open debate).
A new Kerolox engine will perform in the same ballpark and for the same cost as existing hydrolox engines - certainly nothing here to reduce the cost per kg to LEO by even 20%. The total number of engines built would have more impact on the cost to orbit.
I agree that there's not a lot of reason to expect a class kerolox-core system to be vastly cheaper than hydrolox. The main difference is that SSME-hydrolox (ie, SDLV, ie J-130) is use-it-or-lose-it, and we'd have to start paying the fixed costs for it now at $2-3 billion/year without payloads to use on it until late in the decade.
Super propulsions like Plasma and Ion are unsuitable for launch, thus of no impact until the 2025+ missions.
For LEO, or for deep-space? Solar-powered ion drives exist
right now: Deep Space I. VASIMR is the poster child, but more conventional ion drives and solar arrays or even solar-thermal are reasonable technologies for sending infrastructure to Mars.
The areas that COULD impact costs and ARE being discussed include EELV based Flexible Architectures and Fuel Depots. As far as I know, neither of these needs any real research.
If EELVs and Fuel Depots are the path forward, then why doesn't the FY11 plan just shift 5 years and start development right now. There are no technology 'game changers' on the horizon.
I don't see anything that will change the Augustine Commission cost estimates, so why burn Billions of dollars with unnecessary delays and useful - but not game changing - research.
You're right, that strictly speaking, cryogenic fuel transfer, depots, sun shades, and automated docking are not really "research" problems: but they are perceived as "unproven" risks to a science or HSF mission. Thus the need for (D)evelopment missions to advance the lab tech up the TRL tree, to where it can be baselined for SMD or HSF flights.
And we should start Development right now: and that's the wonderful aspect (as I understand it) of the FY 2011 plan.
-Alex
