Technologies Necessary for a Spacefaring Society

I’ve talked a lot on my blog about the various technologies that are important for a society to master before they can become a truly spacefaring society. I figured just for kicks, and in an effort to tone-down on the snarkiness and NASA-bashing that is oh-so-easy to get caught up in, I’d put up a list of what I think some of those technologies are and why. I doubt this will be a complete list, and the list isn’t in any particular order, but with that said, here goes:

  1. Reusable Orbital Transportation: I wouldn’t consider our society to be truly spacefaring until we had an off-earth population at least as high as Tehachapi, with the number of trips to orbit per day at least as high as the daily number of general aviation flights in and out of Mojave Airport. That’s a pretty darned low bar to set, but orders of magnitude more than what we’ve currently acheived after nearly 40 years. Expendables are still useful, will still be around for a while, will still be economically viable in the near to medium term, but are utterly incapable of supporting this kind of a traffic rate. When you factor everything (including third party liability insurance, manufacturing costs, launch licensing costs, etc, etc, etc), you eventually reach the point where you realize that long-term, reusability is not an option, it has to come standard. Here’s a few subtechnologies that I think will be important to master:
    • High Longevity Rocket Engines: Right now the best rocket engines in use by the big boys are only really good for 100-200 full duration firings before they start having issues (usually related to the brazing on tube-wall nozzles or mushrooming of the cooling lands for channel-wall designs). That’s a start, but really the number needs to get to at least 1000 before we’re really getting anywhere. Remember, jet engines also handle very high energy densities, high temperatures, fast moving, close tolerance parts. They also started out with lifetimes between major overhaul measured in single-digit hours. Nowadays they’ve improved substantially. I think there’s room for improvement for rocket engines too. The Chamber-Saddle-Jacket design used by XCOR, SPL, and MSS is one approach that might lead to high longevity rocket engines, but more methods that cover more of the design space need to be worked out.
    • Low-Maintenance Reusable TPS: RLVs in order to be fast turnaround really need better and more reliable Thermal Protection Systems. While there may be some mileage to be gained from quick-removable ablative panels and such, at some point a truly reusable system (whether it be radiative, regenerative, or transpiration based, or some combination of the three) needs to be fielded. Particularly one that can be tested in advance.

  2. Aerobraking: For any commerce outside of LEO, the ability to reduce fuel requirements at certain points in the trip by use of aerobraking starts becoming very important. By not having to carry all the fuel to completely propulsively brake into LEO for instance, you can get away with much smaller vehicles, a much higher amount of actual passengers or payload per amount of mass lifted out of gravity wells, and much simpler logistics and performance demands on interorbital space transports. Not to mention that they make reusing interorbital space transports a lot easier. The technologies needed here might include improved TPS designs, ways of more accurately determining the atmospheric densities along the aerobraking trajectory, and improved techniques for navigation and control during the aerobraking maneuver.
  3. On-Orbit Propellant Transfer: I bet you were wondering when I’d get back on this hobby horse. The ability to transfer propellant on-orbit is at the heart of any spacefaring society. Without the ability to refuel and reuse space transports, you’re stuck with essentially single-use throw-away systems little better than what we had during the Apollo Program three decades ago. On-orbit refueling also creates transportation nodes which tend to be the nuclei of commercial activity. It allows you to more completely disaggregate your in-space transportation systems from your earth-to-orbit systems. Combined with other techniques like On-Orbit Assembly and On-Orbit Construction, you can create almost any sort of transportation infrastructure imagineable.
  4. Long-Term On-Orbit Propellant Storage: While being able to transfer propellants to orbit is important, the ability to store propellants (especially cryogens) for long duration with low or no boil-off is also very important. This makes propellant depots, propellant tankers, and other such things viable. Much as “coaling stations” made rapid oceanic transportation viable on earth, propellant depots throughout manned space will also play a key role in enabling interplanetary commerce.
  5. On-Orbit Assembly: The ability to routinely and affordably assemble prefabricated structures on orbit, whether they be satellites, stations, or even vehicles is also very useful. It allows you to build things on-orbit that would be too big volume or mass-wise to easily loft on a single earth-to-orbit booster. Big boosters start really running into some serious issues after a certain size (like how to physically handle something that big, noise levels, developing massive engines, etc–at some point you will want to do something too big to fly even on a dozen Saturn Vs–deal with it). People like to talk about how much more expensive it costs to do anything in space compared to a factory floor on earth. But when you include the cost of building/operating a booster big enough to avoid having to build stuff in space, it starts looking really wise to attack the cost of working in space instead of continually trying to build bigger and bigger Uber-Launchers.
  6. On-Orbit Construction: You’re going to reach a point where you want parts with contiguous volumes bigger than can be safely launched on the biggest boosters, and possibly bigger than can be handled on the biggest boosters with inflatable structures. Things like dry-docks for building/repairing/overhauling/maintaining other vessels, very large propellant tanks, cycler ships, zero-G arenas, space habitats, etc. Just as with on-orbit assembly, you’re eventually going to want to do something big enough that the cheapest way to do it is going to be fabricating it in space. That means shipping up smaller pieces, and actually welding or riveting or bonding them together. Maybe even going so far as shipping raw materials there and having mini-mills produce sheet and plate and structural members. Tinker-toy construction can get you a long way, but at some point you’re going to want to go with something more substantial, and figuring out how to do that sooner, rather than later, will lower the cost barrier that you have to overcome to do stuff like that.
  7. Closing the Water Loop (Or at Least Getting Close): One of the big consumables for manned spaceflight is water. There have been plenty of ideas for closing the water loop, by recycling water from respiration, laundry, dishes, showers, excratory fluids, etc. These need to be fleshed out. Even though the cost of transportation needs to go down a whole lot for any of this to become feasible, attacking the water loop is one of the highest gain-to-effort ratio tasks out there.
  8. Extraterrestrial Navigation: Right now things like GPS make terrestrial navigation very easy. For a truly spacefaring society, something like the XPPS technology I wrote about a few months ago would be very helpful. Also a system of low-cost navigational satellites, ground stations, etc througout the regions of manned activity might also be very helpful.
  9. Low-Maintenance Space Nuclear Power: While there are many areas in the solar system where solar power is adequate, there are also a whole bunch of areas where it isn’t. Space Nuclear Power gives a spacefaring society the flexibility it needs to be able to access places that otherwise would be very difficult. A society that hugs tiny slivers of the moon because it can’t otherwise handle the nightspan electricity generation can hardly be called truly spacefaring (though it’d still be a step-up from where we are now).
  10. [Update:

  11. Space Tugs: Clark made a fairly good point about the idea of space tugs. Basically, like in CSI’s preferred station delivery method, you have the brains and docking system in the tug, allowing the bigger vehicles to not have to have as fine of guidance and docking equipment. This also allows you to deliver dumb cargoes to a safe distance from the station, and have the tug bring them in for final docking. Lastly, it also allows you to launch the payloads into a lower parking orbit, and then have the tug swoop down and get it. You’d be surprised how much more efficient that can end up being, particularly if the station is at a moderately high altitude (to avoid drag or other issues). Since the tug is at a shallower part of the delta-V curve, just a little bit of propellants goes a much longer way than for the orbital vehicle that is already at the very, very steep part of the curve. There’s a reason why tugboats are used so much in modern ports–they just make sense.]
  12. [Updates #2 and 3:

  13. In-Situ Resource Utilization: This one was so obvious I forgot to include it. Basically, if you don’t know how to extract resources off-planet, you’re not a spacefaring society. In fact, many of the reasons for going off-planet in the first place almost inherently assume some level of ISRU. The most important near term ISRU technology being ISPP or In-Situ Propellant Production. Once you can get propellants produced off-planet, you no longer have to ship them all the way from home. That allows your transportation network to become amazingly more efficient fast. Basically, it allows you to “reset the Delta-V curve” frequently, which keeps you from needing super-high mass fractions anywhere, which makes construction, maintenance, etc of vehicles a lot easier. Once we have ISRU fed propellant depots on the lunar surface, in LUNO or at L1, on the Martian Surface, and in Mars Orbit, transportation between the Earth, Moon, and Mars will become substantially cheaper. Even idea’s like Elon Musk’s one-way mars colonists could benefit from fueling stations in orbit and on the surface. That makes the landers reusable, which drives that cost down and reliability up (remember, landing almost anywhere off earth requires VTVL, with most places not having any abort modes–your lander has to be rock-solid reliable, and the best way to guarantee that is by making it reusable, testing the heck out of it on earth, then testing the heck out of it on Mars once it gets there). If combined with a tug, it also allows you to pick how aggressive your aerobraking is, whether it is just aerocapture, with a tug bringing you the rest of the way in, or out-and-out aerobraking. Plus, if the ship can be sent back to earth, and reused, the capital cost for that goes down too. Not to mention you’re going to have at least some colonists pansying out, and you’re going to want at least some level of commerce going on even for a “self-sufficient” colony (true self-sufficiency is a really dumb idea unless you have absolutely no other choice).
  14. Artificial Gravity: By this I mostly mean spinning stations up and stuff to get artificial gravity from centrifugal accelerations. The sooner we figure this one out the better. Right now, we have no idea what the health vs gravity curve looks like. We only have two main data sets, one at microgravity, and one at full Earth gravity. For all we know you can get sufficient fluid settling by 1/20th of a G to avoid the most severe of the microgravity health deterioration issues. Or it could require 19/20ths. We flat out don’t know. Variable gravity techniques like the xGRF station that Kirk mentioned in comments would go a long way to resolving that. Once we know what the curve looks like, making stations that actually take advantage of artificial gravity will allow people to live on-orbit in a lot more convenience. It also simplifies a lot of the life support problems that exist from having a microgravity station. I’m sure there’ll still be plenty of microgravity research stations or free-flyers. It’s just that I think that most of the transportation nodes or industrial facilities will have sizable artificial gravity sections even if they also have a non-spinning zero-G area.]

Anyhow, as I said, this list isn’t exhaustive, and I tried to mostly stick to stuff that could be done today, as opposed to longer-term (or more dubious) stuff like carbon nanotubes, self-replicating robots, nuclear fusion, nuclear propulsion, etc.

These are the kinds of technologies that I think NASA would be better off developing than merely pursuing an old-school Apollo rehash. Unlike today’s NASA, NASA in the age of Apollo had the balls to actually try new things and develop technologies where it made sense and where it made the goal easier. At the start of the Apollo program, we had zero experience with things like orbital rendezvous and docking, but instead of pansying out, NASA went and developed the expertise. Today’s NASA seems to be trying to go back to the moon without actually developing any of the near-term feasible technologies that would actually allow it to do something substantially more useful and relevant than what we did thirty-some-odd years ago. Instead of spending billions of dollars trying to “fill a much needed gap in US space transportation capabilities”, NASA would accomplish a whole lot more if it spent at least some of that money on developing one or two of the above technologies first. Instead of spending $5B on yet-another-medium-lift-expendable, they could borrow a page from the DoD, tell ATK that it’s going to have to put some skin in the game, and use some of the freed up money to demonstrate on-orbit refueling. Maybe use $1B to fund two “big boys” to do it the “business as usual” route, and use another $.5B doing a more commercial approach.

At the end of the decade in addition to a worthless medium lift booster that it would already have, NASA would likely have two or three good methods to pick from for orbital refueling, developed to the point that the rest of the Project Orion could take advantage of it. With several commercial companies and the EELVs and the Stick all able to launch propellants and exploration components, that might allow NASA to avoid needing to develop a separate HLV, and go directly to a reusable EDS. That’d save a lot of money, expedite the program, and allow for a much more substantial program with a much higher probability of expediting the beginning of commercial utilization of cislunar space. The stuff that the guys at MSFC and JSC could work on at that point would be really, really exciting. Possibly the kind of stuff that’d get people wanting to work for NASA again.

Or they could just treat this as a welfare program for aging rocket nerds. Unfortunately you can guess what’s most likely to happen.

Any thoughts, additions, etc?

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Jonathan Goff

Jonathan Goff

President/CEO at Altius Space Machines
Jonathan Goff is a space technologist, inventor, and serial space entrepreneur who created the Selenian Boondocks blog. Jon was a co-founder of Masten Space Systems, and is the founder and CEO of Altius Space Machines, a space robotics startup in Broomfield, CO. His family includes his wife, Tiffany, and five boys: Jarom (deceased), Jonathan, James, Peter, and Andrew. Jon has a BS in Manufacturing Engineering (1999) and an MS in Mechanical Engineering (2007) from Brigham Young University, and served an LDS proselytizing mission in Olongapo, Philippines from 2000-2002.
Jonathan Goff

Latest posts by Jonathan Goff (see all)

Jonathan Goff

About Jonathan Goff

Jonathan Goff is a space technologist, inventor, and serial space entrepreneur who created the Selenian Boondocks blog. Jon was a co-founder of Masten Space Systems, and is the founder and CEO of Altius Space Machines, a space robotics startup in Broomfield, CO. His family includes his wife, Tiffany, and five boys: Jarom (deceased), Jonathan, James, Peter, and Andrew. Jon has a BS in Manufacturing Engineering (1999) and an MS in Mechanical Engineering (2007) from Brigham Young University, and served an LDS proselytizing mission in Olongapo, Philippines from 2000-2002.
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53 Responses to Technologies Necessary for a Spacefaring Society

  1. Brian Dunbar says:

    You forgot Moon Maidens. They’re pretty darn necessary, in my humble opinion.

  2. Jon Goff says:

    Brian,
    Moon Maidens? I don’t think any of the gals I’ve ever dated/previously been interested in could be classified as “technology”… 😉

    But if we were talking about “things” necessary for a spacefaring society, you might have a point….

    ~Jon

  3. Anonymous says:

    Thought you might like this link:
    http://www.engadget.com/2006/08/23/south-koreans-make-hydrogen-solid-for-a-brighter-fuel-cell-futur/

    Seems that storage of Hydrogen without cryogenic temperatures is becoming feasible.

  4. kert says:

    I’d submit that at least in-space power beaming would be a “nice to have” as well

  5. kert says:

    Now actually thinking about it a bit more, you probably have to split this list in two. Technologies that deal with transportation, and technologies necessary for human survival and sustainable operations.
    Closing the water loop belongs in the second category.

    For transportation, moment exchange tethers would also be a “nice to have”

    For sustainable operations on surface (roids, moon, mars ) ISRU will become a necessity.

  6. Monte Davis says:

    Good list. I second kert on tethers, both momentum-exchange and electrodynamic, which could lower the cost of LEO->GEO as well as other orbital changes. They’d also add to the knowledge and experience base needed for a “beanstalk” space elevator down the road, if progress in CNTS were to make that feasible.

    For human spaceflight, we also need to start getting some experience with centrifugal gravity. (Consider that YA tether application, if you like.)

  7. Jon Goff says:

    Kert, Monty,
    I agree with you guys on ISRU and artificial gravity. However I think that the tether stuff is too early to tell. Particularly, I’m not sure it’s really “necessary” for a spacefaring society. You can have a sophisticated spacefaring society without them. More to the point, I have some real questions about the scalability of MXER tethers. They sure look good for very low flight rates, but at some point really soon, you start having to have so many of them that I wonder if it’s really practical to have that many whirling tethers o’ doom flyin’ around there in orbit. I could be wrong, but I’m mildly skeptical at the moment.

    Now, using Electrodynamic tethers for reboost, using tethers for a variable gravity space station, or using tethers for gravity gradient propellant settling…those are less pie-in-the-sky to me, but you could still have a good spacefaring society without any of them.

    ~Jon

  8. Anonymous says:

    Simpler and more robust spacesuits would also be useful, although they might be better put on a secondary list of *very useful* support technology. Spacewalks would be a lot easier and more productive if the suits were (1) easy for one person to put on and put off, (2) didn’t require pre-breathing, (3) require very little maintenance, and (4) had better gloves. The current Russian suit dates back to their moon program. The US suit dates back to the early shuttle program. They both have problems.
    — TomD

  9. Anonymous says:

    I think that tethers are a very important technology.

    One thing to keep in mind about a MXER tether is that as long as there is the same mass going down as up, it will need almost no energy, so it could handle multiple payloads per day.

    Many kinds of travel such as tourism are both way anyway. And if there is a need for additional downmass, you can always dig up some moon dirt.

    Sooner or later there would be some kind of stock exchange trading momentum.

  10. Jon Goff says:

    Anonymous,
    Regarding MXER tethers, I guess I’m just not a fan of high-speed precision rendezvous like that. It’s non-trivial, and if you screw up, your MXER tether is thrown off. If you’re using one for say cis-lunar transportation, that means you have to hit a pinpoint target on the first pass from a very long distance. And if you miss, it’ll screw things up for every other payload that is “in the queue”.

    Not unsolveable problems, but once you’ve gone through all the effort to solve them, it’s no longer as big or obvious of a win.

    ~Jon

  11. Neil H. says:

    Not to be nitpicky, but “maintances” should be spelled “maintenance.” I thought it might be worth mentioning since it’s one of your bullet-items.

  12. Neil H. says:

    Also, what about radiation shielding? (this was mentioned at a community I posted to)

  13. kert says:

    The most important near term ISRU technology being ISPP or In-Situ Propellant Production.
    I would submit that power production using in-situ materials is even more near-term and even more important.
    In short, lunar-produced solar cells. The tech is fairly well developed (google: lunar Ignatiev Freundlich) , whats missing is a pilot project.

    The reasoning here is that every process, and ESPECIALLY cooking volatiles out of the rocks requires plenty of power, expanding power using in situ materials enables immediate growth in capabilities without extra launch mass.

  14. Kirk Sorensen says:

    Jon, a miss on a MXER tether doesn’t “screw it up” for any other payloads. It just means you have to go try again. The dynamics of the tether and payload are specifically chosen to enable this. Furthermore, some really amazing astrodynamics work was done at NASA recently that showed that MXER tether rendezvous could be accomplished, and quite well at that.

    The twin breakthroughs were a revolutionary orbital propagation algorithm that told you where the tip of the tether would be, even accounting for all the disturbances and dynamics, and a “catch mechanism” design that accommodated for errors in position and velocity right before rendezvous.

  15. brian d says:

    I didn’t see your article on XPPS at the time, but I disagree with extraterrestrial navigation being any sort of problem. Right now you pay about $75k for a star tracker then about twice that amount on test and integration (much of which I think is a waste). Together with a wide angle sun sensor (WASS) navigation is simple and precise. I don’t believe any improvement is necessary much less “key”. Having said that, I won’t disagree that we could stand to have substantial reductions in cost.

  16. baikonur says:

    Hydroponics or some sort of sustainable off-planet agriculture. Until we can tackle the ability of growing/producing our own food off-planet, we will always be tethered to earth.

  17. Alex says:

    More robust spacesuits is a great one.

    How about telecom relay infrastruction around Mars and Moon (like the cancelled Mars Telecom Orbiter, but on a much larger scale), as well as global weather monitoring satellites, ground stations on Mars.

  18. Bill White says:

    Regarding MXER tethers, I guess I’m just not a fan of high-speed precision rendezvous like that. It’s non-trivial, and if you screw up, your MXER tether is thrown off.

    JDAMS feature “warhead to forehead” rendezvous and the foreheads are usually seeking to evade.

    Tether rendezvous is “forehead to forehead” and is tricky but with two computers seeking to make the connection, should be doable.

    Didn’t NASA fly a spaceprobe on a multi-year mission and landed it at a precise spot in Utah – without propellant? Okay, the helicopter missed the catch, but still . . .

  19. Jon Goff says:

    Brian D,
    You may be right, I may be overestimating the problem.

    ~Jon

  20. Sam Dinkin says:

    This is an engineering list. A more comprehensive list would look further afield to governance, legal, management, economics, etc.

    http://www.thespacereview.com/article/317/1

  21. brian d says:

    Bill White said…
    Didn’t NASA fly a space probe on a multi-year mission and landed it at a precise spot in Utah – without propellant? Okay, the helicopter missed the catch, but still . . .

    A painful memory I’d like to forget. Genesis, the parachute didn’t deploy so the helicopter didn’t even have a chance. 250 mph right into the Utah mud, but it was right on target 10s of millions of km and missed by less than a km.

  22. Jon Goff says:

    Sam,
    Yeah, as the title says, I was just looking at the technological dimension for this post. There are plenty of other things that are important (most important being proving out actual marketable goods and services), I was just trying to point out that there were several key technologies or techniques that we needed to figure out.

    ~Jon

  23. Mark says:

    This list has a lot of neat technology which is likely useful. However, tasking NASA to develop all of it before going to the Moon is sort of like telling Lewis and Clark not to head west until the interstate highway system is completed.

    A better idea would be to go ahead with ESAS, get people on the Moon, then set up commercial competition in the private sector to sustain them, in part, by creating some of these neat technologies. And let it be their choice as to what gets created. Policy should be focused on the goal, not on technological toys.

    By the way, Sam is right. A good international regime protecting private property rights on the Moon would be far more important than having another vapid argument over the Stick vs EELV.

  24. Jon Goff says:

    Mark,
    I saw your post earlier, but have been too busy at work to reply. I’ll get to that when I get home.

    ~Jon

  25. Michael Mealling says:

    Mark,
    The flaw in your “just put some people there and then figure it all out” approach is that you end up with an infrastructure built simply to sustain 3 guys on a government payroll with no real reason for being there. What Jon is suggesting is that NASA should go back to a more NACA like approach and figure out the hard problems so that it becomes cost effective for others to do things in space for other motivations.

    Simply “get people on the Moon” isn’t remotely sustainable with the American tax payer. Been there. Done that. *Yawn*

  26. murphydyne says:

    Yeah, I saw Mark’s comments as well, but he lost all credibility with me when he asserted that “The goal, gentle readers, is to send people back to the Moon.”

    So of course I go to my bookshelf and pulled out my copy of the VSE. Stated under Goals and Objectives is:

    “The fundamental goal of this vision is to advance U.S. scientific, security, and economic interests through a robust space exploration program.”

    Nothing about the Moon in there. That doesn’t come until bullet number two. Bullet number one is especially interesting: “Implement a SUSTAINED and affordable human and robotic program to explore the solar system and beyond;”

    I also note that the title if the document is “A renewed Spirit of Discovery: The President’s Vision for U.S. Space Exploration”. It IS NOT “NASA Space Exploration”, it IS about the United States, and our nation’s science, security, and economic interests in the realm of space endeavours.

    Jon is talking about a sustainable architecture, because he’s talking about the infrastructure elements that support people doing commerce. ESAS does not provide any infrastructure elements that can be used by commercial interests:
    -No private company could afford the insurance of launching their employees on the shaft.
    -No private company can use the proposed heavy lift vehicle. It’s impossible right now to amass that tonnage of commercial assets on a single vehicle and be able to find adequate insurance for it.
    -No private company can buy an LSAM. Most of what you buy is thrown away (in space no less, where you can’t get to the rubbish for reducing, reusing, recycling!), making it not very cost effective.
    -No private company is going to buy a CEV vehicle that can only be launched on a single vehicle. STS has shown how bad that be.

    In fact, I would argue that Mark’s assertion that the “ESAS program…will put a small group of people on the Moon on a more or less permenent basis” is pure fantasy. Why should our nation proceed in a way that has been demonstrably shown not to work, that of relying on a single vehicle. Were the ISS still SSF, and relied entirely upon the shuttle for its permanence, I think it highly likely that it would have gone the way of Skylab by now.

    If I were a young man entering college, I might be inclined to go into engineering to work on the kinds of projects Jon has outlined. Going into engineering so that I could go on archealogical digs of Apollo hardware to redo it (but better!) sounds much, much less appealing.

    I guess my additions to the list would be cislunar traffic control and more modularity in the transport architecture, in the context of:
    -Lunar lander legs added/removed at L-1.
    -Heatshields for Earth return attached in LEO.
    -standardization of interfaces between the pieces.
    -some standardization in propulsion modules, where they might be rated by dV, but could still be attached to the same interface.
    -waldoes added at L-1 for GEO runs.
    -six-sided universal docking nodes for cobbling together different elements for longer term missions (like to NEAs).

    Great list Jon! Have you ever thought of cobbling some of this stuff together and publishing “Jon’s Guide to Real Space Development”?

    Oh, and I agree on the hydroponics/greenhouses. Great technology that the U.S. is already way ahead of the curve in.

  27. Bill White says:

    -Lunar lander legs added / removed at L-1.

    Encourage Masten to win the Lunar Lander Challenge. That would be a very valuable step towards a re-useable LSAM. Then the landing legs can remain 4 down and welded at all times.

    As far as I can tell, NASA is holding off locking in the LSAM design until they learn whether folks like Masten or Armadillo or whoever can do re-useable LSAM engines. Which is altogether good.

    A re-useable LSAM combined with lunar LOX would greatly lower the cost of lunar access.

    = = =

    Using a Dnepr or Falcon 1 and with corporate (advertising) sponsorship perhaps a Masten lunar lander can deposit small payloads on the Moon far sooner than anyone may currently be thinking – – a few years, perhaps?

    Or land a giant billboard with an on board camera, for example, paid for by an advertiser willing to bet on a Masten lander.

  28. Joe says:

    I thought that some structure might help.

    Getting there
    * Reusable Orbital Transportation:
    ** High Longevity Rocket Engines
    ** Low-Maintenance Reusable TPS

    Traveling there
    * Space Tugs
    ** Long-Term On-Orbit Propellant Storage
    *** On-Orbit Propellant Transfer
    ** Aerobraking
    * Extraterrestrial Navigation

    Earning money there
    * In-Situ Resource Utilization
    ** On-Orbit Construction
    *** On-Orbit Assembly

    Living there
    * Closing the Water Loop (Or at Least Getting Close)
    * Low-Maintenance Space Nuclear Power
    * Artificial Gravity (e.g. centrifugal acceleration)
    * Radiation issues

  29. Pete Lynn says:

    A couple of additions I would make:

    Mostly forget space suits, instead develop a very small rigid one person tug vehicle with multiple robotic arms – looks a bit like a submersible but based on a pressure cylinder just large enough to hold a person. It should be not much heavier and much more robust – no pre breathing required and can function as an emergency orbital transport vehicle, inflatable pod attachment? It might also avoid the need for a separate airlock – fast response, and even be tele-operated. The intent being that anything that needs detailed hands on work could then be quickly removed and passed inside the vehicle or returned to a hanger – which would make the work much easier. Detailed hands on work should not be done outside, unless absolutely critical. A generic robotically armed person carrying tug which has the capacity to have all sorts of mechanical attachments added is needed.

    Thermal power systems. With the likes of the Moon and Mars a large concentrator combined with a large tank of regolith for night time thermal energy storage sounds much easier than a nuclear reactor. Both systems would need a similar thermal engine and cold end heat exchanger anyway – the massive parts. On Mars one might have the concentrator collapsible so as to survive strong winds. Mass wise I would expect a concentrator plus regolith tank to be lighter than a reactor, easier to launch, and easier to repair and grow with insitu resources. Such a system can incrementally grow into a substantial long term sustainable power source, easily scaleable.

    Low delta v momentum exchange tethers. A 500m/s rotovator in LEO would be relatively unchallenging yet would still save huge amounts of propellant. Required tether mass is similar to payload mass – low mass system with low accelerations and tether lengths. Even at this low delta v launch vehicle payload to LEO would be near doubled. It seems to me the economics of this are so attractive that it is worth doing this from near the start – this is an approach that can actually lower the cost of space infrastructure development. It would also only take three or four such small tether systems, staged, to get to the Moon or Mars.

    Automated greenhouses for staple food production and volatile recycling, spinning habitats, hangers, etcetera, are all way up the list. Another thing that I have been considering is a good cold end radiator constructed of many very small diameter inflatable tubes that are self repairing or easily repaired/replaced. This would double as impact shielding. Photosynthesis is very inefficient and greenhouses especially will require huge radiators or surface area that will just not be easy to shield, hence the small diameter redundant continuous repair approach. Such a radiator system is also desired for heavy industry, large habitats and solar thermal power generation – where heat rejection will be a big problem. The need for low mass, cheap, impact resistant heat radiators will I expect quickly become a significant problem.

  30. Bill White says:

    I agree these lower costs:

    Earning money there
    * In-Situ Resource Utilization
    ** On-Orbit Construction
    *** On-Orbit Assembly

    Yet how do they earn money?

  31. Bill White says:

    I fully concur with this idea:

    Low delta v momentum exchange tethers. A 500m/s rotovator in LEO would be relatively unchallenging yet would still save huge amounts of propellant. Required tether mass is similar to payload mass – low mass system with low accelerations and tether lengths. Even at this low delta v launch vehicle payload to LEO would be near doubled. It seems to me the economics of this are so attractive that it is worth doing this from near the start – this is an approach that can actually lower the cost of space infrastructure development. It would also only take three or four such small tether systems, staged, to get to the Moon or Mars.

    However, since the deployment of tethers will lower launch costs without the need to build honest-to-God spaceplanes, expect resistance.

  32. Kirk Sorensen says:

    I would suggest Earth-Moon L2 instead of L1 as a staging point. It can be achieved for much less delta-V than L1 if a powered lunar swingby is used. It also makes an excellent departure point for Mars vehicles. High-thrust Mars vehicles can leave L2, do a lunar swingby to enter a highly-elliptical lunar orbit, and then do the trans-Mars injection burn at perigee. Low-thrust Mars vehicles can leave directly from L2 with only a few days of “spiral-out”.

  33. adiffer says:

    I’ve usually thought of water as being in two loops. There is the obvious one regarding life, but the other is for generating electricity. Each loop needs to operate like a stil-suit.

  34. Pete Lynn says:

    Bill White wrote: “However, since the deployment of tethers will lower launch costs without the need to build honest-to-God spaceplanes, expect resistance.”

    Reducing delta v requirements slightly probably works more to the advantage of a reusable as opposed to expendable launch vehicle – the margins becoming easier. So I think tethers actually promote the development of “spaceplanes”.

  35. Brian Dunbar says:

    Pete Lynn So I think tethers actually promote the development of “spaceplanes”.

    And a lot of other infrastructure. Reduced transaction costs for transportation always have secondary effects beyond the immediate application.

    Jon Goff However I think that the tether stuff is too early to tell. Particularly, I’m not sure it’s really “necessary” for a spacefaring society. You can have a sophisticated spacefaring society without them.

    I agree with Jon. However getting from here to there is by conventional means is just as long a step as by using tethers.

    I’m a big fan of whatever is practical and works. I have an interest in the tether side of things (smile) but I don’t demand that the universe conform to my notions of what is right.

  36. Pete Lynn says:

    I am sure most will agree that in the long term rotovators make a lot of sense. The question I have been increasingly contemplating this last year or two is whether a combined LEO rotovator plus reusable launch vehicle system can have a lower development cost than a pure reusable launch vehicle. That is, can a simple low delta v rotovator save more in reusable launch vehicle development costs than said rotovator costs to develop and deploy?

  37. Bill White says:

    I’ve usually thought of water as being in two loops. There is the obvious one regarding life, but the other is for generating electricity. Each loop needs to operate like a stil-suit.

    For power purposes, hydrogen and carbon loops can overlay each other.

    CH4 + 2 02 = C02 + 2 H2O

    Reverse as needed. Methane may be an easier energy storage medium that elemental hydrogen.

    On the Moon, oxygen is readily available perhaps even using passive solar thermal (pyrolysis).

    Cracking H2O (long term) will require local power. Short term, it may be cheaper to ship LiH to Luna to crack that H2O and free up the hydrogen. LiH + H2O ==> LiOH + H2 and the reaction is exothermic. No energy input.

    LiOH is a CO2 sorbent and will liberate H2O. Lithium carbonate is an anti-depressant. 🙂

    Why ship LiOH as a CO2 sorbent? Ship LiH and get the oxygen from Luna and crack some water at the same time.

  38. Anonymous says:

    There have been plenty of ideas for closing the water loop, by recycling water from respiration, laundry, dishes, showers, excratory fluids, etc. These need to be fleshed out.

    Several of these are in use on ISS. Urine and respiration water recycling is now routine. The others are on NASA’s wish list for bases and some R&D has been done, but it keeps getting pushed off for budget reasons.

    One other miss:
    (partially) closing the food loop. Growing food in efficent ways is key for permanent bases. The food crops can help with closing the water loop and help with air revitalization.

  39. Joe says:

    Earning money there
    * In-Situ Resource Utilization
    ** On-Orbit Construction
    *** On-Orbit Assembly

    Yet how do they earn money?

    Earning money is a little too terse. I was trying to imply that they are steps to a space based economy.

  40. Anonymous says:

    Could I suggest that a wiki might be a good location for this ongoing discussion, and the creation of a hierarchy. There must be a wiki somewhere that would be willing to host the compilation of this dialogue.

  41. Mark says:

    Michael and “Murphydyn” make assertions and expect them to be taken as fact without an iota of supporting evidence.

    Michael states, ” Simply “get people on the Moon” isn’t remotely sustainable with the American tax payer. Been there. Done that. *Yawn*”

    He forgets that what he might find boring is not necessarily so for other people. Most polling dating shows wide public support for sending people back to the Moon. Remember that most people alive today were not alive in 1969.

    “Murphydyn” states “In fact, I would argue that Mark’s assertion that the “ESAS program…will put a small group of people on the Moon on a more or less permenent basis” is pure fantasy. Why should our nation proceed in a way that has been demonstrably shown not to work, that of relying on a single vehicle.”

    This is not only a strawman, but missing the point of my proposal. I want to expand means of sending people and cargo to and from the Moon. But that’s not going to happen unless there is a market for doing so, i.e. a lunar base. Build the lunar base, even in the “horrid” NASA way, and then throw it open to private industry. It would be the equivilent of the air mail in nurturing a space commercial sector and, by the way, enabling the commercial development of the Moon.

    Jon’s idea is a nonstarter. What we we could, if it were implemented, is at best a lot of neat technology, at great expense, without a way to use them. It is building the cart before the horse. It is approaching technology development as an end and not a means to an end. Build the lunar base first, then use it to enable the technology. In any case, private business will be better positioned to figure out what toys to build that will be useful than a government agency.

  42. Jon Goff says:

    Mark,
    I think there’s a bit of confusion about what I was recommending. I’ll see if I can get some time later on to clarify what I meant, because you appear to have understood what I said differently from how I intended. Right now though, I’m at work, trying to do propulsion design. If I get a chance tonight I’ll see what I can put together.

    ~Jon

  43. Bill White says:

    Anonymous called for a wiki on this topic. A “Scoop” site with user enabled comment threads might work as well.

    One space themed Scoop site I know of is run by the Space Frontier Foundation at:

    http://www.frontierfiles.org/

    Post a diary there and registered uses can comment with threaded discussion. Maybe I should get right on that.

    Perhaps tonight unless someone beats me to it.

  44. Bill White says:

    Scoop diary posted here

  45. murphydyne says:

    Mark, you stated:

    “ESAS program that will put a small group of people on the Moon on a more or less permenent basis”

    I argued:

    “This is pure fantasy.”

    and questioned:

    “Why should our nation proceed in a way that has been demonstrably shown not to work, that of relying on a single vehicle.”

    How is this a strawman? I put no words in your mouth. I did not mis-state your position. I quoted you. A direct quote from your website.

    Where is the strawman?

    And then the shilling continues here with “But that’s not going to happen unless there is a market for doing so, i.e. a lunar base. Build the lunar base, even in the “horrid” NASA way, and then throw it open to private industry.”

    Were that it was that simplistic. So NASA’s going to build a base on our Moon that no one else can get to, and say “Here private industry, look, we built a small workshack that we want to give you. You can’t get to it, but you can have it once you figure out a way.”

    Yeah, that’s going to fly. Rather than partnering with the American people to go to the Moon in a robust and sustainable way, NASA wants to just be pathfinders. But pathfinders are no good if those who follow have to rediscover the path.

    (P.S. This is exactly what NASA did with the STS’s external tank component. They’ll carry it up to space, if you show that you can utilize it. Of course the only way to do so is to use the shuttle as your initial base of operations. Chance of arranging to do so? Very, very close to zero. I always wanted to put a belt of ion engines around the middle and boost it slowly up to a higher orbit. But you would have to carry the belt and engines in the shuttle bay. Oh well, too bad, we did offer though…)

    The Lunar Base is not a market. It is an asset. I can’t just give you an airplane and say “Look! You have a market!” No, you have an asset. And since it’s due for its ‘D’ check it’ll probably end up parked in the desert. By conflating the two you’re making a poor economic argument. And that’s a big component of why your continued championing of the ESAS, Mark, rings so hollow with me.

    Oh, and it’s murphydyne, as in a unit of Murphy force, and a tribute to the great American pioneers Astrodyne, Rocketdyne, Yoyodyne, etc. Not murphy din, though that is a cute jeux de mot.

  46. Mark says:

    Murphydyne states: “Were that it was that simplistic. So NASA’s going to build a base on our Moon that no one else can get to, and say “Here private industry, look, we built a small workshack that we want to give you. You can’t get to it, but you can have it once you figure out a way.”

    No one else can get to? So no one else but NASA can get to the lunar surface (which is where a lunar base would be located)? That’s not a rational statement. What this means is that there can be no private sector development of the Moon–ever. Why this is being asserted, I’m not sure.

    Nor does Murphydyne understand what is being proposed. No one is proposing that someone *give* anyone a NASA lunar base. The proposal is to contract out to private business the servicing of the lunar base.

    “Yeah, that’s going to fly. Rather than partnering with the American people to go to the Moon in a robust and sustainable way, NASA wants to just be pathfinders. But pathfinders are no good if those who follow have to rediscover the path.”

    Huh? That statement makes no sense.

    “(P.S. This is exactly what NASA did with the STS’s external tank component. They’ll carry it up to space, if you show that you can utilize it. Of course the only way to do so is to use the shuttle as your initial base of operations. Chance of arranging to do so? Very, very close to zero. I always wanted to put a belt of ion engines around the middle and boost it slowly up to a higher orbit. But you would have to carry the belt and engines in the shuttle bay. Oh well, too bad, we did offer though…)”

    So private business can’t get to LEO either. I guess COTS is a lie and a fraud too.

    “The Lunar Base is not a market. It is an asset. I can’t just give you an airplane and say “Look! You have a market!” No, you have an asset. And since it’s due for its ‘D’ check it’ll probably end up parked in the desert. By conflating the two you’re making a poor economic argument. And that’s a big component of why your continued championing of the ESAS, Mark, rings so hollow with me.”

    Actually a thing can be a market and an asset as well. The rest of the statement in incoherent drivel.

  47. kert says:

    duh, for all the talk about NASA’s lunar base there is scant little official info available on it. Mark can you enlighent us perhaps on what its going to consist of, where its going to sit at etc? In short, what wonderful properties and mechanics this “market for private sector” is going to have ?
    So far, most of official NASA plans i have heard of deal with the getting there part. In fact, AFAIK, most of the ESAS budgetting so far deals almost only with the getting there part.
    Maybe we should take this discussion elsewhere though, to keep this thread on topic.

  48. Bill White says:

    kert, if interested, here you go:

    LINK

  49. Rockets4Real says:

    Great topic. NASA recently had a major project to develop technologies need for exploration under the leadership of John Mankins. I spent many months developing a prioritized list of technologies for our company to invest in hopes of future contracts with NASA (some of the technologies were outside of our expertise, such as remote medical care). We were very successful in answering the Human & Robotic Technologies (H&RT) RFP. This program would have funded a sustained technology development effort at ~$1B/yr, half of the work being conducted by universities and NASA, half by private/public aerospace companies.

    That was two years ago. NASA has a new administrator and he made some organization changes. Mankins was forced out. Mr. Griffin needed most of the H&RT money to pay for the CEV/CLV (aka Shaft), and proceeded to shut down the majority of the 118 non-NASA projects (not sure how many NASA awarded projects survived).

    It would seem that NASA believes that they can not afford a broad H&RT like effort and will build the first phase of ESAS using mostly existing technology. Because NASA will not have any money for ESAS phase 2 (LSAM/EDS/Ares V) for many years (2012?) when they can get started they again will have no time for technology development and will have to use existing technology then too. I can see this dynamic occurring again when it comes time to build a lunar habitat and infrastructure. I believe this is a broken model and not in the best interest of our country and does not embrace the spirit of the VSE.

    We did have our chance! NASA chose a different path.

    The list of technologies captured so far is hitting all the high priority needs except for a few.

    Radiation Protection: This may be the single biggest engineering problem there is in space. GCR’s cosmic radiation (GCR), and solar particle events (SPE) are very debilitating and can be deadly. At L1 or on the Moon SPE’s are major risks which must be shielded for. Mass shielding in orbit would be extremely expensive without an elevator/tether available. Mass shielding on the moon would be a given. Travel beyond the Moon and you will be in space for a long time, a trip to Mars will take ~300-500 days round trip using chemical propulsion. Protecting the crew with water shielding around their hab-module is possible (heavy) but I believe this leaves the water un-potable.

    Space Power: I strongly advocated the use of small fission reactors with liquid metal cooling/energy transfer. Learn how to do this on the Moon so you can take the technology to the outer solar system. The problem is that our country is rapidly losing the capability to develop this technology. For all practical purposes the US Navy’s NR group are the only ones with that capability – and you could argue that they do not know liquid metal cooling.

    Nuclear Thermal Propulsion: If we are to ferry in space, we should travel as quickly as possible. I believe that NTP is best “near-term” technology that could dramatically reduce travel times to Mars (this also helps out with the space radiation exposure). A hydrogen based system could even use LH2 to protect crew hab-module, further reducing radiation exposure.

    Highly Advanced Robotics: Because space is a very inhospitable environment we will need to rely upon robots and advanced intelligence agents for most of the exposed work. It is our brains that make the difference in space, our bodies become liabilities.

    Jon, thanks for bringing up this topic. It was challenging to develop a “prioritized” list of technologies that support the VSE. I hope that we will get a chance to use it in future pursuits.

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