Friday, June 26, 2009
1. The current Constellation transportation architecture seeks to send 4 astronauts to the Moon's surface per mission. However, there is no requirement in the Vision for Exploration or Aldridge Commission documents for this number. Two astronauts would be enough to provide backup in case of injury. Including 4 astronauts instead of 2 per mission has the obvious benefit of larger crew, but it tends to drive up development cost, per-mission operations cost, and development risk. It also tends to reduce mass for equipment and engineering safety margins, and tends to extend development schedules. Increased development and mission costs reduce the funding available for other critical areas of the Vision for Space Exploration, such as technology development, innovation prizes, partnerships with commercial space, and robotic precursor missions to the Moon.
Why was a 4-astronaut mission requirement added?
Keeping in mind the goals of this committee to develop ISS transportation sooner, fit human space flight within the budget, investigate human spaceflight R&D and robotic precursor needs, and extend ISS beyond 2016, how would you adjust the transportation architecture if the per-mission requirement was relaxed to 2 astronauts?
2. One of the goals of the Human Space Flight Review Committee is to expedite a new U.S. capability to support use of the International Space Station. Keeping in mind the other goals of the Committee such as fitting within the current budget profile for NASA exploration, what are your suggestions for expediting such a capability? In other words, how would you bring such a capability online sooner than the current plan?
3. One of the goals of the Human Space Flight Review Committee is to stimulate commercial space flight capability. This is also a central and pervasive goal and exploration enabler in the Vision for Space Exploration and the Aldridge Commission recommendations. These documents also make it clear that by "commercial space flight", they don't mean large cost-plus aerospace contracts, but rather innovative entrepreneurs and businesses of all sizes that offer their space flight services to NASA *and* other markets. Keeping in mind the other goals of the Committee such as fitting within the current budget profile for NASA exploration, and thus recognizing the likelihood that any new funding would have to come out of existing human space flight programs, what are your suggestions for increasing NASA's encouragement for commercial space flight capabilities?
4. One of the goals of the Human Space Flight Review Committee is to fit NASA's exploration activities within the current budget profile. Do NASA's exploration activities fit within the budget outlined in the Administration's recent budget proposal, and if not, what are your suggestions for making these activities fit the budget? Do you see cost-saving opportunities in using commercial space flight services, using international participation, relaxing mission crew size requirements, relaxing schedule requirements, increasing research and development in low-cost approaches, or changing components of the transportation architecture?
5. Please see question #4. Could you answer those questions again, but this time assume that NASA's involvement in the ISS program is extended from 2016 to 2020?
6. One of the goals of the Human Space Flight Review Committee is to examine the appropriate amount of research and development activities needed to make human space flight more productive and affordable. The Vision for Space Exploration also emphasized research and development in a number of areas, such as in-situ space resource utilization, power systems, advanced computing, nanotechnology, biotechnology, optical communications, networking, robotics, materials, modular systems, pre-positioned propellants, advanced propulsion, and in-space assembly. The document "Launching Science: Science Opportunities Provided by NASA's Constellation System" also emphasizes a number of advanced technologies, such as aerocapture, nuclear electric propulsion, solar electric propulsion, and solar sails to support science, a central goal of the Vision for Space Exploration. The Aldridge Commission also recommended advanced technology development. In contrast, NASA has reduced its technology development efforts, canceled technology programs like New Millennium and NASA Institute for Advanced Concepts, failed to fund Centennial Challenges for several years, and broadly reduced research and development. Much of what remains in this area is directed specifically at the Constellation transportation system. Keeping in mind other goals of the Committee such as fitting human space flight efforts within the budget, what do you think is the appropriate amount of research and development activity to make human space flight more productive and affordable? What technologies would you invest in, and at what budget levels? How would you manage new technology development efforts (for example: grants? contracts? innovation prizes? DARPA model? emphasis on basic R&D, or technology demonstrations?)
7. One of the goals of the Human Space Flight Review Committee is to examine the appropriate amount of complementary robotic activities needed to make human space flight activities most productive and affordable over the long term. The Vision for Space Exploration also emphasized complementary robotic missions well beyond LRO:
"NASA will begin its lunar testbed program with a series of robotic missions. The first, an orbiter to confirm and map lunar resources in detail, will launch in 2008. A robotic landing will follow in 2009 to begin demonstrating capabilities for sustainable exploration of the solar system. Additional missions, potentially up to one a year, are planned to demonstrate new capabilities such as robotic networks, reusable planetary landing and launch systems, pre-positioned propellants, and resource extraction."
Keeping in mind other goals of the Committee such as fitting human space flight efforts within the budget, what do you think is the appropriate amount of complementary robotic activity? What are the highest priority missions for such robotic activity to prepare for and complement human exploration? How would you manage such robotic efforts (for example: use of commercial Google Lunar X PRIZE derivative services? Smaller but more missions typical of NASA Ames? Larger but fewer missions?)
8. One of the approaches emphasized by the Aldridge Commission to stimulate commercial space is the use of innovation prizes. Keeping in mind other goals of the Committee such as fitting human space flight efforts within the budget, would you increase the use of innovation prizes in a program like NASA Centennial Challenges to meet exploration goals? If so, what annual level of funding do you suggest for prizes? How many innovation prizes would you fund, and how large would they be? What innovations would be the subject of the prizes?
9. In many instances the use of space infrastructure, such as propellant depots, reusable space tugs, satellite servicing nodes, additional space stations, and other such systems has been suggested to assist with lunar exploration, and also to meet other government and commercial space needs. Keeping in mind other goals of the Committee such as fitting human space flight efforts within the budget, would you allocate NASA human space flight resources towards such space infrastructure, and if so, what types of space infrastructure? How would it fit in the exploration plans? For example, could a propellant depot help NASA achieve its goal of stimulating commercial space activity? Could it provide an on-ramp for international participation in the human exploration effort? Could it help NASA achieve its goal of developing a lunar transportation system?
10. Please consider all of the previous questions as an integrated whole. Also consider all of the objectives of this Committee as a whole. Does the current Constellation plan address the objectives of the Committee? Include all components: ISS gap reduction, reaching the Moon and beyond, fitting the budget, encouraging commercial space, extending ISS, and the optimal allocation, management, and focus of technology R&D and robotic missions. If the current Constellation plan doesn't address all of the objectives, how can we change the current plan to meet those objectives? If we cannot meet all of the objectives even with changes, how can we come closest, assuming the budget is not negotiable?
Tuesday, June 23, 2009
Constellation: Launching Science, or Leeching Science? Part 3: Constellation and Satellite Servicing
This third post in a series on Constellation and the National Research Council's document Launching Science: Science Opportunities Provided by NASA's Constellation System takes us back where we started at the beginning of Part 1 of the series: Satellite Servicing. A recent NASA RFI titled Feasibility of using Constellation Architecture for Servicing Existing and Future Observatory-Class Scientific Spacecraft (PDF) uses the NRC document as one of the main sources for examples of the types of satellites that would be the objects of servicing. In Part 1, we already looked at the types of science missions under consideration by the NRC document. Now, let's look at the types of satellite servicing that's described there.
Without going into a great deal of detail repeating the NRC report, here's a summary of some of its points:
- Although some level of satellite servicing is possible without special design considerations on the satellite to be serviced, designing for servicing helps a great deal. This includes grapple points, foot and hand holds, easy access to components to be replaced, safe fuels, and sharp points.
- Missions like Orbital Express and ESA's Automated Transfer Vehicle (ATV) demonstrate that cost-effective robotic satellite servicing is practical for many tasks.
- Designing for servicing may increase costs, but there are benefits to counter these costs, such as relaxed requirements for long lifespans of components that can be replaced.
- NASA has gained a lot of experience with satellite servicing.
As far as Constellation is concerned, the document concentrates on the satellite servicing potential of Orion:
"The Orion spacecraft, although capable of traveling beyond low Earth orbit, has a number of limitations with respect to acting as a servicing mission. Orion has limited capability for change in velocity (delta-v) and would require additional propulsion to leave low Earth orbit. The spacecraft is not equipped with an airlock, which would therefore require that the entire cabin be depressurized or that an airlock be provided for the crew. In addition, Orion has limited extra mass and volume capacity for carrying equipment for a servicing mission, such as a robotic manipulator system, toolkits, and any equipment to be installed. Any plan to use the Orion for a servicing mission will have to address these limitations. Options include launching a second spacecraft to carry servicing equipment, designing spacecraft to include many of the necessary tools and even an airlock, and launching a dedicated servicing spacecraft to which Orion would rendezvous and dock before journeying to the spacecraft to be serviced."
The document proposes using Orion (or robotics) and a servicing node at the Earth-Moon L1 or L2 point to allow servicing of various satellites planned for the Sun-Earth L2 point:
"Several of the mission concepts evaluated in this report would operate at the libration points a significant distance from Earth ... Although these sites are attractive for operating heliophysics and astronomy observatories, they are less than ideal for servicing purposes owing to their distance and communications lag times and for other reasons. One possibility is to move the spacecraft closer to Earth for servicing purposes and then move it back to its operating location. Several proposals exist for establishing a servicing node or way station at a closer location that could be visited either by humans in an Orion spacecraft or by a robotic servicing spacecraft. Transferring the observatory from one Lagrangian point to another requires very little change in velocity and subsequently only small amounts of fuel."
The document goes into more details about the potential servicing station at Earth-Moon L1 or L2:
"Such a servicing station would have a servicing node, which would remain in orbit and would require some additional avionics and propulsion capabilities beyond those found in a simple airlock. In addition to servicing spacecraft out at Earth-Moon L1, it could also possibly be used to aid lunar surface exploration. This servicing node could enable two types of robotic servicing: a robot operated by astronauts and a robot operated autonomously from Earth."
This type of servicing node could have other purposes, too:
"Ultimately, a servicing node at the Earth-Moon L1 or L2 point would make it possible to construct large astronomical observatories that surpass even Ares V single-launch capabilities ... It could also be used to facilitate lunar exploration goals, and in the far term, an Earth-Moon L2 point servicing mission could provide a stepping stone between lunar missions and Mars missions. It could be used as a test site for issues such as duration in space, distance from Earth, communication delays, and supply issues."
The document makes it fairly clear that by itself, Constellation is not very useful for satellite servicing. Perhaps, with a limited budget, robotic satellite servicing with modest capabilities focused on the most likely servicing needs, and no use of Constellation hardware, is the best route.
However, with budgets permitting, Constellation combined with other capabilities (such as a Centaur and a servicing node with an airlock) could provide significant science-enabling capabilities, and thus allow Constellation to deliver a lot towards one of its 3 main goals, science benefits, well before the lunar return. The question then becomes "will the science benefits be worth the cost"?
Satellite servicing clearly shows promise if it can be done in a cost-effective way. However, there are a number of potential pitfalls in using Constellation for satellite servicing beyond the obvious budget consideration. One pitfall is that a Constellation-based satellite servicing mission could lead NASA to simply engage in more in-house and cost-plus contract work with little benefit to the commercial space industry or U.S. economic health in general.
For example, the NRC document depicts a NASA concept for linking Orion with a servicing node that looks much like an ISS Node. The big question then immediately becomes "will this Node be a commercial system that helps to enable non-NASA business (for example, a Bigelow module, or some commercial LEO or GEO satellite servicing venture), or will it simply be another NASA cost-plus contract?" In other words, will it be a force-multiplier for the space economy, or will it absorb even more funds that could otherwise have been used as force-multipliers?
Another diagram in the NRC document shows a NASA concept where Orion is launched by Ares I and then docks with the Centaur and Servicing Node. Well, that's to be expected, since after all NASA is looking into the "feasibility of using Constellation architecture for servicing existing and future observatory-class scientific spacecraft". But there's more ... how are the Centaur and Servicing Node launched? Of course in the diagram they're launched by an unmanned Ares 1 rocket!
One of the central goals of the Vision for Space Exploration is economic benefits to the nation, in the context of expanding the commercial space industry, rather than just the cost-plus contractors. This was later emphasized by the Aldridge Commission. Even now, one of the 4 main objectives of the Human Spaceflight Commission is "stimulating commercial space flight capability". Encouraging commercial space has been a consistent focus in all of these policy directions that NASA has been given.
If we're to consider developing the expensive Constellation system for ISS and lunar crew transportation, and then operating that system for decades, all with very little benefit to commercial space, and if the Constellation components are also to be used in a satellite servicing system that will entail additional costs, if we're to gain any economic benefits from the whole effort, it's vital that the additional components used to enhance Orion's capabilities (eg: unmanned launch, servicing node) be commercial. Adding more cost-plus components to the satellite servicing architecture will only get us more deeply in the trouble that's already caused the need for a Human Spaceflight Review Commission.
On the other hand, if we do use commercial components that are also used for non-NASA business to enhance Constellation's capabilities into the satellite servicing arena, then Constellation will be that much closer to achieving at least 2 of the goals of the VSE: science and economic benefits. Constellation will be fulfilling at least part of its purpose.
Of course we could flip the partnership in the other direction, too. A COTS satellite servicing effort, perhaps building on COTS A-D efforts, for commercial satellite servicing capabilities could be offered. This would use commercial launch and a commercial human transport spacecraft to link with an Ares 1 launched cost-plus servicing node. Again, both NASA in-house/cost-plus contractor and commercial space would benefit.
This brings us back to the recent NASA RFI for satellite servicing ideas. Although the RFI does mention robotic and commercial servicing capabilities, it's clearly oriented towards the Constellation system. It would be preferable to look broadly at all satellite servicing options.
As a note, the original RFI mentioned a pre-RFI workshop around June 27, 2009. However, the workship has been postponed until sometime after June 27th (date TBD).
I have one final observation. The focus of the satellite servicing strategy outlined in the NRC document, and thus stressed by the NASA RFI, is on large heliophysics and astrophysics missions at L2. Are those the best candidates for satellite servicing? It seems to me that constellations of similar satellites are also good candidates for servicing. With such satellites, you can design the satellite servicing capabilities into multiple satellites with a single design, unlike the big single-case science missions. Then a single satellite servicing capability can operate multiple times on numerous satellites. There are many such satellite constellations, including some where the value of individual satellites is quite high. Many of these are not NASA satellites, though. Can NASA enable commercial space capabilities to be able to service these non-NASA satellites, and at the same time encourage the designers and operators of these satellite constellations to move towards serviceability?
Sunday, June 21, 2009
Thoughts on June 17 Human Space Flight Review Presentations - Part 2: Science, Security, and Economics
I'd like to discuss the central goals of the Vision for Space Exploration: economics, security, and science. The new Administration and the Human Spaceflight Review Commission may or may not focus on these VSE goals any more, but they still strike me as reasonable and useful ones as measures of exploration and human spaceflight benefits. Although in my previous post I contended that the Constellation presentation more or less ignored 3 of the 4 primary goals of the Human Spaceflight Commission, the same presentation actually does address all 3 of these central VSE goals. That is good, because it implies that they are engaged in finding ways to achieve these goals. However, I'm not convinced by the Constellation arguments in any of the 3 cases. I still think significant changes are needed to the current NASA Constellation plan to really achieve timely economic, science, and security benefits. There are many ways of doing that, though - some involving bringing in considerable commercial and international participation - but still leaving Constellation and its contractors with large and crucial exploration roles. Hopefully the Constellation position on Economics, Science, and Security will evolve in that sort of direction. At any rate, here's my critique of the recent presentation document:
Economics: The Constellation presentation has slides on the "Constellation Economic Impact". However, these slides merely show how taxpayer funds are sent to various geographical areas. Sending government money to various political districts is not the point of the economic benefit goal in the Vision for Space Exploration. This type of money distribution could be done with any government payments whatsoever. No space program is required for it. The VSE economic goal was to expand the commercial space economy, which means encouraging commercial space services that go beyond the NASA market. The Constellation program should figure out how it does this, or if it doesn't, how to change so it does it. Waiting 20 more years for the Moon base to be built to start a COTS-like lunar logistics program isn't by itself an attractive option, either.
Science: On one slide the Constellation presentation notes that Ares V can provide new capabilities for science. This is exactly the subject I'm addressing in another series of posts, and in fact the slide uses a quote from the document I'm reviewing. I'll just note that the authors of the document in question, although certainly wanting the science return that Ares V class science missions can return, are quite skeptical about the associated costs. Key considerations for Ares V science are opportunity costs in the form of unfunded science missions and technology development while Constellation is developed, the expected high cost of Ares V operations, and the difficulty in managing the cost of the types of large science missions that would use Ares V.
Security: The same slide mentions Ares V capabilities that could be used for Defense and Intelligence missions, such as an 8+ meter spy satellite in GEO to allow it to continually monitor an important location with sufficient resolution. Because of orbital mechanics constraints, LEO satellites are only able to observe particular locations on the Earth's surface every now and then. This GEO satellite with a huge mirror sounds like a great capability, and perhaps it is. However, it's worth noting that most, if not all, of the recent large defense and intelligence satellite programs have had extreme schedule delays, budget overruns, and similar problems. Can these agencies really afford Ares V launches, and, more to the point, the types of satellites that would use such capabilities? Note that many of these big security satellite programs have been canceled or had major restructuring events. How would such enormous satellites that would go on an Ares V fare in an era of "asymmetric warfare", where a cheap ASAT can take out a major satellite? How do they fit in with the current trends and needs for operationally responsive space? How do they fit with the recent Gates-driven budget changes that feature less "Transformational Space" and more "down-to-Earth" capabilities?
The bottom line is that having a NASA presentation about Ares V capabilities used for security purposes doesn't mean much. If NASA consults with its security counterpart agencies, and finds actual interest in such capabilities, then that's a different story altogether. The same goes for the argument, mentioned in the Aerospace Corporation presentation, about Constellation keeping the solid rocket industrial base strong for security reasons. Are any of the security agencies willing to back NASA by funding such Ares V class satellites (or at least serious investigations of them)? Are they willing to pitch in for the development of Ares V?
If either of these is the case, or if the security agencies show in some other ways that they are seriously interested in Ares V launches or other Constellation capabilities, then the Constellation program will have all at once considerably boosted its credibility. Until that happens, though, I'm going to classify Constellation's contribution to the central VSE goal of security as negligible.
I suspect that agencies concerned with national defense, intelligence, disaster preparedness and relief, homeland security, and the like would much rather that NASA:
- use lots of EELVs so they can share fixed EELV costs with NASA and maybe get some new launch pads
- encourage new commercial launchers so the security agencies eventually get lower-cost satellite launches which would help reduce the vicious circle of high launch costs driving high satellite costs and vice versa
- fly lots of robotic spacecraft missions so they can share satellite industry maintenance and development for their comsats, GPS satellites, and Earth monitoring satellites with NASA
- fly lots of commercial suborbital rocket missions to encourage this potentially useful type of asset for security and low cost space access purposes
- do lots of technology development in areas of interest to national security missions
- engage other nations in space cooperation without handing military technology to potential adversaries
This is just my impression. It seems to me that, if security is still one of the goals for human spaceflight, some effort on the part of NASA (as well as the independent Human Spaceflight Review Committee) should be made to find out what security agencies really need and can afford, and steer the Human Spaceflight plans in that direction to the extent that it's compatible with the other Human Spaceflight goals.
Saturday, June 20, 2009
Thoughts on June 17 Human Space Flight Review Presentations - Part 1: Addressing Committee Objectives
It's useful to remind ourselves of the "Scope and Charter" of the committee:
"Scope and Objectives: The Committee shall conduct an independent review of ongoing U.S. human space flight plans and programs, as well as alternatives, to ensure the Nation is pursuing the best trajectory for the future of human space flight – one that is safe, innovative, affordable, and sustainable. The Committee should aim to identify and characterize a range of options that spans the reasonable possibilities for continuation of U.S. human space flight activities beyond retirement of the Space Shuttle. The identification and characterization of these options should address the following objectives: a) expediting a new U.S. capability to support utilization of the International Space Station (ISS); b) supporting missions to the Moon and other destinations beyond low-Earth orbit (LEO); c) stimulating commercial space flight capability; and d) fitting within the current budget profile for NASA exploration activities.
In addition to the objectives described above, the review should examine the appropriate amount of research and development and complementary robotic activities needed to make human space flight activities most productive and affordable over the long term, as well as appropriate opportunities for international collaboration. It should also evaluate what capabilities would be enabled by each of the potential architectures considered. It should evaluate options for extending ISS operations beyond 2016."
The main objectives are faster support of the ISS (which I take to mean shrinking the ISS human spaceflight gap), going to the Moon and generally beyond LEO, stimulating commercial spaceflight (which I take to mean encouraging commercial spaceflight more than the status quo), and fitting the Administration's budget. Safety, robotic support, international participation, and long-term ISS use are also factors.
The main thing that struck me about the Constellation presentation is that it simply doesn't address the objectives. Follow this quick and to-the-point link; it captures my reaction exactly. Of the 4 main objectives, the only one it addressed head-on is "supporting missions to the Moon and other destinations". On the other issues, it didn't even attempt to present a solution. It didn't pass or fail - it got an incomplete.
On "expediting a new U.S. capability to support utilization of the International Space Station (ISS)", the Constellation presentation was silent. It mentioned having ISS crew transport by 2015, the current goal, and how they'd made changes to improve confidence they'd meet that date (eg: reducing initial crew size to 4 on ISS missions). However, "expedite" doesn't mean "increase confidence you'll make the current late date". It means "accelerate the process or progress of : speed up". The presentation doesn't suggest any ways to have Ares/Orion ready for ISS transport by, say, 2013, nor does it suggest any ways to have any other U.S. system ready by that time.
Even former NASA Administrator Griffin always claimed that Ares/Orion was only meant as a backup for ISS support, and commercial transportation services were the intended route. Thus the natural inclination should be for NASA management to encourage commercial services to take on that role. The Constellation presentation could have suggested a COTS-D or similar competition for human transportation services, or some other means to get commercial vendors working on basic ISS transportation. Then Constellation could concentrate on the Moon and Beyond. Alternately, the presentation could have suggested ways to alter Ares/Orion to be ready by 2013. It did neither.
On "stimulating commercial space flight capability", again the Constellation presentation was silent. It has a line about "promoting international and commercial participation in exploration", but no details on what that participation is. Where is this participation in the plan? The original goal of the Vision for Space Exploration was for launch support to be done commercially, except perhaps for heavy lift, if needed. Where is that in the plan? The presentation didn't suggest that any of the components of the Constellation architecture be implemented commercially. There's a picture on "Future Exploration Capabilities" with an Ares V linked to some "Commercial and Civil LEO" spacecraft, but what commercial activity is going to be launched by Ares V? There's a slide on "Economic Impact: Contractor" and others on billions of dollars of prime contract value (as if high cost is a virtue), but that's not commercial, it's government contracts. If a contractor is going to sell commercial services enabled by its government contracts, I'm willing to call that commercial, but how much of this Constellation contract work fits that description?
One gets the impression that commercial services are left for some distant future generation, after Constellation has become operational and the NASA base is constructed. Then, if the future NASA is so inclined, there might be some room for a little commercial supply to give NASA some room to work towards Mars.
Finally, on "fitting within the current budget profile for NASA exploration activities", the Constellation presentation is once again silent. There are notes about how "development and operations costs must be minimized", how life cycle costs are reduced, and so on, but the point isn't whether or not Constellation is straining really hard to reduce costs. The key question is: Does Constellation fit within the current budget profile? The budget profile is what it is. If, as former NASA Administrator Griffin has suggested, Constellation doesn't fit within the current budget profile for NASA exploration activities, Constellation needs to change to fit, or be replaced. Either show that you fit the profile, or what changes will allow you to fit the profile. The Constellation presentation didn't do that.
Fitting the current budget profile is a key point. All sorts of trends suggest that the budget will continue to be difficult for NASA exploration in the years ahead, just as was often noted by many commentators starting in 2005. Note the wider political, budget, and demographic trends. Note the charter of the Human Spaceflight Review Committee, which opens up a real possibility of shifting exploration resources from Constellation proper to ISS support after 2016, expediting ISS support (shrinking the gap), and R&D plus robotic exploration activities that complement astronaut exploration. There's a lot of justification for these potential budget shifts, so it's important for the astronaut transport plan to fit within a budget that allows a sufficient amount of such actitivies. Fitting the current budget profile is just a start in that direction.
In contrast to the Constellation presentation, the EELV presentation addresses the central HSR key objectives head on, showing how it can fit the budget, expedite ISS support, implement Moon missions, and work commercially. It would be interesting to see if the ULA is willing to put "skin in the game" and also to not get funding until milestones are reached, similar to the COTS A-C arrangement.
Thursday, June 18, 2009
Constellation: Launching Science, or Leeching Science? Part 2: Constellation and Technology Development
Assessing the value of lowering science mission costs by avoiding technology development clearly has to be done on a case by case basis. Many factors come into play. What is the cost of the heavy lift vehicle, in terms of development and operations? What is the cost of the specific technology development? Can this cost be accurately estimated before the technology is developed? How much mission cost does the technology, if developed, save? Is the technology applicable to one special science mission, or is it relevant to many science missions, or perhaps even other missions, both commercial and government?
The report cites examples where Ares V capabilities can replace a new technology altogether for some missions:
"For Generation-X, the Ares V would eliminate the need for multiple launches, complex packaging, and on-orbit assembly."
A number of questions arise. From a policy standpoint, do we want to eliminate the need for multiple launches, if those launches are done by vehicles that already exist and are under-used? Would multiple launches be beneficial from the standpoint of sharing fixed launcher costs with other missions - missions that perhaps are critical to national security, the commercial space economy, or monitoring the Earth's environment? Likewise, do we want to avoid on-orbit assembly, or is this a capability that is in the national interest to develop more fully? In essence, is the science mission to be evaluated simply on its science merits, or by other considerations as well? Finally, strictly from a science mission benefit perspective, how does the cost savings of avoiding multiple launches, complex packaging, and on-orbit assembly compare to the cost of using Ares V?
"The reliance on technologies such as aerocapture, nuclear electric propulsion, solar electric propulsion, or solar sails can potentially be eliminated from missions such as the Solar Polar Imager, Interstellar Probe, Titan Explorer, and Neptune Orbiter with Probes."
Do we really want to avoid developing technologies like aerocapture, nuclear electric propulsion, solar electric propulsion, or solar sails? These technologies can be applicable to many missions. Can we support a technology development effort, and perhaps a technology demonstration effort like the recently cancelled New Millenium program, so the first science mission in line for a technology doesn't have to pay for it? If we back up a second, we might ask ourselves which technology we want to develop: heavy lift, or technologies like aerocapture, solar sails, and others? What will the technology development cost? Will developing solar sails and aerocapture cost as much as heavy lift? Once developed, will solar sails and aerocapture cost as much as heavy lift to operate, or will these technologies tend to decrease operations costs (or increase science capabilities for a given dollar amount)? Similar thoughts seem to have crossed the minds of the committee members:
"... the committee noted that several technologies were required for multiple mission concepts and were essentially “mission enabling,” meaning that the mission could not be accomplished without them. These include propulsion technologies that might allow an alternative to the use of a heavy-lift launch vehicle such as the Ares V and are applicable to multiple missions (for example, aerocapture, which can be used at Venus, Mars, Titan, and Neptune; and solar sails, which can be used for the Solar Polar Imager and Interstellar Probe missions). If NASA develops these technologies, an Ares V launch vehicle might not be required for these missions but might enhance them."
Of course given the choice, the committee will take the technology development AND the heavy lift! It's not clear that they'd choose heavy lift if they had to choose between the 2, though.
Note that even the massive Ares V heavy lift capability is not necessarily enough to allow science missions to avoid technology development. From the report:
"Of the mission concepts that the committee considered, the Interstellar Probe, Neptune Orbiter with Probes, Solar Polar Imager, and Titan Explorer could all directly benefit from some form of in-space propulsion technology even if the Ares V is available."
The committee notes that NASA technology development isn't what it used to be. I'm sure the members realize where those technology development dollars went:
"In the recent past, NASA undertook a number of impressive in-space propulsion technology development projects that reached moderate to high technology readiness levels and demonstrated significant promise for future missions. However, for various reasons the agency has eliminated much of this research. The committee concluded that at least some of these technologies will be required for future missions even if they use the capabilities of the Constellation System.
Finding: Advanced in-space propulsion technology may be required for some science missions considered for using the Constellation System."
But how can we afford advanced propulsion system development when we need to fund Ares 1, Ares V, Orion, and so on?
Advance propulsion isn't the only technology that isn't being developed:
"The committee requested and received information from NASA about the planned course of evolution of the Deep Space Network. It learned that by 2025 the DSN may not reliably meet the current and projected uplink and downlink requirements. These current and projected requirements do not include any of the Constellation-enabled missions reviewed during this study, which nominally would fly in the 2020-2035 time interval. NASA is concerned with the deterioration of the existing infrastructure, particularly the 70-m antennas now more than 40 years old, and the lack of overall investment to modernize the DSN to accommodate the expected increase in data rates from a variety of missions, including missions to the Moon and Mars. Absent such modernization, the data return from the Constellation-enabled missions might be compromised and fail to fulfill the potential of these very expensive missions.
Finding: Science missions enabled by the Constellation System will increase the strain on the capabilities of the Deep Space Network."
The whole theory of using Ares V to enable highly-capable science missions is starting to sound worse and worse. The launcher will be expensive, the missions will be expensive, advanced propulsion has been dropped, and we won't have appropriate DSN capabilities for such missions. One gets the impression that we should be working on advanced propulsion and other technologies, as well as the DSN, before considering heavy lift. In fact, the original Vision for Space Exploration was intended to invest heavily in advanced technologies of many kinds.
In the case studies I'm covering, the committee was concerned with ambitious robotic science missions, but one has to wonder how such technology development (advanced propulsion, advanced communication, aerocapture) and operations (multiple launchers, space assembly) could also be used in astronaut exploration missions?
Tuesday, June 16, 2009
- Science Enabled by Heavy Lift
- Constellation and Technology Development
- Constellation and Satellite Servicing
The early sections of this document describe a number of science mission concepts that could use Constellation. In several of cases, it was found that Constellation would not help the mission, so those missions were dropped from the study. Other missions were helped somewhat, but not enough to warrent further study. The report focused on a select group of missions that have high science potential and that would be enabled or considerably enhanced by use of Constellation hardware. In most cases the Constellation hardware in question was Ares V; Ares 1 was found to have similar capabilities to existing rockets for science purposes. Two missions, "Exploration of Near Earth Objects via the Crew Exploration Vehicle" and "Dark Ages Lunar Interferometer", used other Constellation hardware, but these strike me as being more about the human exploration and lunar surface development efforts of the main Constellation effort. I'll skip those and concentrate on the majority of the report's missions, which are traditional robotic science missions enabled or enhanced by Ares V.
Here are some important quotes from the report:
"Finding: The scientific missions reviewed by the committee as appropriate for launch on an Ares V vehicle fall, with few exceptions, into the “flagship” class of missions. The preliminary cost estimates, based on mission concepts that at this time are not very detailed, indicate that the costs of many of the missions analyzed will be above $5 billion (in current dollars). The Ares V costs are not included in these estimates."
"... expensive space science programs will place a great strain on the space science budget ..."
Given the long duration and high expense of the Constellation development phase, the high expense of the subsequent lunar surface missions, and the potential for cost overruns in these big programs, it's a pretty fair assumption that space science budgets will continue to be under strain. Given the problems with some of the NASA Science missions, in particular its larger and more expensive missions like the Mars Surface Lander, James Webb Space Telescope, and others, the space science area is likely to be under additional strains from within. Unfortunately, this is not a physics case study where internal and external pressures balance harmoniously; this is a an over-full balloon run over by a steamroller.
Given these circumstances, how is the NASA Science community going to afford missions that, in current dollars, would likely cost over $5B in initial estimates, would likely have cost overruns and delays, and would also have to pay for the use of the expensive Ares V heavy lift vehicle?
When answering that, consider the current and probable future size of the NASA Science budget, the cost of the missions in question, and the fact that NASA Science is divided into separate areas with their own funding blocks: Astrophysics, Earth Science, Planetary Science, and Heliophysics.
"The committee notes that the combined effect of expensive payloads and expensive launchers would distort the balance of the space science program."
When your balance is distorted, you fall on your face. This is why the food pyramid, with numerous small missions (smallsats, suborbital missions, and the like) providing a solid foundation, a few typical medium-sized missions filling in the center, and the occasional large flagship mission over $1B pushing the envelope is a more balanced and stable shape.
"With the advent of the Ares V, the challenge for program managers will be to temper the appetites of scientists who will clearly recognize the dramatic scientific benefits enabled by the launch system. There will need to be an enforced paradigm shift where cost, rather than launch system capability, is the design limiter."
In other words, maybe we can manage science missions to be low-cost in spite of the larger mass of the missions. This sounds like wishful thinking to me. Look at what already happens with large NASA, NOAA, and DOD missions - one after another after another after another. They don't take advantage of extra mass by making the mission cost less; they cram every capability they can in every last kg. Look at the lessons of Apollo, or Titan. The committee is aware of this:
"Prior spaceflight experience demonstrates that payloads fill all available weight and volume budgets (and power and telemetry budgets as well)."
It's not likely that virtuous program managers will restrict their spacecraft to low cost use of Ares V mass capabilities by, for example, just using the mass for lots of fuel, and otherwise getting by with the instruments and capabilities of a $400M mission. There are too many other pressures - political, science, career, management, and so on. It's not impossible, but I wouldn't risk the next few decades of NASA science on the possibility that we will manage NASA Science in such a way that Ares V class science missions are cheap.
The report also relates a "Cautionary Tale" of the Voyager-Mars robotic science mission that was planned for the Saturn V as part of the Apollo Applications Program, but was cancelled.
"During the course of this study, no Earth science mission concepts were proposed to the committee. A proposed NASA workshop on the Constellation System and Earth science was canceled due to lack of interest, and only the most basic ideas about using Constellation for Earth science were discussed at the Ares V Solar System Science Workshop."
I'm not against heavy lift per se, but the current NASA heavy lift plan is incredibly expensive. It's the development and operations expense, and the corresponding missed opportunities, that concern me.
If there was a legitimate market for heavy lift, it could be worth the effort to make it happen, perhaps on a more affordable and less grandiose scale than Ares V, with a scaled-up COTS-like commercially-oriented effort.
Alternately, if there was a real government need for heavy lift, it might also be worth pursuing. A cookie-cutter series of similar nationally-important satellite missions that need Ares V payload capabilities, but that don't break the bank (eg: because of shared spacecraft development costs) would make Constellation a whole lot more attractive. NOAA, DOD, and intelligence communities all have nationally-important lines of multiple similiar satellites, so this scenario isn't impossible, but it hasn't happened, and in fact these agencies seem, if anything, to be in dire need of smaller, more responsive, and more agile spacecraft and launchers.
As it stands now, heavy lift doesn't appear to be a priority. Even for ambitious missions, other approaches that use smaller launchers and capabilities like refueling and spacecraft assembly appear more useful.
Yet heavy lift is so tempting because it gets rid of the need for various new technologies, doesn't it? That's a subject for a future post in Part 2: Constellation and Technology Development.
Saturday, June 13, 2009
Griffin: “This review is not, in my judgment, necessary from a technical point of view”
A lot of people would argue with that, but I won’t because it’s almost besides the point. The inescapable problems with NASA’s current Ares-based approach aren’t technical. They’re about budgets, policy, politics, goals, stakeholders, opportunity costs, management, schedules, risks, national relevance, return on taxpayer investment, and priorities.
“Griffin said he doesn’t think the administration’s review will mean any major changes for Constellation”
He’s flat-out wrong if the review panel does its job.
Here are the main goals of the panel:
“a) expediting a new U.S. capability to support utilization of the International Space Station (ISS);”
This means the goal is to speed up ISS support, presumably because the current plan isn’t satisfactory. We already know from Griffin himself that we can’t appreciably speed up ISS support with Ares 1/Orion. Whether the committee’s recommendation for solving this one replaces or stands next to Ares/Orion, it’s certainly a major change to the current Constellation plan.
“b) supporting missions to the Moon and other destinations beyond low-Earth orbit (LEO);”
There’s not necessarily a change here from the status quo, barring things like technical showstoppers in the Ares plan.
“c) stimulating commercial space flight capability;”
The Constellation plan does this a little bit with the COTS A-C ISS cargo effort, but I doubt the Administration would make stimulating commercial space flight one of the major points if they were satisfied with that. Now there are many ways NASA could stimulate commercial space flight capability with its human spaceflight program: COTS-D or similar ISS efforts, replacing Ares 1 with EELVs, sticking orbital propellant depots into the lunar architecture, using commercial lunar robotics, using Bigelow stations or DragonLabs for HSF science and engineering, using crewed reusable suborbital vehicles for various purposes, etc … these don’t all represent changes to the Ares-based hardware architecture, but they’re all major changes to Constellation.
“and d) fitting within the current budget profile for NASA exploration activities”
Based on estimates of Constellation costs such as the one by the CBO, and based on the actual numbers in the current budget profile, it looks like this one alone will force major changes to Constellation, which is a budget-buster. Again, the change might not be replacing Ares. Maybe it will have to do with schedules, or international partners, or things like that. Whatever it is, though, if the Committee actually addresses the point, it’s bound to be a major change to the current Constallation plan.
“The space agency had its change you can believe in”
Well, yes, that was the Vision for Space Exploration. Then in 2005 the space agency had another change that’s a lot harder to believe in. You can see some examples of how different Griffin’s Constellation is from the Vision for Space Exploration at this post:
Until we fix or remove Constellation, we’re stuck with, as a recent Space News editorial title put it: “Constellation vs. Everything Else”.
Thursday, June 11, 2009
Shelby holds up NASA funding; Bigelow's response to Shelby - RLV News
Wednesday, June 10, 2009
Build-up space-faring infrastructure
Robotic precursors lead the way
NASA relationship to the private sector must be decisively transformed to implement the new Vision
NASA and the private sector - Some specifics from the Aldridge Commission Report
NASA should contract for services where possible (e.g., LEO access)
Independent technical, cost and innovation oversight
Use contracting authority and other incentives to nurture reinvigorated space industry
Seek international participation and investment in VSE
What is NASA Doing Wrong?
No robotic exploration after LRO (Ed. note: This has changed, but not nearly enough.)
Ares launch system
- All the disadvantages of Shuttle-derived with none of the benefits
Agency still unclear about "mission" on the Moon
- List of reasons to go to Moon are unfocused and peripheral; a catalog, not a rationale
Creating a space-faring infrastructure
Reusable and serviceable systems in cislunar space and planetary surfaces
Extracting useful products from planetary materials
Handling and using cryogenic fluids in microgravity and on the Moon
Transportation architectures and nodes in cislunar space
Comm, navigation and data systems; extend GPS to cislunar space
If I were king…
CEV: Develop launch system alternatives
- Shuttle-C, EELV, new commercial
- Orbiters, soft-landers, rovers to survey and prospect
- Engineering tech demos for ISRU, habitat placement, site preparation
- Infrastructure emplacement: landing pads, roads, hab sites, power and thermal control systems
Use private sector to augment capabilities for both of above
- Per Aldridge Commission recommendations; greatly expand data purchase, LEO access contracts, prizes
- Need to re-build aerospace industrial base
Sustainability: An Alternate Concept
True Shuttle-derived + commercial
- 2 Shuttle-C side-mount launches to L1 staging node
- CEV adaptable for Shuttle-C, EELV, or commercial LV
- ISS used for technology research, demos (e.g., experimentation with cryogenic liquids in microgravity)
Early and continuing robotic presence
- Use robotic missions to establish presence on Moon, characterizeresources, demonstrate processing
- Multiple and continuing series of robotic missions maintains program momentum, new discoveries, prep for humans
- Develop large cryo-based lander (lunar "Progress");2 mT delivered to lunar surface
- Prepare outpost site for human arrival
Pace program to available resources
- We’ve survived previous "human spaceflight gaps"
- If major goal is to revitalize aerospace industry, must create incentives for them to investIR&D in program (e.g., tax breaks, prizes)
Primarily, this is NOT about money
- It’s about understanding your "mission"and a determination to do it cleverly, despite obstacles
Tuesday, June 09, 2009
"Not One Thin Dime"
"Apollo on Steroids"
"If you are looking under the hood, then you are calling me a liar."
"All we need is a good map."
"Will unproven cargo capabilities close the manned spaceflight gap faster than the work NASA has done on Ares and Orion?”
"Let me remind you that NASA is not the department of education."
Monday, June 08, 2009
"The fundamental goal of this vision is to advance U.S. scientific, security, and economic interests through a robust space exploration program."
"the United States will:
- Implement a sustained and affordable human and robotic program to explore the solar system and beyond;
- Extend human presence across the solar system, starting with a human return to the Moon by the year 2020, in preparation for human exploration of Mars and other destinations;
- Develop the innovative technologies, knowledge, and infrastructures both to explore and to support decisions about the destinations for human exploration; and
- Promote international and commercial participation in exploration to further U.S. scientific, security, and economic interests."
"Develop and demonstrate power generation, propulsion, life support, and other key capabilities required to support more distant, more capable, and/or longer duration human and robotic exploration of Mars and other destinations"
"Pursue commercial opportunities for providing transportation and other services supporting the International Space Station and exploration missions beyond low Earth orbit."
"Acquire crew transportation to and from the International Space Station, as required, after the Space Shuttle is retired from service"
"NASA will begin its lunar testbed program with a series of robotic missions. The first, an orbiter to confirm and map lunar resources in detail, will launch in 2008. A robotic landing will follow in 2009 to begin demonstrating capabilities for sustainable exploration of the solar system. Additional missions, potentially up to one a year, are planned to demonstrate new capabilities such as robotic networks, reusable planetary landing and launch systems, pre-positioned propellants, and resource extraction."
"Use lunar exploration activities to further science, and to develop and test new approaches, technologies, and systems, including use of lunar and other space resources, to support sustained human space exploration to Mars and other destinations"
"NASA does not plan to develop new launch vehicle capabilities except where critical NASA needs—such as heavy lift—are not met by commercial or military systems. Depending on future human mission designs, NASA could decide to develop or acquire a heavy lift vehicle later this decade."
"In the days of the Apollo program, human exploration systems employed expendable, single-use vehicles requiring large ground crews and careful monitoring. For future, sustainable exploration programs, NASA requires cost-effective vehicles that may be reused, have systems that could be applied to more than one destination, and are highly reliable and need only small ground crews. NASA plans to invest in a number of new approaches to exploration, such as robotic networks, modular systems, pre-positioned propellants, advanced power and propulsion, and in-space assembly, that could enable these kinds of vehicles. … Other breakthrough technologies, such as nuclear power and propulsion, optical communications, and potential use of space resources, will be demonstrated as part of robotic exploration missions. The challenges of designing these systems will accelerate the development of fundamental technologies that are critical not only to NASA, but also to the Nation’s economic and national security."
"Many of the technical challenges that NASA will face in the coming years will require innovative solutions. ... One way that NASA plans to do this is through a series of Centennial Challenges. ... NASA plans to establish prizes for specific accomplishments that advance solar system exploration and other NASA goals."
"The space missions in this plan require advanced systems and capabilities that will accelerate the development of many critical technologies, including power, computing, nanotechnology, biotechnology, communications, networking, robotics, and materials. These technologies underpin and advance the U.S. economy and help ensure national security. NASA plans to work with other government agencies and the private sector to develop space systems that can address national and commercial needs."