Blech, sorry about the delay but I've been caught in the dread forces of engineering homeworksplosion. But now I am here, and thus, now it is once again that time. Last week, we left off with President Bush's proposal of what Administrator Harrison Schmitt dubbed, "Project Constellation." This week, let's talk about Constellation in a little bit more detail, shall we? 1263 replies, 156559 views
Eyes Turned Skyward, Part 2: Post #29
During the course of their analysis, the Office of Exploration concluded that all existing human exploration plans, including previous NASA plans, could be sorted into five basic categories: Lunar Sorties, Lunar Bases, Mars Sorties, Lunar Sorties and Mars Sorties, and Lunar Bases and Mars Sorties. While many plans also included additional development steps, such as the construction of Lunar colonies or Martian bases, these steps were generally envisioned either as follow-ons to a core program that fit into one of the previous categories, or as support mechanisms to a categorizable program. To determine which of the five possible approaches was best, they stringently analyzed all of them under conditions passed down from the Administration and from the NASA Administrator, particularly an assumption of (inflation-adjusted) flat budgets for the foreseeable future, constructing reference and alternative scenarios for each one based on both the best previous NASA studies and the multitude of private studies that had flooded their mailbox. The resulting Report of the National Aeronautics and Space Administration's Office of Exploration on the President's Space Initiative, a title quickly condensed to "Exploration Report", weighed in at over 500 pages of detailed technical and financial analysis of a wide range of mission options, even if the resulting recommendations were surprisingly simple and conventional.
During its analysis, the Office of Exploration was forced to discard the three options involving Mars flights as non-viable. While exploring Mars was highly exciting and a truly pioneering possible goal for NASA, even aggressive deployment of the best new technologies suggested to the Office of Exploration could not get humans there fast enough, safely enough, nor cheaply enough for Mars exploration to be viable. Spending a decade or more with the only NASA program being Freedom could lead to severe technical and workforce difficulties, especially if the new technologies, mostly in an early stage of development as of 1989, proved less useful than believed or even impossible to implement. Even at that, the assumed funding profile of NASA in future years could not support Mars exploration, Freedom, a diverse and capable robotic exploration program, and NASA's other research areas at the same time. Something would have to give, and the Office believed it would most likely be the ambitious, expensive, and as yet unproven Mars exploration program. Thus, while the next century might indeed see a journey into tomorrow, it would of necessity have to be tomorrow's journey. At most, an R&D program might be created to investigate advanced technologies which could either lower costs or accelerate the timeframe of piloted Mars missions, something recommended by the Office in all of its reference approaches. Those options involving lunar exploration before Mars exploration were even worse from the standpoint of budgets and schedules. Under the budgetary and technological assumptions of the report, a Mars mission might not be possible before the 2020s or even the 2030s, a time horizon so far ahead that any planning, even the vaguest and most general, was an absurdity, almost certain to be overtaken by unforeseen events.
Unlike Mars missions, however, lunar missions were tagged by the report as entirely possible, even under the stringent budget conditions imposed by the Administration. Much of NASA's hardware was, after all, derived from the equipment used for the first lunar missions, and the Moon posed far smaller technical challenges for just surviving to reach it than Mars did. The only question remaining was whether a program of lunar sorties alone or lunar sorties followed by a lunar base was the better choice. Limited to briefly and superficially analyzing a few sites scattered across a vast amount of land, sorties seemed to offer little promise of in-depth scientific exploration of the Moon, and no hope of developing the tools and technologies needed to exploit lunar resources for future missions. By leaving little infrastructure in place, later missions would be no cheaper or better supported than early ones, increasing the risk of the entire program ending like Apollo, with an expensive and capable system designed and implemented only to be dismantled almost immediately as it started to demonstrate itself. All in all, sorties alone could only offer cost advantages, and that only if a strictly limited number were planned. Therefore, the report recommended that the Administration and Congress adopt Option B, Lunar Bases, together with a relatively small advanced technology program intended to "pave the way" for Mars and a number of other more minor research and development or support programs to extend the capabilities of future lunar or Mars missions beyond the state of the art. To complement this recommendation, the Office of Exploration condensed what it considered some of the best proposals that had been developed, either by NASA or by other organizations, into a single reference architecture for the entire Constellation program. While several alternatives, including Office-constructed reference architectures for the other four mission options, were presented, the final report made it clear that Option B, in the design presented by the Office of Exploration, was their preferred architecture choice.
In the reference implementation of Option B, Project Constellation would start with the completion of Freedom in 1992, leading to a diversion of Freedom development and construction funds towards the existing Advanced Crew Vehicle program, a new lunar lander, upgrades to the Saturn Multibody (primarily involving the use of weight-saving materials such as new aluminum-lithium alloys in vehicle construction), and a series of lunar precursor missions, possibly involving international partners. Before the ACV and lander finished development, orbiters, landers, and possibly even sample return probes would venture to the Moon to fill in the gaps left by the Lunar Reconnaissance Pioneer, narrowing down the list of sites to visit and providing an initial view of the Moon. Once the ACV and lander were completed and tested, estimated to be by 1998 or 1999, the first lunar mission would be launched. Using multiple Saturn Heavy launches, an ACV/lander/Earth Departure Stage stack would be assembled in low Earth orbit, then depart for the Moon. Once near the Moon, all four crew members would enter the lander and depart for the lunar surface, where they would spend up to two weeks (if a second cargo lander had been dispatched on a previous launch) exploring the lunar surface.
After a series of these sorties, perhaps five or six in total, the ideal location for a permanent base would have been determined. Before any further human crews ventured there, a series of cargo landers would transport essential equipment, such as habitat modules, power generation systems, and other key elements of any base to the chosen location, where teleoperated construction equipment also transported by the cargo craft would begin assembling and checking out the base. The first human crew would continue these assembly and checkout activities, focusing on those areas where a human presence, not merely a human operator, were needed for effective operation. This crew would stay at the base for 180 days, like their colleagues on Freedom, transforming the base from a jumble of modules and landers into a tiny "home away from home" on the harsh lunar surface. After the astronauts returned from their lunar mission, another crew might arrive and continue the work of exploring the area around the base and demonstrating key technologies and capabilities needed for future lunar bases and Mars exploration, or the base equipment might be teleoperated for some time between crews. With the lunar base constructed and beginning to operate, if only in a human-tended mode, many options presented themselves. An infrastructure of fuel depots, reusable space tugs (both electric and chemical, using aerobraking to ease the return from cislunar space), reusable landers, perhaps even that chimeric dream of a reusable launch vehicle might be used to reduce operational costs and allow more frequent ventures to the base, or the base's expansion. If initial experiments in in-situ resource utilization, in extracting oxygen from lunar rocks for example, had panned out, the base could be enlarged to house even more people, supporting a growing production of lunar resources. Alternately, the base could be only intermittently crewed as part of Mars simulations, focusing on making the jump to the next possible destination beyond Earth. Any of these options, or more, could be selected by a future Congress and President, since visionary leadership on the part of the current Congress and President would have enabled them to make that decision. However, they were not part of the core program, and not needed for the United States to reestablish its leadership in space exploration.
The entire recommended program was estimated by the Office of Exploration to cost approximately $50 billion; $12 billion for development of all the spacecraft needed for the lunar landings, plus another $8 billion for the recommended six mission sortie sequence, plus $10 billion for Mars-related R&D and a suite of precursor missions to Mars, leading up to the Mars Sample Return widely agreed to be necessary before any human missions to the Red Planet, and finally $20 billion for construction and several years of operation of the planned lunar base[1]. These $50 billion in expenditures would be spread across twenty years of development and operations, leading to an average annual cost of $2.5 billion, only about 25% larger than the projected ongoing cost of maintaining and operating Freedom. Of course, the peak funding requirements would be higher, but given the administration’s official budget estimates these would be easily manageable, little worse than having to support Freedom’s development while Spacelab remained operational.
Not unjustly, the Lunar Society saw the recommendations of the Exploration Report as a significant victory for its vision of space. For more than a decade, it had been vigorously supporting a return to the Moon and the construction of a lunar base as the best next steps for NASA beyond Earth orbit. While it had turned towards supporting private industry as the spearhead of further development and private efforts to lower the cost of launch during the 1980s, enough of its members still held the agency that had landed fourteen men on the Moon in sufficiently high regard that they were willing to go along with a plan that seemed to herald a new age for lunar exploration and development. Similarly, the National Space Organization was, if not as enthusiastic about the report, then at least willing to go along with it, happy that NASA, and apparently the administration, were focusing again on space exploration. If Carl Sagan had still been at the helm, he might have pushed for greater integration of robotic exploration and international collaboration, but he had stepped down from the leadership years earlier to pursue his interests in science advocacy and skepticism outside of the NSO.
In the halls of Congress, meanwhile the Exploration Report was meeting a more ambivalent treatment. Although the time was simply ripe for beginning a major new space initiative designed to reinvigorate NASA from the relative torpor it had languished in for the past two decades, even with the growing deficit, or perhaps because of it, the $50 billion price tag (even spread out over twenty years) seemed overly high, and committing future Congresses to take specific action such as setting up lunar bases a step too far. The lower cost Option A, lunar sorties together with studies of lunar bases and Mars missions, and a Mars precursor program, was more attractive to a Congress and Administration looking to tackle budget deficits, offering most of the political advantages of a reinvigorated space program at considerably less cost. It would still allow a variety of new contracts to flow into aerospace companies hurting from the end of the Cold War, and still allow Congress members to point and say, “Yes, the United States can Do Great Things,” but without breaking the bank. This revised proposal was able to easily pass through the House and Senate, allowing Constellation to pass from proposal to policy by late 1990.
[1]: This is similar generally to the expected costs of a number of proposed lunar return and base construction studies IOTL during the 1980s and 1990s. Obviously in Eyes Turned Skywards they benefit particularly from not needing to develop a new heavy-lift launch vehicle, something which was often one of the major costs IOTL.
