The recent report from the National Research Council (NRC) Committee on Human Space Exploration has drawn a good deal of commentary from the space press. I’ve looked over the report and have my own thoughts, some quite orthogonal to most of the commentary so far. I find the report acceptable in some areas but woefully lacking in vision and imagination. Many standard assumptions and clichés about human spaceflight are taken for granted and very little thinking “outside the box” is evident. All in all, the report is a conventional, mediocre effort. But given how far strategic thinking about the U.S. space program has fallen, I am not surprised.
In common with virtually all current thinking on the space program, the report focuses on “exploration” as the principal activity to be undertaken by humans in space, defined by the committee as consisting of surface activities associated with various scientific investigations. Thus, at the outset, the entire human effort in space is oriented around activities that, from evidence of the last 30 years, are already known to be politically unsustainable over decadal timescales. That the adoption of this viewpoint was not inadvertent is shown by the complete absence of any consideration of the value of human spaceflight for operational and applications purposes, viz., the industrial development of space for a variety of critical national needs.
The history of human spaceflight since Apollo has focused on low Earth orbit – specifically, on the use of the Space Shuttle to conduct a variety of missions, including the assembly of the International Space Station. Many observers have criticized this era of spaceflight, especially in comparison with the great surface explorations of the latter Apollo missions. However, the past 30 years of space operations began as an attempt to make spaceflight “routine” by keeping costs down. The Shuttle was built because it was thought that reusability and high flight rates would make orbital flight cheap enough to enable a wide variety of activities in space. The Shuttle has an excellent operational record of 133 successful flights out of 135 attempts but as a spaceflight system, it never achieved the savings or flight rates initially projected.
The “policy failure” of the Shuttle (as it has been labeled by one observer) led to several decades of navel-gazing and pining for a more ambitious space program (with an oft-repeated call for new missions “beyond low Earth orbit,” the holy grail of space policy analysts). Fed largely by Saganism and Star Trek fantasies about “seeking out new life,” mission dreams focused primarily on humans to Mars. But whatever the proposed trans-LEO destination, the principal activities envisioned always consisted of “scientific exploration,” with the architecture always some derivative of the unsustainable Apollo template – a large mega-booster rocket, a throw-away spacecraft and a small Earth return vehicle.
Although the original idea and purpose of the Shuttle program was eminently logical, we had abandoned the systematic and incremental approach to space exploration during Apollo because of pressing geopolitical needs. The post-Apollo direction was an attempt to return to that step-wise template through the sequence of Shuttle, station and orbital transfer vehicle – back to a space-based transportation system that would ferry crew and cargo between LEO and destinations beyond, including geosynchronous orbit, the L-points, and lunar orbit and surface. By returning to these necessary and prescribed steps, and phasing them in over time (so as to be affordable), we would gradually move from a predominantly Earth-centric transportation system based around launch vehicles, to a space-based system built around elements that would remain permanently stationed in space for continuous availability and reuse. Such an extensible system would gradually expand the operational reach of humans into the space beyond LEO.
During the course of our thirty-year experience with Shuttle and Station, critical questions about the value of people in this region were answered in the affirmative. People working in space together with robotic assistants could build, repair and maintain large, distributed systems in space – facilities much larger than could ever be launched from the surface of Earth. The ISS is but one example. Future large distributed systems built on-site in GEO (or elsewhere in trans-LEO space) could become the communications and solar power complexes of the future. People and machines, working in these areas, could assemble the interplanetary spacecraft that have been the dreams of space advocates for years – giving us systems much more capable and less expensive than those launched from the surface of Earth, the deepest gravity well in the inner Solar System.
Even though these concepts are well understood, there is nothing about such possibilities in the new report – no mention of attempting this spaceflight template, one that would revolutionize space-based satellite assets, offer unprecedented bandwidth and coverage for global digital communications, afford us the ability to develop inexpensive and clean energy for a rapidly industrializing third world, and provide better security from both internal and external threats for the world as a whole – hardly small potatoes. All of these possible activities involve the need to prove vital engineering and science concepts that will inspire and propel the inevitable space-based economy that would follow.
Yet the new NRC report focuses exclusively on the old Apollo template – a human Mars mission, staged completely from Earth-launched assets (for a few crew members) to study a few scientific questions on a distant planet. Although such a program is far from worthless, it lacks the multi-dimensional appeal and the political attraction of a program that has lower buy-in costs (being incremental) and wider appeal (broad-based constituencies, diverse opportunities). Basically, it is the difference between a single-shot mission “stunt” and the creation of a long-term dynamic that moves humanity into space – the dynamic that gets us there. Once we possess the ability to get there, people will have the freedom to choose from an infinite spectrum of activities and rationales.
On their web site, the committee lists the formal presentations they received as well as the ~200 white papers individually submitted by interested parties. Within this mass of material is work (from several sources) explaining the substance and importance of a series of new and significant discoveries about the Moon’s polar regions. In the last 10 years, we have found that the Moon contains large quantities of water in the form of ice deposits. Water is an important substance with a wide variety of uses. It is even more valuable when it’s naturally available where we need it. One of the most important uses for water is as rocket propellant. In his presentation, Mike Duke carefully outlined the promise and remaining unknowns associated with accessing and using this off-planet resource. In addition, several contributed white papers pointed out how the rules of spaceflight could be fundamentally and favorably altered through the harvesting and use of lunar water.
None of these new, game-changing results are acknowledged in the report. The closest the report comes to evaluating the enormous leveraging potential provided by in situ space resources is the use of martian atmosphere to manufacture fuel for the return trip back to Earth. While certainly a worthwhile effort, it is inadequate. Completing a single human mission in the distant future does not compare in significance to creating an affordable, sustainable human space exploration program in the here-and-now. In contrast, the systematic extraction of water from the Moon would provide fuel and consumables for a variety of purposes in cislunar space, including the necessary and all-important ability to take space transportation from an Earth-dependent activity and transform it into a space-based operation, finally removing the necessity (and expense and limitations) of propellant being launched from Earth. A cislunar transportation system can take us to the planets – to Mars.
One may speculate on the reasons for this paucity of imagination in the NRC report, but I suspect it is because the current generation of scientists and engineers are hidebound by conventional thinking about space, as well as having an aversion to crossing those necessary bridges of technical readiness that lead to new capabilities. They believe that a space program consists of industry building big, complex machines that get launched, used and then thrown away – and a big government check gets cashed. Instead of a permanent human presence in space, their idea is to get there, do the mission and get home. It’s what they know – the proven model that worked for Apollo, the sleek white rocket pointing to infinity and the touchstone for large, exciting, spectacular space firsts. In contrast, the Space Shuttle – ugly and unloved – undertook pedestrian missions in low Earth orbit, circling close to Earth and completing unglamorous tasks like Hubble servicing or Space Station truss assembly – prosaic, but useful.
I plan to discuss other aspects of this report (some of which are quite good and insightful) in future posts, but my initial reaction to the report is one of disappointment in its missed opportunity. The authors had a chance to set out a logical rationale and a path for the implementation of long-term human presence in space. They had a capable staff and a wide variety of knowledge and interesting ideas to access in the years they’ve spent writing this report. Having served on previous committees like this, I understand the tendency to believe that you already have the expertise needed to evaluate the major program “covered” by your committee membership. I also know (and knew after my first experience) that such a feeling is invariably mistaken. The key facts and pieces of a logical space program can be found on the NRC Committee website – not in the main report, but in the materials presented and submitted to the committee by outsiders. However, like finding diamonds in the host kimberlite, one must ferret out and separate the gems from the gangue.