By Robert Zubrin. Dr. Robert Zubrin, an aerospace engineer, is president of the Mars Society (www.marssociety.org) and author of "The Case for Mars: The Plan to Settle the Red Planet and Why We Must". A translation in French of this article has been published in LE TEMPS dated Feb 19th 2010 . On February 2, 2010, the Obama administration announced a new space policy, incorporating three key decisions. In order of descending merit, these were: (1) For NASA to subsidize the development of private launch systems for delivery of astronauts to the International Space Station, (2) Cancellation of the Constellation program devoted to developing a hardware set for enabling piloted missions to the Moon, and (3) Abandonment of the concept of setting any specific mission goal for NASA’s human spaceflight program in favor of an approach based on funding technology research for the purported purpose of better enabling some mission that might be selected later. The first of these is positive decision that is long overdue. The second, taken in itself, is harmful, but could be made good, were something better proposed in Constellation’s place. The third, however, is a horrible mistake, that, if accepted, would guarantee zero accomplishment for the American human spaceflight program for the foreseeable future. Over the course of its history, NASA has employed two distinct modes of operation. The first, which has always been the method of the robotic exploration effort, but which prevailed in the human spaceflight program only during the period from 1961-1973, may therefore be called the Apollo Mode. The second, prevailing within the human spaceflight effort since 1974, may usefully be called the Shuttle Era Mode, or Shuttle Mode, for short. In the Apollo Mode, business is conducted as follows. First, a mission goal is chosen. Then a plan is developed to achieve this objective. Following this, hardware designs are developed to implement that plan, and if necessary, new technologies are created to enable such hardware. The hardware set is then built, after which the mission is flown. The Shuttle Mode operates entirely differently. In this mode, technologies and hardware elements are developed in accord with the wishes of various technical communities. These projects are then justified by arguments that they might prove useful at some time in the future when grand flight projects are initiated. Contrasting these two approaches, we see that the Apollo Mode is destination driven, while the Shuttle Mode pretends to be technology driven, but is actually constituency driven. In the Apollo Mode, technology development is done for mission directed reasons. In the Shuttle Mode, projects are undertaken on behalf of various internal and external technical community pressure groups and then defended using rationales. In the Apollo Mode, the space agency’s efforts are focused and directed. In the Shuttle Mode, NASA’s efforts are random and entropic. Imagine two couples, each planning to build their own house. The first couple decides what kind of house they want, hires an architect to design it in detail, then acquires the appropriative materials to build it. That is the Apollo Mode. The second couple polls their neighbors each month for different spare house-parts they would like to sell, and buys them all, hoping to eventually accumulate enough stuff to build a house. When their relatives inquire as to why they are accumulating so much junk, they hire an architect to compose a house design that employs all the knick-knacks they have purchased. The house is never built, but an adequate excuse is generated to justify each purchase, thereby avoiding embarrassment. That is the Shuttle Mode. In today’s dollars, NASA average budget from 1961-1973 was about $18 billion per year. That is the same as NASA’s current budget. To assess the comparative productivity of the Apollo Mode with the Shuttle Mode, it is therefore useful to compare NASA’s accomplishments between 1961-1973 and 1998-2010, as the space agency’s total expenditures over these two periods were equal. Contrasting the brilliant record of achievement of NASA’s human spaceflight program during the Apollo period with that of the past decade speaks for itself. In technology development, the Apollo era NASA was also far superior, creating hydrogen oxygen rocket engines, multi-staged heavy-lift launch vehicles, nuclear rocket engines, space nuclear reactors, radioisotope power generators, spacesuits, in-space life support systems, orbital rendezvous techniques, soft landing rocket technologies, interplanetary navigation technology, deep space data transmission techniques, reentry technology, and more. In contrast, during the past 13 years, no new technologies of any significance were actually developed. The only area in which the achievements of the current NASA compare with that of its Apollo period self is robotic planetary exploration. But this is precisely because the JPL-led robotic planetary exploration effort continues to use an Apollo-style mission-driven approach. In the JPL program, missions are selected based on rational science-driven criteria, designs are then drawn up, and if necessary, technology work is undertaken to help implement those designs. If instead, JPL chose to spend most of its funds in development of random technologies, and then designed its missions around the purpose of employing such toys for their own sake, its productivity would fall to nil as well. Consider the following; At the same time it announced its new space policy, NASA gave notice that the three key new supposedly “game changing” inventions it would seek to develop as part of the effort would be the VASIMIR electric plasma propulsion drive, orbital space depots, and heavy lift technology. But the VASIMIR thruster, while energetically advocated by its inventor, offers no clear mission benefits over existing ion drive electric propulsion systems, and both remain completely useless as tools for supporting human exploration missions in any role without the development of multi megawatt space nuclear reactors to power them, which is not part of the program. Furthermore, even if such huge space nuclear power systems were created, the claim that VASIMIR (or any other electric thruster) would then enable transits to Mars with much shorter flight times than existing chemical propulsion systems (or even equal flight times to those available from existing rockets) simply has no basis in technical reality. So stalling a Mars program while awaiting for such magic-based capabilities to materialize is just a prescription for having the human spaceflight program continue to mark time. As for the orbital propellant depot, this was a favorite hobbyhorse of one of the members of the Augustine Committee responsible for recommending the new policy. Its potential utility, however, as a way to enable human Moon, near Earth asteroid, or Mars missions is completely unestablished. To the contrary, none of NASA’s recent designs for Moon or Mars missions have involved refueling spacecraft from orbital propellant stations. To insist that mission architects adopt such a strategy because “this is the technology we are working on” is to force the program to accept a suboptimal system design based on an arbitrary decision to favor one technology. Finally, it is simply not the case that we need new technologies to create heavy lift launch systems – we flew our first heavy lifter, the Saturn V in 1966. What is actually needed to give us a functioning heavy lift booster is a decision to build it, which will never come until there is mission to employ it. Thus, without the guidance supplied by a driving mission, under the new Obama space policy, another ten years and upwards of a hundred billion dollars will be spent by NASA’s human spaceflight program without achieving anything significant. We may take part in another 20 flights to low Earth orbit, but there is no new world there to explore. Together with the Russians, we have already flown there some 300 times over the past half century. Spending a kings ransom to raise that total to 320 is hardly seems worthwhile. Under the Obama plan, we may develop some new technologies, but without a mission plan to guide their selection, they won’t be the right technologies, they won’t be realized as actual flight systems, they won’t fit together, and they won’t take us anywhere. The American people want and deserve a human spaceflight program that really is going somewhere, and not just anywhere, but to a destination that is really worth going to. That destination is Mars. For the past four decades since the end of Apollo, Mars is the challenge that has stared the American space program in the face. A world with varied resources and a past history that includes oceans of liquid water, Mars is the Rosetta Stone that will tell whether the development of life from chemistry is a general phenomenon in the universe, and whether life as we know it on Earth is the pattern for all life everywhere, or alternatively that we are simply one esoteric example of a far vaster and more interesting tapestry of possibilities. Moreover, Mars is the closest world that truly has the resources needed for human settlement. For our generation, and those which will follow, Mars is the New World. We should not shun its challenge. But regardless of what destination we choose, what is absolutely primary is that there be a destination, which defines a mission plan, which defines a hardware set, which then defines what technologies should be developed and what hardware elements will be procured. If matters are approached this way, there are many methods of procurement of flight systems that can be used, including both conventional and entrepreneurial approaches, but they need to be employed coherently to achieve a defined objective. If this is not done, then ten years from now, after spending another $100 billion on human spaceflight, we will be no closer to sending astronauts to the Moon or Mars than we are today. The Obama administration claims that its new space policy enables a “flexible path.” In reality, it is a prescription for yet another wasteful random walk. Four decades of stagnation in space is enough. If any progress is to made, a course must be set. Leadership is required. In the beginning, there was the Word.
Mars Society Switzerland
NASA Needs a Destination an answer to President Obama
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