- By Stephen M. WaltStephen M. Walt is the Robert and Renée Belfer professor of international relations at Harvard University.
Explanatory Note: A couple of weeks ago, I read a news story about how museums around the country were competing to exhibit the retired space shuttle Discovery, after its long and supposedly distinguished career. That’s not surprising, of course, as having a shuttle on display would undoubtedly be a big draw for a lot of museums. What troubled me was the suspicion that future museum exhibits would depict the whole shuttle program in laudatory terms, instead of treating it as an foolish diversion of national resources. Space policy isn’t really my thing, however, and I said to myself: "You know, you’d need a rocket scientist to write this properly!" Fortunately, I have one available: my father. He’s a geophysicist who spent much of his career designing satellite packages and interpreting the data they produced, so I asked him if he’d be willing to contribute a guest post on the topic. Here’s what he sent in. — S.M.W.
By Martin Walt IV
Recent news columns have commemorated the retirement of the Space Shuttle orbiter Discovery. It is indeed noteworthy that this vehicle experienced some 39 launches and traveled 150 million miles in near-Earth space. This achievement was made possible by the imaginative engineers and scientists who conceived the Shuttle program and developed the necessary technical innovations. Recognition must also be given to the dauntless flight crews — both military personnel and civilians — whose courage and dedication were outstanding, especially those astronauts who volunteered to fly after two orbiters were lost in accidents that revealed serious weaknesses in the hardware and in NASA’s managerial culture.
NASA and amateur space enthusiasts portray the Shuttle program as a resounding success, but a more sober appraisal of the program’s impact leads to a much less favorable verdict. The Space Shuttle was expected to provide inexpensive and reliable access to space for a multitude of missions. It never came close to achieving this goal. In retrospect the goal proved impossible due to high refurbishment costs, program delays, and the inappropriate use of humans where robots would have been better. To promote shuttle use and spread fixed costs over many flights, the Expendable Launch Vehicle (i.e., disposable rocket) programs were discontinued, so that all civilian missions could be diverted onto the Shuttle. Yet instead of being inexpensive, a single launch required approximately $1B. Schedules were compromised by endless delays and by the inspections needed to verify that the complex machinery was ready to transport humans safely. NASA underestimated the time required to service the orbiters between flights, and the launch frequency never approached the advertised rate, leading to a substantial backlog of payloads, both scientific and applied, awaiting launch. The resulting delays in science programs reached a crisis when the Challenger orbiter was lost, in effect putting America’s scientific space effort on hold for over two years. Fortunately for the country, the Air Force had maintained its own Expendable Launch Vehicle capability, and the high priority surveillance satellite programs were not grounded during that period.
It is difficult to estimate the overall direct and indirect cost of the Space Shuttle program, but it must be well over $100B. As these overruns occurred, funds to pay for them were extracted from the science projects the Shuttle was intended to support. Costs of science experiments launched by the Shuttle were also inflated by the need to certify the instruments as "man rated." Even such unique feats as repairing the Hubble Space Telescope seem less meritorious when one realizes that the repair mission expense was $1B and put astronauts lives at risk. That same $1B could have been used to build and launch a new Space Telescope. In short, the Space Shuttle Program was enormously expensive, led to a tragic loss of human life, and contributed little to science other than launching of scientific payloads which could have been placed in orbit better by expendable vehicles.
The debate on the value of the Space Shuttle Program is but one facet of the manned vs. unmanned space flight controversy that has raged for decades. Proponents of the unmanned or robotic approach to space exploration cite the vastly lower cost, the lack of astronaut risk, and the ability to make one-way trips to distant places. It follows that unmanned programs are essential for the advancement of science in space.
By contrast, manned space enthusiasts assert that having human intelligence on-site is important, that man’s destiny is to explore, and that young people are inspired by the challenge of putting humans in space. They also claim that public support for the space program, both manned and unmanned, would decline if humans were not involved in flight. The merits of these arguments are debatable, but perhaps there is a role for human beings in some space experiments. However, the Shuttle Program illustrates the dangers, both financial and programmatic, of making humans the central feature of our outer space endeavors. Unfortunately, we seem likely to repeat this mistake with the International Space Station, and if we do, the United States will spend enormous sums and talent for few tangible results.