Critics of human spaceflight have a saying: "If God had wanted people to go into space, He wouldve given them more money." This reworked adage has never seemed more appropriate than during the recent battles in Washington, D.C., over the future of the space shuttle and the International Space Station (ISS). Both programs are facing severe cutbacks as NASAs new administrator, Sean OKeefe, tries to bring order to the space agencys troubled $15-billion budget. It is likely that NASA will have to reduce the number of shuttle flights and scale back the assembly of the space station, at least temporarily. After a decade of poor planning, the space agency is hoping to salvage what it can.

The profligacy of the space shuttle is well known: each flight costs about $500 million. In the mid-1990s, NASA initiated the X-33 program to produce a more cost-effective, fully reusable craft that could reach orbit with just one rocket stage. (The shuttle, in contrast, is a two-stage vehicle that jettisons a pair of solid-fuel boosters during its ascent to lessen the mass lifted into space.) But such a craft would have to carry 10 times its weight in fuel, and the new technologies needed to reach that goalsuch as the use of lightweight composite materials for fuel tanksproved more troublesome than expected. After five years of effort, NASA canceled the program. The total cost: $912 million for NASA, $357 million for contractor Lockheed Martin.

A New Tack

Last year NASA decided to go back to the drawing board. Under its Space Launch Initiative (SLI), the agency plans to spend $4.8 billion by 2006 to develop the technologies needed to build a replacement for the shuttle. NASA has already awarded nearly $900 million in contracts to 22 companies and universities, with much of the work focused on new rocket engines and airframes. The agency is now reviewing preliminary vehicle designs proposed by Lockheed, Boeing and a joint team consisting of Northrop Grumman and Orbital Sciences. Burned by its experience with the X-33, NASA has relegated the idea of a single-stage craft to the far future (that is, around 2025). Judging from the preliminary designs, the successor to the shuttle will most likely have one or more liquid-fuel boosters that would be able to fly back to the launch site after separating from the orbiter. Because liquid-fuel rockets can be throttled up and down by varying the flow of fuel, they have an inherent safety advantage over the shuttles solid-fuel boosters.

But the $4.8-billion program will not actually produce a spacecraft; NASA plans merely to choose a design by 2006 and then build the vehicle over the following six years. And in Congressional hearings in April, NASA officials acknowledged that this timetable is probably too ambitious and that the shuttles successor may not start flying until after 2020. What is more, budgetary shortfalls have forced the space agency to curtail some of the upgrades that were intended to ensure the safety of the aging shuttle fleet until the second-generation vehicles go into operation.

The Aerospace Safety Advisory Panel, an independent group of experts that analyzes the shuttle program, warned in its annual report that NASAs financial problems were putting astronauts at risk. Richard D. Blomberg, the panels former chairman, issued a blunt admonition in his testimony to the House Subcommittee on Space and Aeronautics: "In all of the years of my involvement, I have never been as concerned for space shuttle safety as I am right now. That concern is not for the present flight or the next or perhaps the one after that. In fact, one of the roots of my concern is that nobody will know for sure when the safety margin has been eroded too far. All of my instincts, however, suggest that the current approach is planting the seeds for future danger."

Costly Problems

Financial woes have also buffeted the ISS, the orbiting construction site that has been the destination for most of the current shuttle flights. Over the past four years, estimates of the cost of assembling the 500-ton station have soared from $17 billion to more than $30 billion. In November 2001 the ISS Management and Cost Evaluation Task Force concluded that NASAs plan for completing the station was "not credible" because of overoptimistic cost estimates and poor management. O'Keefe, who became NASA's administrator the following month, swiftly acted on the task forces recommendations.

In the 2003 budget request that NASA submitted in February, the agency made it clear that it intends to fund only four space shuttle flights a year (down from six or seven), the minimum number needed to support the ISS. The station itself was put under a kind of probation: until the program managers learn to live within their budget, NASA will assemble only the core of the orbital outpost and will postpone the addition of several modules. The space station now accommodates just three astronauts; to support a full crew of seven, the station needs another habitation module as well as a Crew Return Vehicle that can evacuate all the astronauts in case of a disaster. (The station's current "lifeboat" is a Russian-made Soyuz craft, which can hold only three people.)

NASA's partners in the ISSthe space agencies in Europe, Japan, Russia and Canadareacted furiously to the American plans. Noting that the stations primary goal is to conduct experiments in space, the international partners argued that a three-person crew is simply not large enough to conduct a serious research program. Because the station is a fairly sophisticated piece of machinery, at least two crew members must devote the bulk of their time to maintaining it. "A three-person crew will not be able to conduct science that is consistent with the level of investment that everybody has made," said Doug Bassett of the Canadian Space Agency at a meeting of the NASA Advisory Council. Bassett quoted a Canadian politician as saying that the station could become "the biggest white elephant in the history of humanity."

Safe Options?

One solution to this quandary would be to dock two Soyuz lifeboats to the ISS. This move would enable the station to hold a crew of six and would probably be less expensive than developing the Crew Return Vehicle. Another idea would be to enhance the stations "safe havens"the modules to which astronauts can retreat if an accident disables part of the ISS. OKeefe is considering both options.

What makes NASAs budget troubles so disheartening is that so many experts had anticipated these problems long ago, and yet the agency refused to change course. When the shuttle was being designed in the 1970s, NASA unwisely chose to build a vehicle with high operating costs because it would reduce the expense of initial development. And during the planning of the ISS in the 1980s and 1990s, a number of scientists warned that the projects estimated cost far exceeded the potential value of the research to be conducted on the station. Just as the scientific community predicted, the financial shortfalls of the ISS have forced NASA to shift funds from unmanned missions that have a far greater chance of yielding important discoveries. The agency desperately needs to balance its books before further damage is done to the program of space exploration.

Mark Alpert is on the board of editors of Scientific American.