Simon “Pete” Worden might be scratching his head these days wondering why he accepted the job as director of NASA’s Ames Research Center at Moffett Field, Calif., this past spring. Certainly no one could blame him.

The retired U.S. Air Force brigadier general, who developed a reputation in the service for his commitment to low-cost innovation in space activity, came to NASA with the expectation of having a role to play in U.S. President George W. Bush’s Vision for Space Exploration. After all, Ames had management responsibility for the robotic orbiters and landers that are being planned to pave the way for the return of human explorers to the Moon.

But Mr. Worden was barely a month in the job when that responsibility was abruptly transferred to NASA’s Marshall Space Flight Center in Huntsville, Ala., for reasons that remain murky. NASA’s official explanation was that the move would result in better programmatic synergies since Marshall is charged with developing a robotic lunar lander that would launch in 2011. Some NASA officials added privately that Ames was not up to the task of managing the robotics program, but a pair of internal agency reports suggest otherwise.

In what might best be described as a consolation offering, Ames was given the lead role in developing information technology and thermal protection systems for the exploration effort. Perhaps more significantly, the center, better known lately for supercomputing research than for managing space missions, was given the go-ahead to set up a lunar projects office for designing small missions that would support the broader program.

For Mr. Worden, who came to Ames intent on establishing a hotbed for low-cost yet scientifically relevant missions, the lunar projects office was something he could sink his teeth into. And in fact he did, producing a conceptual exploration architecture featuring small robotic missions mixed in with larger ones already in the queue, such as the Marshall lander and the Lunar Reconnaissance Orbiter, which is being developed by Goddard Space Flight Center in Greenbelt, Md., and slated to launch in 2008.

NASA sources say the architecture, highlighted by a microlander that would launch in 2008 to conduct precursor activities and demonstrate progress toward the goal of returning astronauts to the Moon by 2020, was a hit with several senior agency officials. With the knowledge of Tony Lavoie, manager of NASA’s lunar robotics program, Ames went ahead in mid-July with solicitations for propulsion hardware for the microlander.

In explaining NASA’s decision to cancel the solicitations two weeks later, Mr. Lavoie said growing costs associated with the space shuttle and its replacement vehicle were putting pressure on his program, which is no doubt true. NASA Administrator Mike Griffin, meanwhile, reaffirmed the agency’s commitment to launch the Goddard orbiter and Marshall lander in 2008 and 2011, respectively, effectively putting Mr. Worden’s plan third in line in terms of priority.

It is clear that funding pressure was the main reason NASA pulled the plug on the proposed 2008 microlander: Everyone knows that NASA’s plate of missions and priorities is far bigger than its budget, current or projected. But the fact that NASA was quick to notify the office of Sen. Richard Shelby (R-Ala.), the chairman of the Senate Appropriations subcommittee responsible for funding the agency, about the cancellation illustrates that these kinds of decisions are not made in a political vacuum.

Given that similar programs necessarily compete head-to-head when budgets get tight, it is fair and reasonable to assume that Mr. Worden’s plan came to be seen by Marshall and its supporters as a threat. At minimum, it would siphon precious dollars away from the Alabama center. And with the main lander expected to cost in the neighborhood of $500 million, Mr. Worden’s lower-cost approach was bound to be seen in some circles as an alternative.

But just as it would be nave to believe that politics have no bearing on where NASA spends taxpayer funds, it would be unfair to jump to the conclusion that the agency simply caved to the whims of Alabama’s powerful congressional delegation in this matter.

What is for certain is that, barring an infusion of cash, NASA would have to reorder its priorities in robotic lunar exploration to accommodate elements of Mr. Worden’s proposed architecture, something Mr. Griffin clearly was unwilling to do.

The question people should be asking now is whether NASA — given all of the political and budget constraints it faces — will ever be able to find room for investments in promising alternative approaches to exploration. Congress and NASA need to find a way to fund such programs because they have the potential to pay for themselves many times over in the years ahead.