WASHINGTON — NASA’s new science chief, Alan Stern, used his first appearance before Congress to put principal investigators on notice: keep your missions on budget or prepare to step aside.

Stern, an experienced principal investigator (PI) with his own NASA-funded spacecraft hurtling toward Pluto, said scientists lucky enough to have their mission proposals selected by NASA have an obligation to put their research duties on hold and focus on getting their spacecraft and instruments built.

“If their view of a PI-led mission is that the PI is led around, then they are at risk and we will find somebody who can do it better,” Stern told the House Science and Technology space and aeronautics subcommittee during a May 2 hearing on NASA’s science budget.

“If their view of a PI-led mission is that the PI is led around, then they are at risk and we will find somebody who can do it better.” — Alan Stern

Holding principal investigators accountable for the budget performance of their programs is just one of the ways that NASA intends to make better use of the roughly $5.4 billion a year it currently devotes to science, Stern said.

The agency also has begun requiring its regional field centers to be more conservative when they estimate costs for the programs they are assigned to do, he said.

As ambitious as the NASA science program is with 52 spacecraft in orbit and 41 new flight missions in development for launch over the next seven years, Stern told lawmakers, the agency “would in fact have more missions in development on the same budget were we better able to control costs, and I am setting out to do that.”

The three scientists who shared the witness table with Stern praised his ideas for getting the most out of NASA’s science budget. But they also said NASA in general, and Stern’s Science Mission Directorate, in particular, need more money to do all that they has been asked to do.

Lennard Fisk, a former NASA science chief who chairs the National Research Council’s Space Studies Board, noted that $3 billion to $4 billion was taken from NASA’s science budget to pay for shuttle return to flight and completion of the international space station. “There is no way to remove that much money from the budget without causing disruptions to ongoing programs and a distortion to the balance among programs.”

Fisk said the obvious remedy for what ails science at NASA would be to “get back the money that was lost.”

“A more constructive way to make that statement is to note how inadequately NASA as an agency is funded,” Fisk said. “It is being asked to do much with too little and as a result all components of the agency, including science, are sub-optimally funded. We should all make it a strategic goal to provide NASA with the funding that is required.”

Rep. Mark Udall (D-Colo.), the subcommittee chairman, clearly had gotten the message before the hearing had even begun. In his opening statement, Udall pointed out that in the three years since U.S. President George W. Bush unveiled the Vision for Space Exploration, the White House has cut $4 billion from its previously planned requests for NASA science expenditures.

“At a time when NASA’s science programs offer the promise of major advances in our understanding of the sun, our solar system, and the universe beyond, we risk doing long-term damage to the health of those programs if we are not careful,” Udall said. “If we are going to ask our nation’s space science program to undertake challenging and meaningful initiatives, we are going to need to provide the necessary resources.”

The subcommittee’s ranking Republican, Rep. Ken Calvert of California, also said he thinks NASA is under funded. But he also expressed sympathy for the decisions NASA Administrator Mike Griffin has made within the constraints of the agency’s limited budget.

“I don’t fault NASA for making the tough choices it did, but it shouldn’t be that way,” Calvert said, calling on the Bush administration to provide more funding for NASA.

Stern said he intends to bring greater efficiency to a Science Mission Directorate many of his fellow scientists have lamented as woefully cash-strapped. ” I want to turn heads while I am here,” Stern said. “I want to produce landmark scientific achievements and to make my directorate and its various projects run more efficiently and stay within their cost boundaries.”

Stern identified rising launch costs, cost growth in mission development and unrealistic cost estimates put forth by the so-called decadal surveys that shape NASA’s science agendas as the major challenges facing the directorate.

But he also vowed to increase funding for research and analysis — a budget area especially hard hit in recent years to the chagrin of grant-funded scientists and technology developers — and put more support behind the agency’s suborbital launch programs in order to “train space scientists in the art of space flight and bridge the 2010 to 2012 desert in orbital launches and provide opportunities for technology development and demonstration.”

Scientists have been calling on NASA since early last year to restore funding for small- and medium-sized missions selected through periodic competitions.

In a show of good faith, Stern said NASA intends to move an Explorer-class mission competition two months to October of this year.

NASA also plans to use the forthcoming Explorer announcement of opportunity to impose more stringent experience requirements for scientists wanting to lead missions, Stern said.

“We are calling for a minimum experience level for the principal investigators themselves.” Stern said. “Previously there was no minimum experience level, so a scientist who had not been involved in space flight could write a sufficiently good proposal and lead a team to win and sometimes that gets you in trouble. You may wake up in the morning and want to do brain surgery but doesn’t mean you can do it.”

Fisk, alluding to the role NASA oversight plays in driving up mission costs, said he supported Stern’s plan to establish stricter prerequisites for principal investigators provided the agency then stands back and allows them to perform.

“Choose experienced PIs. That’s a good thing,” Fisk said. “But if they are really experienced, let them do the program in such a way that they can produce [the mission] in the most cost-effective way possible.”

Launch costs also were discussed during the hearing, with Calvert asking how NASA intends to meet future launch needs without the Delta 2 rocket.

Stern said the current Delta 2 inventory is sufficient to fly out all the missions NASA has on the books through 2012 and noted that the agency has been using air-launched Pegasus rockets for smaller payloads.

“We are looking at some alternatives to or additions to those possibilities to give us low-cost access to space again for small- and moderate-sized missions,” Stern said. “Decisions have not been made but I can assure you that it’s important not only to the Science Mission Directorate but also the larger agency.”

Scientists are eagerly awaiting NASA’s decision. “It has to be a robust solution,” Fisk said. “It can’t be simply keep the
Delta 2 alive because that would probably be too expensive.”

Daniel Baker, a heliophysicist at the University of Colorado, Boulder, said shifting all NASA launch traffic to the larger Atlas 5 and Delta 4 rockets also presents problems. “Going to larger launch vehicles immediately adds tens of millions of dollars to those missions’ costs.

By taking the cap off mass constraints, it can allow for unexpected growth in missions,” he said. “I think we would be well advised to try to restore that capability or make sure we have something comparable to the Delta 2 to enable these missions.”

Brian Berger is editor in chief of SpaceNews.com and the SpaceNews magazine. He joined SpaceNews.com in 1998, spending his first decade with the publication covering NASA. His reporting on the 2003 Space Shuttle Columbia accident was...