Times are tough for the Universe. No not that universe, NASA's $1.5 billion-Universe.

When the U.S. space agency reorganized its mission enterprises last year, it combined all of its astronomy programs into a single program dubbed the Universe. Today, the Universe has more than a dozen space astronomy missions on orbit and at least that many in development.

Between paying for the space shuttle program and funding new forward-looking space exploration projects like the Crew Exploration Vehicle, NASA's budget for the Universe is not getting any bigger. In fact, NASA's 2006 budget calls for spending slightly less on the Universe than in 2005, even as the Universe is seeing significant cost growth on some of its highest priority projects.

The projected price tag for the James Webb Space Telescope, for example, has swelled by another $1 billion to $4.5 billion. That unpleasant surprise prompted NASA to seek ways to scale back the mission and erode the cost increase without dealing a fatal blow to the program's science objectives.

Another high priority mission, an extrasolar planet finder called the Space Interferometry Mission (SIM), is facing a $500 million overrun. Kepler, a less sophisticated planet finder once scheduled to launch in 2007, is now facing a delay of undetermined length.

An airborne telescope called SOFIA and the Gamma Ray Large Area Space Telescope slated for launch in 2006 are encountering minor setbacks on their way to service, with both requiring more money.

And with NASA leaning toward sending a space shuttle crew to repair and upgrade the Hubble Space Telescope, the space agency's strapped Universe budget is going to have to bear at least part of the cost of the estimated $750 million undertaking.

Rick Howard, NASA's deputy director of the Universe, acknowledged that budgets are tight and that something is going to have to give to pay for Hubble servicing and astronomy projects that are close to first light, but he said cancellation is unlikely for either the Webb telescope or SIM despite their soaring price tags.

"Given that Hubble [servicing], SOFIA and the Gamma Ray Large Area Space Telescope are in development, increases in those are going to have impacts on the other programs," Howard said. "But cancellation? No."

NASA has already indicated that it is not willing to absorb the full $1 billion cost increase on Webb, so the agency plans to convene a group of senior scientists this summer that will help the

agency decide how much to scale back the telescope and what other projects to cut to help pay any remaining overrun.

"Everybody loves [the James Webb Space Telescope] and the science it can do," Howard said. "On the other hand there is an upper dollar limit at which the science community says it's not worth doing. So it's a balance."

NASA is going through a similar exercise with SIM.

Last year, the Jet Propulsion Laboratory, Pasadena, Calif., informed NASA that SIM was going to cost about $500 million more than the $900 million the agency had budgeted for the planet-hunting mission.

"We said we cannot afford that," Howard said. "So we looked at what we thought we could afford."

Howard said the SIM team was told to plan two versions of the mission: one that could be built for $1 billion and one that could be constructed for $1.2 billion.

The SIM team is due to go back to NASA Headquarters in mid-July with the revised mission. Howard said NASA will then decide how to proceed and establish a new launch date. A revised 2005 spending plan NASA sent to Congress in May, however, indicates that SIM's launch will be delayed two years to 2013.

Kepler, a cost-capped Discovery-class mission, is in a different situation. Howard said the mission was coming along well, but had to absorb a $35 million budget hit this year to help fund other pressing priorities NASA's Science Mission Directorate was facing. Howard said NASA has not set a new launch date for the mission, but expects it to slip about a year from its previously planned 2007 date.

Joseph Alexander, director of the National Research Council's Space Studies Board here, said astronomers are understandably nervous about what the future holds for both big and small space observatory projects at NASA.

"It's going to be a real challenge for NASA to go forward with the space exploration vision and to do it in a way that preserves a science program that is both robust and broadsided," Alexander said. "We are probably seeing the most acute situation with the astronomy program where they are seeing big jumps in cost."

Alexander said that in absolute dollar value, NASA's astronomy program appears to be seeing the most cost growth of any of NASA's science programs -- a circumstance, he said, due at least partly to the "intrinsic complexity" of the missions now in development.

David Black, president of the Universities Space Research Association in Houston, said the science community is partly to blame for the situation NASA's astronomy program is in today.

Black said that while most of NASA's current budget problems can be traced back to the loss of the Space Shuttle Columbia and the cost of getting back to flying again, while other parts of NASA, aided and abetted by the science community, have contributed, he said, "by trying to do too much with too little."

"That works if all goes as forecast, but with the incredibly complex missions, requirements creep, and other factors, all of the missions in recent memory have ended up costing substantially more than they were advertised to be," Black said. "There may be some element of 'getting the nose under the tent,' but NASA should be able to calibrate that by now. I think it is more that the technology is hard, and we keep finding 'desirements' becoming 'requirements'."

Another factor, Black said, is NASA's move to full-cost accounting, or making programs pay for every man hour they use in completing a project. "My observation is that few, if any, of the [NASA field] centers really got it right when they had to estimate their costs so that we are now seeing the cost of civil service manpower at some centers going through the roof," Black said. "That was never adequately budgeted."

Both Black and Alexander said it is not clear how exactly NASA's astronomy program will find its way through its current predicament.

"The approach when Ed Weiler was associate administrator was very clear," Alexander said. "Ed held his divisions responsible for solving their own problems internally. If things are done the way they were in the past, Anne Kinney [director of the Universe] will have to look across her programs to solve these problems and she can't expect [NASA Associate Administrator for Science] Al Diaz to go elsewhere to solve her problems."

Alexander did not say what projects he thinks Kinney would cut to solve pressing budget demands, but he said he expects she will not tap into the money NASA sets aside to fund scientific research grants.

"She knows she cannot dip into those because then she would be building missions but there would be no astronomers to reap the benefits of the missions. I know she is very conscious of that issue."

Black, who said he sees a "slim possibility" that Congress will come through with enough extra money to fully fund a Hubble servicing mission even though Congress has made clear it wants NASA to do it, said the space science community "should probably expect a squeeze, or at least our share of the pain" in these tight times.

Black said he expects that NASA Administrator Mike Griffin, himself a scientist, will "do everything he can to keep the science programs healthy."

"[H]aving an administrator who understands and values science is a good thing as contrasted to someone whose world view is a column of numbers and the bottom line," Black said.