NASA will be listening when scientists present their recommendations for the next decade of astrophysics research Friday, but some of the proposed missions could be at the mercy of soaring costs on the $5 billion successor to the Hubble Space Telescope.

Artist's concept of the James Webb Space Telescope. Credit: NASA/ESA

The National Research Council will release its priorities for space and ground observatories at 11 a.m. EDT Friday. NASA uses the decadal survey's recommendations to shape its portfolio of future missions.

But the execution of new programs depends on the agency's budget, and much of NASA's funding for astrophysics missions is being gobbled up by the James Webb Space Telescope, an infrared facility to be stationed a million miles from Earth that will peer deeper into the universe than ever before.

Jon Morse, the director of NASA's astrophysics division, says JWST's rising cost is putting future missions in jeopardy.

"It is highly constraining our ability to move on with any new missions," Morse said in a July 27 interview.

Astrophysics missions probe the universe and address fundamental questions about its formation, evolution and structure. Some platforms study objects within the Milky Way galaxy, searching for extrasolar planets or looking into star-forming regions to see the births of solar systems.

According to Morse, NASA transferred $20 million in funds from other projects to JWST in 2010. The agency requested another $60 million be added to the observatory in fiscal year 2011, which begins in October. Those additions come after an extra $175 million was needed by the JWST program in 2009, including transfers from within the NASA budget and government stimulus funds.

The 2011 budget proposal calls for nearly $445 million in spending for JWST next year.

"There have been many offsets from the rest of the astrophysics portfolio in order to try to keep JWST as close to on-track as we can make it," Morse said.

Lynne Hillenbrand, a member of the decadal survey panel, told Spaceflight Now the report considers funding constraints and will offer several different budget scenarios for execution of its recommended missions.

According to Hillenbrand, a professor at the California Institute of Technology, the National Research Council received a briefing from NASA on the JWST budget woes. The scientists also received budget projections based on President Obama's fiscal year 2011 budget request and forecasts for future years.

"We have not had a report from NASA since earlier in the year and knew over the intervening months only the same publicly available information as everyone else regarding JWST," Hillenbrand said Aug. 6.

Officials say NASA's ability to have a balanced family of missions, including a mix of flagship-class and focused less expensive projects, ensures the richest return of scientific data.

"We're trying to make sure we have a robust plan with JWST, but keeping in mind that our goal is to have a balanced portfolio here of small, medium and large missions that the community has asked for," Morse said. "Right now, we do."

But NASA is committed to launching JWST as close as possible to its June 2014 target. The telescope already takes up about 40 percent of the agency's astrophysics budget.

Six of JWST's 18 mirror segments undergo cryogenic testing. Credit: NASA/MSFC/David Higginbotham/Emmett Given

"What I've been telling the community, like the decadal survey panel, is the cheapest JWST is the one that launches the soonest, which is why we want to keep it on schedule," Morse said.

Starting new projects is nice, Morse said, but missions don't produce data until they are safely in space.

"Our success criteria, in my mind, is how many fires we light on the launch pad and how much science we're returning. It's not how many new projects we start. We want to finish the projects. We're trying to finish JWST and get a robust plan that we can stick to."

The decadal survey, on the other hand, is focused on kicking off new missions. The report will consider projects with international partnerships, most of which would launch after 2020.

Getting JWST launched by June 2014, or at least close to that date, will almost certainly require more money than predicted today. Multiple ongoing reviews of JWST's budget posture and the mission's upcoming test campaigns are expected to produce reports later this year.

"JWST appears to need a larger share of the budget, and there will be offsets elsewhere in the portfolio, particularly in executing new missions that will be in the future years," Morse said.

Sen. Barbara Mikulski, D-Md., wrote NASA Administrator Charlie Bolden in June calling for an external review to determine the most expedient and least expensive way to complete JWST.

Northrop Grumman Corp., the observatory's prime contractor, has already provided forecasts of what it will need to finish its part of the project as scheduled.

"From a Northrop Grumman perspective, we have provided different scenarios for them on what funding would be required and what reserve positions to support a June of 2014 launch date," said Scott Willoughby, the Northrop Grumman JWST program manager. "We've given that data and we've also given them data on different scenarios where particular years are constrained and we let other years move, or where we've looked at schedule against funding."

Willoughby declined to discuss specific numbers until the reviews are complete, but sources say the funding estimates would exceed current budget projections, meaning more unplanned money allocations will be necessary in the coming years.

"We have independent panels, the standing review board, for example, helping the project assess what the proper risk posture is from schedule and budget standpoints," Morse said.

After spending $2 billion on JWST's formulation and preliminary design, NASA approved the mission to proceed into full development in a 2008 confirmation review.

"When we went through the confirmation review in 2008, we put in a budget all the way out to launch in 2014, which, at the time, was deemed to have adequate cost reserves," Morse said. "Those (subsequent) offsets came from the rest of the portfolio, mostly from our ability to do additional missions."

JWST, then called the Next Generation Space Telescope, was the top-ranked recommendation the last astrophysics decadal survey released in 2001.

The mission promises to search for the first galaxies or light-emitting objects after the Big Bang, chart the history of galaxy formation, track the evolution of stellar systems, and make chemical maps of planets, stars and galaxies.

The observatory's four instruments haven't been immune to cost growth and delays. The University of Arizona's Near-Infrared Camera, or NIRCam, has quadrupled in cost in the past decade, according a July 16 report in Space News.

Two other instruments are scheduled to start acceptance testing in September, but one of the payloads is still waiting on components from NASA's Jet Propulsion Laboratory, according to Peter Jensen, the European Space Agency's JWST project manager.

"NASA cost problems have had no to little impact on ESA JWST activities up to now," Jensen wrote in an e-mail to Spaceflight Now. "We are focused to finish our instrument development according to our schedule in order to be as cost efficient as possible."

ESA has received flight detectors and micro-shutters from NASA's Goddard Space Flight Center to go in the Near-Infrared Spectrograph, or NIRSpec. Problems with electronics in the Mid-Infrared Instrument, or MIRI, delayed the shipment of its detectors from JPL, according to Jensen.

Cryogenic testing of JWST's instrument module. Credit: NASA/GSFC

Acceptance testing for NIRSpec and MIRI should be complete by the spring or summer of 2011 if it begins in September, Jensen said.

The telescope's 18 primary mirror segments are going through cryogenic testing at NASA's Marshall Space Flight Center to detect tiny imperfections as the material cools from ambient temperature to -415 degrees Fahrenheit, close to the required operating temperature for JWST to reach its peak sensitivity.

A giant sunshield the size of a tennis court, along with on-board coolant, will ensure the telescope's instrumentation stays cold.

"The queue is loaded with mirrors moving through the system," Willoughby said Aug. 2.

Technicians will correct the surface errors with further polishing, then send the mirrors back to Marshall to check that they meet flight specifications.

Willoughby said all 18 mirror segments are built.

"They're not complete in that they don't have their final polishing and prescriptions, but they've all been fabricated from a blank into something that looks like a mirror, and then they go through testing at Marshall and get their prescriptions," Willoughby said.

The mirrors should be perfectly polished by September 2011, Morse said.

Northrop Grumman's spacecraft bus, which will house the observatory's housekeeping systems, is still awaiting its critical design review scheduled for May 2011. Willoughby said the bus was judged to be the least risky element in the program, so its development was postponed as officials focused on the more challenging instrument module and telescope apparatus.

The observatory passed its mission-level critical design review in April.

"JWST has come a long way," Morse said. "It's not a viewgraph mission. They are delivering engineering test units of almost all the subsystems, including all the instruments. And they're delivering flight hardware in many cases."