Asastronomers gathered at the Space Telescope Science Institute here for threedays of talks about the big missions they would like to tackle from 2020onward, NASA's astrophysics chief warned them not to get stars in their eyes asthey envision future budgets.
"I wouldencourage folks to think about the future optimistically, but we do have tolive within realistic funding levels," Jon Morse, the director of NASA'sastrophysics division, said Nov. 14 at the Astrophysics 2020 meeting.
NASAcurrently spends $1.5 billion, or about 9 percent of its total budget, onastronomy and astrophysics. But as the JamesWebb Space Telescope, the division's largest project, begins to come downoff its peak funding years and five smaller spacecraft leave the launch padover the course of the next two years, NASA's current projections show thedivision's annual budget dipping to below $1.3 billion before starting toincrease again about 2012.
"I wantto make sure the community is fired up because astrophysics is a tremendousplace to be working right now because of the discovery potential," Morsesaid. "Nevertheless, we have to live within our means."
Morse saidthe community should plan on only inflationary increases for astrophysics andastronomy in the decade ahead. Astronomers risk disappointment, he said, ifthey assume their share of the NASA budget will grow much beyond what it istoday.
2020 mightseem like a long way off for a space agency that writes and rewrites a newfive-year budget plan every year. But the investments needed to enable the bigflagship-class missions, such as the 20-meter aperture telescopes someastronomers were talking about here, will have to be made in the decadeimmediately ahead.
Morse saidNASA's future budget decisions will be guided by the recommendations of thenext so-called decadal survey for astrophysics and astronomy, a 10-year plan tobe developed by the National Academy of Sciences. Many of the scientistsattending the meeting here will have a hand in shaping those recommendations.
The nextdecadal survey, which is expected to get under way in late 2009, will not onlyset the mission priorities for 2010-2020, but also will recommend the otherinvestments NASA needs to make during that period to lay the foundation for themissions that will take place in the following decade.
If the panelthe National Academy of Sciences charters to conduct the decadal survey assumesa budget trajectory "much more optimistic than anything like inflation,then I think we are going to have trouble delivering on the portfolio thecommunity would like," Morse said.
For anexample of the consequences of a mismatch between priorities and budget,scientists need look no further than the 2000 decadal survey, Morse said.
"TheAcademy could come back and say, 'OK NASA, what's your grade this decade formaking progress on the decadal survey? How many missions did you launch thatwere on our list?' The answer? One. GLAST," Morse said, referring to theGamma-ray Large Area Space Telescope, which is slated to launch in early 2008from Florida aboard a Delta 2 rocket.
In all, thelast decadal survey recommended nine space-based astronomy missions for NASA totackle between 2000 and 2010, including the Solar Dynamics Observatory, an $800million mission funded by NASA's heliophysics division, that also is slated tolaunch in 2008.
But besidesGLAST and the SolarDynamics Observatory, the only other mission from the 2000 decadal surveyanywhere close to being accomplished is the James Webb Space Telescope (JWST),slated for launch in 2013.
Morse saidthe 2000 decadal survey did a commendable job of planning and prioritizing thescience. Where it fell short, he said, was in estimating what the missionswould actually cost. NASA, he said, shares the blame.
"What wecollectively got wrong was the cost, and this has slammed shut the progress we'vebeen able to make because the cost were much higher in reality," Morsesaid.
The decadalsurvey put the total price tag for JWST, Constellation-X, Terrestrial PlanetFinder and the Single Aperture Far-infrared Observatory at $2.1 billion.
JWST alone – thesurvey's highest priority – now is expected to cost $4.5 billion by the time itcompletes its nominal five-year mission around 2018. Constellation-X, an X-rayobservatory designed to watch matter get sucked into super massive black holes,would cost around $2 billion should NASA decides to tackle it, according to anew estimate prepared for the National Academy earlier this year.
While some ofthe differences between estimated and actual cost can be explained by NASA'stransition in 2004 to full cost accounting, Morse said the earlier estimatesstill were dramatically off base – something the agency learned as it got goingon ambitious projects like TerrestrialPlanet Finder only to shove them off into the indefinite future.
Not wantingto repeat the mistakes of the past, NASA and the National Academy are planningto inject more rigorous cost estimating procedures into the next decadalsurvey, Morse said, with NASA planning to foot the bill for independentassessments.
NASA also isfunding some advance work in the form of mission concept studies that will helpscientists and their corporate sponsors flesh out their ideas for medium- andlarge-class missions ahead of the next decadal survey. Proposals are due inNov. 20 with awards expected early next year.
Better costestimates alone will not guarantee that NASA can deliver on the recommendationsof the next decadal survey, Morse said.
"We needto make sure we have better management and that mean's controlling cost,"he said, citing the Kepler space telescope of an example where NASA's ScienceMission Directorate stepped in this year to rein in costs on the over budgetmission, making management changes, cutting expenses and forcing concessionsfrom the contractor.
"We aregoing to try to make sure we exercise cost control because we want to value thefuture [mission] queue and not just throw tons of unanticipated resources intothe projects that are in plan," Morse said. "It just bringseverything to a screeching halt."
WhetherMorse's audience got the message remains to be seen. One astronomer questionedwhether the community should just accept that their share of the budget willremain static, or whether they should fight for a bigger piece of the pie.
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