An independent review of the James Webb Space Telescope (JWST), a mammoth space-borne infrared observatory that should greatly surpass even the venerable Hubble Space Telescope in observing power, has revealed that the telescope will cost about $1.4 billion more than had been thought. And the telescope is likely to launch more than a year later than had been planned, according to the report, which was made public November 10.

The seven-member review panel, convened at the request of Sen. Barbara Mikulski (D–Md.), concluded that the complex observatory, which features a foldable, segmented mirror and a multilayer sunshade the size of a tennis court, is on sound technical footing. But the "badly flawed" budget presented to NASA Headquarters in 2008 by project staff did not include enough total funds, and the reserve funds that were added in to account for surprise costs were neither sufficient nor phased in during the years they would actually be needed.

The panel, chaired by John Casani of the NASA Jet Propulsion Laboratory, found fault both with the authors of that 2008 budget and with NASA Headquarters for not identifying the budget's flaws. "From a dollar standpoint it was just insufficient to carry out the work," Casani said in a November 10 teleconference about the report. "This is a very large, complex project, and to estimate to any degree of precision something that has never been done before is a tough job," he added later in the teleconference.

Casani's group, which included representatives from academia and industry, sought to determine the minimum cost and earliest launch date for JWST. The figures they came up with were a cost of $6.5 billion, up from a prior estimated cost of $5.1 billion, and a launch date of no sooner than September 2015. The telescope had previously been targeted for a June 2014 launch.

But both estimates, Casani noted, "would require funding in fiscal years 2011 and 2012 that would be substantially over what is in the president's request." In other words, political and economic realities may cause further slips of the launch date as well as additional cost increases. The project would need more than $250 million above what President Obama had requested for it in both 2011 and 2012 to meet the panel's targets.

"We're going to look at what we can do" to add money to JWST in the coming years, said NASA Associate Administrator Christopher Scolese, a top official at agency headquarters. "I think it's fair to say I doubt that we're going to find $200 million." Scolese said that NASA was heeding the suggestions made in the report, which included elevating JWST to a more visible program that reports directly to him. "We have some recommendations that we have to go off and deal with, and we will," he said.

Even though the project continues to eat up a large portion of NASA's astrophysics budget, it carries a stamp of approval from the astronomy community. The observatory was endorsed as the top-ranked large-scale project in the 2000 decadal survey, an influential National Research Council report that helps set funding priorities for the coming years. "James Webb is a hugely more powerful facility than Hubble, 100 times at least," said Garth Illingworth, an astronomer at the University of California Observatories who sat on the inquiry panel. "The science just underpins so much of what we're looking to do in the future."

And even with the harsh realities revealed by the new report, Scolese said that JWST's value should carry the day. "We believe that JWST will be a valuable tool for the astronomers; it will improve and enhance our view of the universe," he said. "We believe that we can bring forward a credible plan, and that with a credible plan it will be accepted."