NASA Releases Full WFIRST Independent Review Report

The day before Thanksgiving, NASA released the full report of the WFIRST Independent External Technical-Management-Cost Review (WIETR). NASA earlier had indicated it would not release the full report until February 2018 when another report is due in response to the WIETR findings, but obviously changed its mind.  The full report amplifies and expands upon what was briefed to the National Academies’ Committee on Astronomy and Astrophysics (CAA) on October 25, 2017.

WFIRST, the Wide-Field Infrared Survey Telescope, was recommended by the National Academies in its most recent Decadal Survey for astronomy and astrophysics as the top priority for a large space-based telescope to follow the James Webb Space Telescope (JWST).  JWST has had a history of cost increases and schedule delays.  Its launch was most recently postponed from 2018 to 2019.  NASA hopes to avoid the same fate for WFIRST by trying to identify and solve problems now, while the project is still in formulation (Phase A).  The agency will soon decide if the project is ready to proceed to Phase B (preliminary design and technology development).

When the WIETR co-chairs, Peter Michelson and Orlando Figueroa, briefed the CAA in October, only part of the report was made public. (See our October 26 article for details.) Based on WIETR’s findings, NASA Science Mission Directorate Associate Administrator Thomas Zurbuchen directed Goddard Space Flight Center (GSFC), which manages the project, to submit a plan in February 2018 to descope WFIRST to reduce cost.  At that point, Zurbuchen said the full WIETR report would be released.  NASA did not state why it decided to release it now, but the astrophysics community undoubtedly wants to know the full story of what the committee recommended as soon as possible.

The CAA briefing focused on just one of the questions in the committee’s terms of reference — whether WFIRST’s scope and cost/schedule are adequately understood and aligned (Question B).  That answer was no.  WIETR found that the project’s cost has grown to $3.9-4.2 billion compared to the $3.2 billion estimate at the time it entered Phase A or the $3.6 billion currently estimated by project management.

The full WIETR report provides many additional charts on that issue as well as addressing three other questions that were only touched upon in the CAA briefing: Question A, whether the technical requirements are understood and reasonable; Question C, whether the management processes in place are adequate; and Question D, whether the benefits of the coronagraph to NASA objectives are commensurate with the cost and cost risk of development.  The full report also contains the committee’s recommendations and options for addressing them.

As recommended by the Decadal Survey, WFIRST was a modest mission for a large “flagship” telescope ($1.6 billion in 2010 dollars).  NASA has made significant changes since then, however, the most controversial of which is the addition of the coronagraph.  A coronagraph blocks the light from a star so nearby objects, like planets, are easier to detect. NASA has flown spacecraft with coronagraphs in the past, but much higher resolution is needed to see planets around other stars in the galaxy. On WFIRST,  the coronagraph is only a technology demonstration, with no science requirements.  Among the questions is the wisdom of flying a technology demonstration on a flagship mission and whether the associated cost and schedule risk is justified.

Two reviews by the Academies in 2014 and 2016 warned of the impact of adding the coronagraph.  It was the second of those studies that recommended NASA conduct its own review, which became WIETR. Like those reports, WIETR makes clear that the coronagraph is driving cost — adding about $400 million.  WIETR’s answer to whether the benefits are worth the costs is ambivalent, at best.  The long term benefits of coronagraph development are “indisputable,” WIETR concluded, but “there is a risk that conflicts” may emerge because it is only a technology demonstration and that “can be misleading for science teams and yield unrealistic expectations from the science community.” WIETR also found that the current budget profile is “inconsistent” with the coronagraph’s development needs.

The full report identifies options for dealing with that and other issues, but its bottom line, as expressed to the CAA, is that “as designed, the risks to the primary mission of WFIRST are significant and therefore the mission is not executable without adjustments and/or additional resources.”