NASA’s ‘Large Strategic’ Science Missions Under the Microscope

Earlier this year, the National Academies of Sciences, Engineering, and Medicine established a committee to study the significance of “large strategic” missions within NASA’s science mission portfolio. Addressing the committee’s second meeting last week, John Grunsfeld—who led NASA’s Science Mission Directorate (SMD) from 2012 until his retirement this year—explained the rationale behind the study.

According to Grunsfeld, by December 2013 NASA Administrator Charles Bolden had become publicly disenchanted with the expense and political volatility of what the agency was then calling “flagship” science missions. In response, Grunsfeld recast flagships as “large strategic” missions, highlighting their critical role in fulfilling SMD’s science strategy , which integrates the work of the directorate’s four divisions: Planetary Science, Astrophysics, Earth Science, and Heliophysics. This emphasis, along with ongoing congressional support, opened the door to new large strategic missions such as Mars 2020, the Wide Field Infrared Survey Telescope, and a projected mission to Europa.

Even still, in Grunsfeld’s view, the significance of large strategic missions remains poorly understood, making it unduly difficult to gain approval for them. For this reason, he recalled, he initiated NASA’s request for the National Academies study prior to his departure from the agency.

The committee will not conclude its study until next summer. The immediate purpose of last week’s meeting was to survey issues to be addressed in the coming months. In addition to Grunsfeld, the committee heard from his successor Thomas Zurbuchen, senior SMD division leaders, and former and current congressional staff members. Together, these speakers described the various policy questions that NASA confronts in proposing and designing large strategic missions.

NASA directing attention to its large-mission budgeting practices

The NASA officials at the meeting explained that the threshold defining “large” missions varies by division, but that they generally cost more than $1 billion. All large missions must be justified as strategic, but not all strategic missions are large. Notably, Michael Freilich, NASA’s Earth Science director, emphasized that his division no longer develops large missions because, for its purposes, it is operationally preferable to assemble a “strategic portfolio” of medium and small-scale missions. NASA administers all “strategic” missions directly, and strategic missions are distinguished from “competed” missions, which are proposed and led by extramural researchers.

The officials worked to dispel the notion that large strategic missions crowd out smaller missions, with the James Webb Space Telescope (JWST) taken as a key case in point. That mission had been subject to delays and cost overruns, leading NASA in 2011 to rebaseline its life-cycle cost from almost $5 billion to over $8.8 billion and to push its launch date back from 2014 to 2018. Paul Hertz, director of NASA’s Astrophysics Division, emphasized that it was a declining division budget and not JWST that had been responsible for decreasing funding for other division projects after 2005. Grunsfeld asserted that, had JWST been cancelled, its funding would likely have been diverted from Astrophysics altogether, resulting in a much-diminished division.

Some of the NASA speakers noted that the agency works to confine cost overruns on large strategic projects by delaying their schedules rather than diverting funds from other projects. However, they also highlighted NASA’s success since 2011 in budget management, keeping NASA-administered missions, in aggregate, within one percent of their projected development costs. The officials explained that this success stemmed from policies implemented before 2011, which better respect missions’ budget reserves as a communal tool for mitigating the risk of cost overruns. Past practice had been to try to use all available budget, including reserves, to maximize scientific output. (Additional information can be found on pages 150 to 154 of NASA’s Fiscal Year 2015 Agency Financial Report .)

During the meeting, the question arose several times of whether large missions can become “too big to fail,” an evocative shorthand for the idea that sunk costs in large, high-yield science projects always tend to justify additional expenditure. The former and current congressional staff members at the meeting suggested that current congressional goodwill toward NASA could turn sour if a project appeared to be venturing beyond the reach of congressional oversight. However, Jeff Bingham, who formerly worked on NASA issues for the Senate Commerce, Science, and Transportation Committee, also urged NASA not to let Congress forget the role that lawmakers sometimes play in causing cost overruns.

[Update: Via email, Paul Hertz has clarified that discussion of large strategic missions becoming “too big to fail” specifically concerned the possibility that, if a large mission were cancelled, “the damage to NASA’s science output with the loss of that mission’s science plus the reduction in large mission cadence would cause unacceptable damage to the science program.”]

Committee to assess ways large missions achieve various goals

Much of the discussion at the committee meeting concerned what role large strategic missions play in keeping NASA’s science mission portfolio properly balanced. Participants recognized that portfolio balance between differently sized missions and between strategic and competed missions is important not only to maximizing scientific productivity but also to other, longer-term goals.

One such long-term goal is the development of instrumentation and other technologies that permit new generations of missions to press forward major advances in scientific knowledge. While the NASA officials highlighted differences in how each SMD division handles technological development, there was a consensus that large strategic missions can both take advantage of and foster vanguard technologies in ways that smaller missions do not. However, one of the lessons learned from the JWST experience is that technologies should be fully mature at an early stage in the mission development process, limiting the technological development that can take place closer to launch.

Another long-term goal is sustaining the broader scientific community. Participants recognized that maintaining a consistent cadence in large missions is essential to retaining expertise that is unique to them. Furthermore, Grunsfeld observed that American preeminence in some large-mission capabilities had now diffused to other countries, which had opened up new opportunities for international collaboration.

At the same time, some committee members expressed concerns about the teams running large missions being limited to a relatively closed group of highly experienced investigators. On this subject, the NASA officials pointed to initiatives such as the agency’s Participating Scientist Programs, which give visiting researchers opportunities to join mission teams. They also noted that some large strategic missions produce expansive sets of open, general-purpose observations and data, and thereby play an outsized role in sustaining the work of large numbers of researchers at all experience levels.

One problem implicit in all portfolio choices is how to measure the productivity of any particular mission on a “science per dollar” basis. In their presentations, the NASA officials used publication output as a proxy for scientific production, but they and the committee members had animated discussions about how such metrics fail to capture less tangible benefits, such as fostering novel collaborations, that strategic missions can realize. Participants noted that this issue also came up in another recent National Academies study dedicated to mission extensions (see FYI #109 ). They observed that it is likely to remain an important—and open—question for the foreseeable future.

There is no certainty as to which points discussed during the meeting will and will not be considered in the committee’s final report, or what recommendations the committee will make. Further discussion will take place at its next meeting in Irvine, California this December.

Note: Article updated 10/14/16 to clarify the nature of the idea that large strategic science missions can become “too big to fail.”