Wednesday, March 25, 2009

Decadal Survey Taking Shape


The next Decadal Survey for planetary missions is taking shape. I am encourage by what I'm reading (but more on that in the editorial notes).

Steven Squyres, at Cornell University and PI for the MER Mars Rover, has been named chair and Larry Soderblom, from the USGS Astrogeology Team in Flagstaff, Arizona, has been named vice-chair. Over the next two and a half years, the Decadal Survey will prepare a report that:

  • An "inventory of top-level scientific questions that should guide flight programs and supporting research programs"
  • Recommend the "optimum balance among small, medium, and large missions"
  • Create a "prioritized list of major flight investigations in the New Frontiers and larger classes recommended for initiation over the decade 2011-2020'"
  • Prepare "a prioritized list of major flight investigations in the New Frontiers and larger classes recommended for initiation over the decade 2011-2020"
  • Create a "list of important science goals which could be achieved by small spacecraft (Discovery and Scout class) missions"

The process will be organized by panels focused on different classes of solar system bodies: inner planets, Mars, outer planets, outer planet satellites, and primitive bodies (asteroids and comets). These panels will take input from established panels (such as MEPAG, VEXAG, etc.), from town halls, from ad hoc groups of scientists with a shared interests, and individuals (with a specific note including input from students).

The following points from the latest Decadal Survey emphasize key points that will be different than the process last time:

"Compared to previous decadal surveys, this one will place much greater emphasison evaluation of the technical maturity and probable costs of candidate missions.
  • The Panels and the Steering Committee will include members who are expert in engineering, project management, and cost estimation.
  • Resources are available to do moderate-fidelity (and conservative!) cost estimates for a limited number of high-priority candidate missions.
  • The objective is to produce a realistic (i.e., not heavily over-subscribed) set of candidate missions for NASA to carry out in the coming decade."
A key criticism of the last planetary (and astronomy) Decadal Survey was that the list of priority missions had wildly optimistic (i.e., low) cost estimates. As a result, list of missions was unaffordable.

Another key aspect of the Decadal Survey will be that "Mars missions will be considered on an equal basis with all other missions. No 'set aside'for Mars exploration will be assumed a priori."

Editorial thoughts: I am encouraged by the early direction the Decadal Survey is taking. NASA and the planetary community have clearly learned from the mistakes of the last Survey, which nevertheless provided the roadmap for the planetary exploration program of the past decade. It turned out that only a portion of the program could be implemented within the available budget. (And a more capable and expensive Mars Science Laboratory was substituted for the one prioritized by the Survey.)

I expect that the Survey will still prioritize more missions than can be afforded. In my days of working budget processes, you always asked for more than you expected. What I will be looking for is a clear set of priorities both among missions and among classes of missions. If that is clear, then the highest priorities should be funded (assuming similar budgets for the next decade).

I would also be surprised if Mars does not remain a high priority and receives a good portion of the proposed resources. Looking at various mission proposals, Mars is simply cheaper to explore both because it is close and it has a relatively benign environment. A mission similar to the Jupiter Europa Orbiter (~$3B), for example, would probably be a half to a third that much at Mars.

Here are some predictions (I'll try to remember to score them in two and a half years).
  • I expect that Mars will get around one-third of the mission development funds, Jupiter Europa another third, and New Frontiers and Discovery missions will receive the remaining third.
  • The tough discussion will be between preparing for a Venus or Titan Flagship mission the following decade. Both deserve investigation, but if NASA can afford one Flagship mission in the 2020s (as it has in the 2000's and 2010's), only one is likely to fly. My guess is that the Survey will call for early development for both to enable a competition between them in about a decade.
  • The other tough debate will be around the list of priorities for the Discovery and New Frontiers missions. The priorities set in the last Survey have guided the selection of these mssions in the past decade. Because these missions are led by individual researchers who have specific missions they want to see fly, the desire to get particular goals prioritized will be strong.

I welcome your predictions in the comments.

Resources:

Decadal Survey home page

Latest presentation on process to be followed

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