Friday, August 20, 2010

The Not-So-Great Compromise: Robotic Precursor Missions

In spite of the view held in some circles that "all we need is a good map", robotic precursor missions are essential if we are going to rocky destinations like the Moon, NEOs, Mars moons, or Mars, especially if we want to do so in an affordable, safe, and productive manner. We certainly do need a good map, and in fact we need many kinds of good maps. We also need much more than maps from robotic precursor missions. Example jobs for robotic precursor missions include assessing hazards to astronauts, measuring local resources, practicing use of those resources, performing various other technology demonstration tests, and evaluating potential locations for astronauts.

Let's compare the Administration and Senate Authorization proposals in terms of robotic precursor missions. Figures are in millions of dollars:


If we extend the Authorization Committee's pattern to FY2015, we see that there is a 6-fold difference: about $3,000M in the Administration budget compared to $500M in the Senate budget.


NASA presented some early ideas on what they would like to do with a well-funded robotic precursor mission line. In May, during an exploration workshop, the FY 2011 Exploration Precursor Robotic Missions (xPRM) Point of Departure Plans (PDF) included:

  • a series of main robotic precursor missions ($500M - $800M each)
  • a series of small "Scout" missions ($100M - $200M each)
  • development of instruments to be flown on science missions
  • data systems, research, analysis, and sensor technology development
The initial set of proposed missions included:

FY----Large Mission----Scout----Hosted Instrument
2014..NEO Rendezvous...yes......yes
2015..Lunar Lander..............yes
2016..Mars Orbiter.....yes......yes
2018..Mars Lander......yes......yes
2019..NEO Rendezvous............yes

This would have strained the available $3B budget from 2011-2015, but if some funding from later years is counted, perhaps it could be done. Probably the most serious flaw in this series of missions is that it emphasizes Mars too much, considering that Mars is such a distant goal in NASA's exploration schedule. NASA needs to focus much more on nearer-term destinations if it wants to succeed in the earlier steps on the way to Mars. We need multiple robotic precursor missions for our next rocky destination, whether that destination is the lunar surface as described in the Flexible Path to the Moon, or NEOs as described in the Augustine Flexible Path to Mars.

A more recent presentation shows that NASA's evolving robotic precursor plans are addressing both the funding and the focus problems I just mentioned. In the Explore NEOs Objectives Workshop (Explore NOW), the robotic precursor plans presented in the updated version of Exploration Precursor Robotic Missions (xPRM) Point of Departure Plans (PDF) include:

FY----Large Mission----Scout----Hosted Instrument
2015..Lunar Lander.....yes......yes
2016............................yes 2017..NEO..............yes......yes

One of the large Mars missions has been replaced by a NEO Scout. This makes funding the line more achievable (although still a stretch) with $3B, especially if we can count some funds in later years. In addition, the NEO missions are done sooner, allowing the results from these missions to inform astronaut NEO missions. Finally, with 3 NEO missions instead of 2 (1 of which was late in the original plan), there is a serious enough focus on NEOs to really be able to help the astronaut missions to NEOs succeed. On the Flexible Path to Mars, later robotic precursor missions could focus on the Moon or Mars and its moons, depending on what branch of that path is taken.

Ideas for the 2 main NEO missions include a NEO Telescopic Survey to identify a better selection of NEOs reachable on early deep space astronaut missions, or a NEO Rendezvous mission that could focus on a single NEO or give more high-level information about multiple NEOs using multiple small spacecraft. The 2 larger NEO missions are anticipated to cost in the $640M-$840M range through their complete life cycle.

Now let's go back to the Senate budget. Assuming their FY2011-2013 trend is kept, that budget gives $500M through FY2015. Another Senate committee's version of the budget only gives $44M in FY2011, so it would only have $444M through FY2015.

There is not enough money to run a single robotic precursor mission in the $640M-$840M class NASA envisions with the Senate budget even if that budget is projected through FY2015.

The Senate limits the robotic precursor line to 1 or 2 very small missions, 1 or 2 instruments, and supporting work like research and data systems. It acknowledges this limitation by giving the funding line the title "Robotic Precursor Instruments and Low-Cost Missions". I frequently find myself in favor of a strong emphasis on small missions, but there really needs to be a healthy mixture of smaller and larger missions.

Based on the lack of robotic precursor mission funding, my conclusion is that the Senate bills for all intents and purposes rule out any aspirations NASA might have for astronauts reaching rocky world destinations like the Moon, NEOs, Mars moons, and Mars.

Now we come to the question of compromise. Is there a viable compromise between the Administration and Senate proposals that achieves important objectives? I think there is if the Senate gives some ground on Heavy Lift rocket and Orion funding. Over the next few posts, I'll use an example of shifting a billion dollars or so per year from these lines to robotic precursors, exploration technology, and commercial crew. This would still give the Senate what it wants: funding on a massive scale for a Shuttle-derived rocket and Orion spacecraft, eventually flying astronaut missions beyond LEO. It would also allow efforts like the robotic precursor line to function, even if not as spectacularly as planned in the original FY2011 budget proposal. In my examples, I'll make a crude breakdown (ignoring details like funding profiles to match realistic project work levels over time) for the hypothetical shifted $1B/year by dividing it as follows:
  • 25% ($250M/year on average) for Robotic Precursor Missions
  • 25% ($250M/year on average) for Exploration Technology Development and Demonstrations
  • 50% ($500M/year on average) for Commercial Crew
In my examples, these amounts would be added to the original Senate plans for these 3 funding lines, thus representing a compromise between the Senate and Administration budgets.

With this budget compromise, Robotic Precursor Missions would see a dramatic increase from $500M to $1,750M from FY2011-FY2015. That doesn't come close to the Administration proposal, but it's a compromise. Can the Robotic Precursor Mission line do useful work with this amount of money? I think so. Unfortunately, that level of funding would probably require NASA to eliminate most or all robotic precursor missions to all destinations beyond their first expected destination for astronauts. If the first destination is NEOs, the plan might be cut back to something like this:

FY----Large Mission----Scout----Hosted Instrument

A similar view might hold for lunar robotic precursor missions if we choose to go to the lunar surface as the first rocky destination instead of NEOs.

With missions with life cycle costs from $640M-$840M, we could squeeze a couple large missions and a couple Scouts, as long as we stay much closer to the $640M side than the $840M side for the main missions. We might have to trim some capabilities off of those missions to make sure that happens, or we might have to turn one of the bigger missions into a Scout or 2. Either way, we go from the Senate's completely non-functional Robotic Precursor plan to one that is limited, but that can help chart the course for astronaut missions.

Would this be enough for safe, cost-effective, and productive astronaut missions? I suspect it would require additional help from NASA's Planetary Science community. If NEOs are the first destination, SMD might need to set up a NEO-specific funding line similar to the existing Lunar and Mars ones. With cooperation with NASA SMD, commercial space, non-profits, and international missions, we might even be able to form a quite capable, if focused, Robotic Precursor line.

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