In a previous post (http://futureplanets.blogspot.com/2008/11/warring-views-on-msl.html) I printed excerpts from letters on the problems that MSL is facing. NASA is working to keep the launch of this mission on track for 2009. There will be budget hits -- still unspecified -- to other programs in NASA's science program. I am sure that NASA will structure the hits to minimize the overall pain, but there an expectation of pain to come.
Alan Stern, former NASA Associate Administrator for the Science Mission Directorate has written a reply to Dr. Garvin's reply to Stern's original letter. The reply is printed in the subscription only publication Space News. A core issue in all the letters is whether the Mars Science Laboratory represents a major increase in cost over what the community of scientists expected when they recommended it as a high priority.
NASA has several scientific bodies it uses to get recommendations on its scientific programs. Some, such as the Mars Exploration Program Analysis Group (MEPAG) are on-going. Some, such as the Decadal Survey met for a period at the beginning of the decade to review the overall program and then disbanded. Ultimately, however, NASA as a government agency, has the ultimate responsibility and authority to decide which advice to accept and which to reject. That said, my observation is that NASA listens to these bodies and tries within its budgets to follow the advice (and the sum of the recommendations always seem to call for more missions than there are dollars).
So what advice was NASA receiving regarding MSL in the early to mid parts of the decade? The Decadal Survey (2003 report), which looked at the entire planetary program, made MSL a priority but with the expectation that the cost would be ~$650M (a medium-sized mission). The goals of the mission were limited: "The MSL mission may be important, indeed essential, as a technology-demonstration precursor mission to MSR [Mars Sample Return], but the panel saw little science for MSL that cannot be done as well or better by [ohter] missions [such as Mars sample return]. The detailed examination and analysis of rock samples can be done far more capably in terrestrial laboratories (though admittedly MSL could perform simpler analyses of a larger and more dispersed set of samples than those that an MSR mission could return)... Since the panel’s task was to prioritize science missions and since it sees MSL largely as a technology demonstration mission, it has not included MSL among the prioritized missions."
MEPAG, on the other hand in a 2002-2003 report saw the MSL as a very capable science mission: "MSL will investigate the carbon chemistry in near-surface rocks and soil and provide a rigorous and definitive examination of their mineralogy as well as the extent to which they were formed or altered by water. Later missions in this Pathway will build upon this foundation of investigations and provide much more definitive tests for evidence of past life than will be possible from MSL and earlier landed missions. Advanced in situ instruments are expected to conduct biomolecular chemical analysis and higher spatial resolution examination of samples. The technology to acquire difficult-to-access samples, such as those buried several to tens of meters below the surface, will also be developed."
Both review bodies saw Mars as being the focus of at least one flagship class ($1-2B) missions in the period of ~2009-2020. The Decade Survey assumed it would be a Mars Sample Return (ball parked at $1.5B) and MEPAG saw it as MSL (and several less defined follow-on large missions). NASA decided that MSL was to be a highly capable science mission focused on exploring a site for past habitability and possible chemical signs of post life. The initial cost estimate for this mission after its detailed definition (after both the reports quoted above) was ~$1.5B. It's interesting to note that ESA's ExoMars rover was initially scoped as a ~650M euro mission that has grown to ~1.2B euro mission as it too focused on assessing habitability. (MSL now is probably ~$2.3B, but it is a much more capable rover with precision landing capability.)
NASA's science budget for planetary exploration is largely fixed with some variation from year to year. Fitting a highly capable MSL mission into that budget has to come at the cost of developing other missions to other targets. Is this a case of the Mars science community hijacking the planetary budget? Mars has been the recommended focus of NASA's planetary program for a long period. You can view NASA's planetary program as Mars-focused with funding for a limited number of other solar system missions, or as a balanced program badly out of balance as Mars dominates the budget. It probably depends on whether or not your scientific research focuses on Mars.
What follows are a portion Dr. Stern's views from his reply to Dr. Garvin apropos to the discussion above:
"Dr. Garvin claims that MSL’s original $650M cost, assigned by the NRC’s Planetary Decadal Survey when it ranked the mission high enough to proceed in 2003, was naïve. I agree here: any mildly experienced scientific program manager could have recognized this fact. Yet neither NASA headquarters, nor the implementing NASA center (JPL), nor the Mars community, came forward then, pointing out this obvious disconnect. As a result, the NRC’s community based Planetary Decadal Survey ranked MSL highly at an advertised cost level of $650M. Had they known its ultimate cost would be in excess of triple that, and the consequent damage that would result to the rest of the US planetary program to fund such increases in a fixed-budget environment, I believe it is doubtful that MSL would have received the same high ranking. NASA, JPL, and the Mars community abused the NRC’s high recommendation for MSL by “running away” with the mission’s ambitions and cost after it received a high ranking at the $650M level. When retailers practice such predatory practices, it is called “bait and switch.”
"MSL is a fine scientific mission, and I hope it works, for the fate of the US Mars program lies at its feet. But MSL has caused a great deal of damage to NASA’s broader planetary program: all that remains in hardware development are just one lunar and one outer planet mission; and by NASA’s own recent reckoning, even those two missions and portions of the planetary research and analysis programs which produce scientific discoveries are endangered now by MSL’s spiraling cost."