Vision and Voyages for Planetary Science in the - Solar System ...

to acceptable levels. For NASA in the coming decade, this principle means that MAX-C should acquire
adequately characterized samples at a cost of no more than $2.5 billion. And because both the NASA and
ESA elements of the mission will be delivered to the same landing site, it is important to make their
descoped science as complementary as possible.
As described below, the two subsequent missions in the Mars Sample Return campaign would
take place after 2022. The timing is flexible; as described in Chapter 6, the MAX-C sample cache will
remain scientifically viable for at least 20 years. The committee has therefore taken the unusual step of
recommending a plan for the coming decade that also has significant budget implications for one or even
two decades beyond. The committee does this intentionally and explicitly, with the realization that
important multi-decade efforts like Mars Sample Return can only come about if such recommendations
are made and followed. As noted above, the committee’s recommendation is predicated on the
assumption that collaboration with ESA will be maintained throughout the length of the Mars Sample
Return campaign, offsetting some of NASA’s costs. It is also important for the science return from the
combined MAX-C and ExoMars missions to be significant even if the samples are never returned. Given
the ambitious goals of MAX-C and ExoMars, this should be possible even if major descopes are
necessary. The committee also stresses that significant sample-return technology investment in the
decade 2013-2022 will be necessary, as discussed in more detail below.
A final point regarding MAX-C is that its success depends in part on the success of the MSL EDL
system. If that system functions properly in 2012, then a $2.5 billion MAX-C mission should go forward
for launch in 2018. If it fails, however, then NASA will have to reconsider the priority and schedule for
MAX-C. If the cause of failure can be determined and appropriate and affordable changes can be made in
time to preserve a 2018 launch, then MAX-C can continue on schedule. However, if uncertainties remain
or if the necessary changes cannot be made by 2018, then MAX-C should slip in priority and schedule
relative to other large-class missions.
The second highest priority Flagship mission for the decade 2013-2022 is JEO. However, its
cost as currently designed is so high that both a decrease in mission scope and an increase in
NASA’s planetary budget are necessary to make it affordable.
The Europa Geophysical Explorer, from which the JEO concept is derived, was the one Flagship
mission recommended in the previous planetary decadal survey. The scientific case for this mission was
compelling then, and it remains compelling now. There is strong evidence that Europa has an ocean of
liquid water beneath its icy crust. Because of this ocean’s potential suitability for life, Europa is one of
the most important targets in all of planetary science. As its name implies, JEO will also do other
important science in the Jupiter system, including study of other moons, and of the planet itself. Like
MAX-C, JEO directly addresses all three of the crosscutting themes of Chapter 3, and is, in particular,
central to Planetary Habitats. Substantial technology work has been done on JEO over the past decade,
with the result that NASA is much more capable of accomplishing this mission than was the case 10 years
ago.
The difficulty in achieving JEO is its cost. The projected cost of the mission as currently
designed is $4.7 billion FY2015. If JEO were to be funded at this level within the currently projected
NASA planetary budget it would lead to an unacceptable programmatic imbalance, eliminating too many
other important missions. Therefore, while the committee recommends JEO as the second highest priority
Flagship mission, close behind MAX-C, it should fly in the decade 2013-2022 only if changes to both
the mission and the NASA planetary budget make it affordable without eliminating any other
recommended missions. These changes are likely to involve both a reduction in mission scope and a
formal budgetary new start for JEO that is accompanied by an increase in the NASA planetary budget.
It is clearly crucial to keep the budget increase required to enable JEO as small as possible.
Because of the maturity of the current JEO mission concept, the committee did not attempt to redesign the
mission for lower cost. However, such a redesign is essential for this important mission to be viable.
Possible pathways to lower cost include use of a larger launch vehicle that would reduce cost risk by
shortening and simplifying the mission design, and a significant reduction in the science payload. Other
possible descopes were listed in section 4.1.5 of the 2008 JEO mission study final report. 14 NASA
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