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6
NASA Program Implementation
THE NASA HELIOPHYSICS CORE PROGRAM
The systems approach for the study of the coupled Sun-heliosphere-Earth system that is
advocated in this report requires flight opportunities that can provide observations of phenomena
throughout the domain as well as adequate support of research and analysis activities to ensure that the
full potential of the data are realized. With current projections showing at best level funding for solar and
space physics over the coming decade, the survey committee was challenged to prescribe a program that
would effectively “do more with less.” Among the key considerations in this effort are the appropriate
mix and repeat-cycle (cadence) of small-, medium-, and large-class missions, and matching these efforts
with a robust program of research and analysis and theory and modeling activities that will exploit,
complement, add value, and, in effect, extend experimental observations. Further, in order to take
advantage of future opportunities, there is an evident need to develop a well-trained workforce
The heliophysics core program that should be preserved and implemented includes the following
elements, in order of priority:
1. Completion of the implementation of the NASA missions that are currently selected, with
commitment to maintaining cost and schedule commitments. This includes RBSP, MMS,
Solar Probe Plus, Solar Orbiter, along with IRIS and other already selected Explorers.
2. Initiation of the DRIVE program as an augmentation to the existing enabling research
program. The DRIVE components provide for operation and exploitation of the
Heliophysics System Observatory for effective research programs. The community must be
equipped to take advantage of new innovative platforms.
3. Execution of a robust Explorer program with an adequate launch rate, including missions
of opportunity (MOOs). The cadence should be accelerated to accomplish the important
science goals that do not require larger missions and to provide access to space for all parts
of the discipline.
4. Launch of strategic missions in the reinvigorated STP line and in the LWS line to
accomplish the committee’s highest-priority science objectives. This includes first the
notional IMAP investigation and then DYNAMIC and MEDICI in the STP program and
GDC as the next larger-class LWS mission.
Figure 6.1 shows a proposed implementation of the core program, in which each of the assets
required to achieve the goals of the solar and space physics program have their proper cadence, within a
budget profile that should be attainable. The recommended program addresses in a cost effective manner
many of the most important and interesting science objectives, but the anticipated budget significantly
constrains what can be accomplished. Built on top of the existing research foundation, the core program
recommended here ensures that a proper distribution of resources is achieved. In particular, it restores a
balance between small, medium, and large missions.
Figure 6.2 illustrates how, in the past decade, the number of large missions has increased at the
expense of medium and small missions. By implementing the committee’s proposed program, the
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balance between mission size and enabling research is restored. As shown in Figure 6.3, at the beginning
of the 2013-2024 decade large missions from both the LWS and STP lines dominate the budget. By the
end of the decade, a balance between large, mid-sized, Explorer and enabling assets (baseline research
plus DRIVE) has been achieved.
The phasing that leads to this rebalance is implemented based on the priorities accorded to the
elements of the core program. During the early part of the decade, when there is very little flexibility in
the NASA heliophysics program, the focus is on the completion of the implementation of existing
missions, as well as on maintaining the baseline level of enabling research programs and Explorers. The
first new recommendations of this survey to be acted upon pertain to DRIVE. Early implementation of
DRIVE ensures the fastest possible return on new investments for the decade (Figure 6.4).
The next priority element is the Explorer augmentation, and this is also acted upon as early in the
decade as possible. Explorer missions are cost-effective means of strategically pursuing new and exciting
science. The recommended augmentation of the Explorer line allows for a restored MIDEX line to be
deployed in alternation with SMEX missions at a 2- to 3-year cadence and for regular selection of
Missions of Opportunity
The committee’s highest ranked STP and LWS missions, IMAP and GDC, are implemented next,
exploring the outer heliosphere and near-Earth space respectively. The minimum recommended cadence
for the STP missions is 4 years, so IMAP, as a moderate-sized mission, could launch in 2021 and be
followed by DYNAMIC and MEDICI, the next highest ranked STP science targets (FIGURE 6.5). The
recommended cadence for LWS is 6 years (Figure 6.6), so only GDC could begin this decade. Moreover,
launching GDC even as early as 2024, as shown in Figure 6.1, would require an increase in the
heliophysics budget, beyond a simple extension of the current budget. The increase would permit the
timely execution of a major mission in coordination with related STP missions. However, if the required
increase is not possible, it is appropriate to delay both the start and launch date of GDC.
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FIGURE 6.1 Heliophysics budget and program plan by year and category from 2013 to 2024. The solid
black line indicates the funding level from 2013 to 2022 provided to the committee by NASA as the
baseline for budget planning, and the dashed black line extrapolates the budget forward to 2024. After
2017 the amount increases with a nominal 2 percent inflationary factor. Through 2016 the program
content is tightly constrained by budgetary limits and fully committed for executing existing program
elements. The red dashed “Enabling Budget” line includes a modest increase from the baseline budget
starting in 2017, allowing implementation of the survey-recommended program at a more efficient
cadence that better meets scientific and societal needs and improves optimization of the mix of small and
large missions. From 2017 to 2024 the Enabling Budget grows at 1.5 percent above inflation. (Note that
the 2024 Enabling Budget is equivalent to growth at a rate just 0.50 percent above inflation from 2009.)
GDC, the next large mission of the LWS program after SPP, rises above the baseline curve in order to
achieve a more efficient spending profile, as well as to achieve deployment in time for the next solar
maximum in 2024. NOTE: LWS refers to missions in the Living With a Star line and STP refers to
missions in the Solar-Terrestrial Probes line.
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FIGURE 6.2 NASA mission sequence since 1990 by launch year and mission class. The strength of the
heliophysics program over the past two decades has been the regular cadence of missions in a variety of
sizes. It can be seen that the 1990 and 2000 decades each had 13 missions with the Medium and Explorer
Class categories having 9 missions in each decade. A trend toward a loss of balance can be seen in the
2010 decade where the mission complement has tipped toward fewer missions with a bias toward the
Large category.
A key objective for the next survey interval is to restore the number of Medium and Explorer class
missions such that, in combination with competitively selected Instrument Opportunities on hosted
payloads (MOOs), a higher cadence can be achieved that is capable of maintaining the vitality of the
science disciplines. As discussed in the text and described in Figure 6.1, funding constraints affect the
restoration and rebalance of the programs such that realization of the strategy cannot begin until after
2017.
Missions denoted by an asterisk (*) demonstrate the importance of international collaborations where
the heliophysics community has a long, active and very fruitful mission history. Open boxes indicated
missions that that are in development, or are planned, but have not yet flown.
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FIGURE 6.3 Effects of strategic rebalancing. These pie charts illustrate the evolution of program
balance among four core program elements as the survey-recommended plan is implemented over the
Survey Interval, 2013-2002, plus 2 years. The charts reflect that much of the NASA heliophysics budget
from 2013-2017 is already “locked in.” The year 2017 is effectively the start to an “enabling trajectory.”
An important result apparent in 2017 is the effect of implementing the DRIVE initiative and the
restructured Explorer program. It can be seen that the sum of Research + DRIVE and Explorers (R+D+E)
increases from approximately 37% to the intended value of 50% of the total program budget.
The year 2022 represents the endpoint the Survey Interval and demonstrates that the overall
rebalancing of the program has occurred with the maintenance of the 50% R+D+E funding but also a
sustainable division between the STP and LWS program with the remaining 50% of the budget. The year
2024 represents the planned endpoint of the rebalancing initiative as well as the legacy profile for the next
survey. An important legacy result is how the program stably maintains the balance moving forward from
2022. Note that the 2022 and 2024 budgets are represented by the “Enabling Trajectory” budget and do
not include the GDC bump which is considered a plus-up from the base program.
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FIGURE 6.4 NASA DRIVE implementation. For the cost of a small mission, the DRIVE initiative
recommends augmentations to NASA mission-enabling programs that have been carefully chosen to
maximize the effectiveness of the program overall. Six of the DRIVE sub-recommendations have cost
impact for NASA. Of these, NASA Mission Guest Investigator would require a cost allocation within
STP and LWS missions of ~2% of total mission cost for a directed guest investigator program. The other
five, NASA LCAS Microsatellites (LCAS), MO&DA augmentation (MODA), Heliophysics Science
Centers (HSCs), Heliophysics Instrument and Technology Development Program (HITDP), and Multi-
agency Laboratory Experiments (Lab), are shown in Figure 5.15. They have been phased with a slow
start because of budget constraints, and in sequence that allows for time to develop and ramp up new
programs. Note that the MO&DA augmentation begins in 2016, at a time when the SDO will have
moved out of prime mission, adding greatly to data covered by the general GI program. Implementation
of the NASA portion of DRIVE ramps up by 2022 to an augmentation to existing program lines that is
equivalent to approximately $33 million in current (2013) dollars. (In the developing this figure, the
survey committee assumes a 2.7% rate of inflation, which is what NASA currently assumes as the
inflation factor to be used for its new starts.)
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FIGURE 6.5 Recommended STP program budget with associated mission cadence. The dashed line
represents the recommended funding level for the STP Program including a 2% inflation slope. Funding
at the full level occurs in approximately 2019 with a 4-year mission cadence beginning with IMAP and
then continuing with DYNAMIC and MEDICI. The dips between missions are intentional with the
objective of allowing for both technology development and mission extensions.
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FIGURE 6.6 Recommended LWS program budget with associated mission cadence. The dashed line
represents the recommended based funding level for the LWS Program including a 2% inflation slope.
Funding at the full level occurs near the end of the decade with a 6-year mission cadence beginning with
GDC. The “bumps” in the missions are intentional in order to achieve the most cost-effective
implementation at the preferred cadence. The actual bump will be based on mission cost and the
associated development plan.
DECISION RULES AND AUGMENTATION PRIORITIES
The recommended program for NASA addresses important and highly compelling science
objectives in a cost effective manner. However, the committee recognizes that an already significantly
constrained program could face further budgetary challenges. To further guide the allocation of
resources, the committee recommends the following “decision rules.” Decision rules are required to
preserve an orderly and effective program in the event that less funding than anticipated is available, or
some other disruptive event occurs. The decision rules need to ensure that under any funding profile,
balanced progress can be made across the sub-disciplines of solar and space physics, and that the only
adjustment that is possible, i.e., the cadence of NASA assets, is properly applied.
The rules should be applied in the order shown to minimize disruption of the higher-priority
program elements.
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Recommended Decision Rules for Maintaining Balance Under More Constrained Budgets
Decision Rule 1. Missions in the STP and LWS lines should be reduced in scope or delayed to
accomplish higher priorities (see below for explicit triggers for review of the Solar Probe Plus
mission1).
Decision Rule 2. If further reductions are needed, the recommended increase in the cadence of
Explorer missions should be reduced, with the current cadence maintained as the minimum.
Decision Rule 3. If further reductions are still needed, the DRIVE augmentation profile should be
delayed, with the current level of support for elements in the NASA research line maintained as
the minimum.
Rule 1 calls for the reduction in scope or delay of missions in the LWS or STP lines as the first
line of defense against budget stress. However, the committee is aware that in the early years of the
decade there is very little flexibility in the NASA heliophysics program. Only Solar Probe Plus (SPP) is
not already in Design and Development, Phase C/D. SPP science remains important and timely (See Box
6.1), but the mission is costly and technically challenging. Significant cost growth beyond the current cap
threatens to disrupt the balance of the total program and should not be accepted without careful
consideration. While a low-cost delay imposed early in the decade may have minimal impact, the
committee otherwise recommends the following specific triggers for NASA to initiate a review of the
SPP mission in order to maintain program balance during the first 5 years:
Trigger 1: A decrease in the heliophysics budget expected to cause an interruption in the
current cadence of Heliophysics Explorers lasting more than 1 year, or that would impact
the remainder of the core research program.
Trigger 2: A decrease in the heliophysics budget that prevents the Heliophysics Division
from launching SPP and at least one new STP mission before 2022.
Trigger 3: An increase in the total SPP life-cycle cost above NASA’s projected $1.23 billion
level,2 irrespective of where the cost growth occurs.
The committee emphasizes that what is called for is a review by NASA, in which the expected
outcome will be actions by NASA with regard to SPP that preserve a program of balanced progress in
heliophysics throughout the decade.
The survey committee notes that the resources assumed in crafting this decadal survey’s
recommended programs are barely adequate to make the required progress; with reduced resources,
progress will be inadequate. It is also evident that with increased resources, the cadence of the assets by
which the nation pursues its program could be increased with a concomitant increase in the pace of
scientific discovery and societal value. We therefore recommend the following augmentation priorities to
aid in implementing a program under a more favorable budgetary environment:
1
In accordance with its charge, the survey committee did not re-prioritize any NASA mission that was in
formulation or advanced development. In June 2011, the survey committee’s charge was modified by NASA to
include a request for it to present “decision rules” to guide the future development of the Solar Probe Plus mission.
2
The committee understood the life-cycle costs of SPP to be approximately $1.23 billion as of September 2011,
which is consistent with the President’s FY 2012 budget request that was announced in February 2011. NASA
informed the survey committee that funding already appropriated for the advanced technologies required for SPP
have retired substantial technical risk. Note: Lifecycle costs do not include potential mission extensions.
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Recommended Augmentation Priorities for Maintaining Balance Under More Favorable Budgets
Augmentation Priority 1. If even modest additional financial resources can be made available
early in the decade, the implementation of the DRIVE initiative should be accelerated.
Augmentation Priority 2. Given sufficient funds throughout the decade, the Explorer line should
be further augmented so as to increase the cadence and amount of funding available for missions
including Missions of Opportunity.
Augmentation Priority 3. Given further budget augmentation, the cadence of STP missions
should increase to allow the recommended third-priority mid-sized science target (MEDICI) to be
initiated in this decade.
Augmentation Priority 4. The major-mission line recommendation (GDC) should be
implemented in the most cost-effective manner, if possible with a funding “bump” as shown in
Figure 6.1.
BEGIN BOX**********************************************************************
BOX 6.1
Solar Probe Plus – A Mission to the Core of the Heliosphere
Solar Probe Plus (SPP) will travel closer to the Sun than any other spacecraft and explore the
innermost region of our solar system—the corona. The 2002 Decadal Survey recommended a solar probe
intended to, “determine the mechanisms by which the solar corona is heated and the solar wind is
accelerated and to understand how the solar wind evolves in the innermost heliosphere.” Our survey finds
that the scientific rationale for a solar probe remains compelling and concludes that SPP meets that
challenge. SPP will study the streams of charged particles the Sun hurls into space from a vantage point
where the processes that heat the corona and generate the solar wind actually occur. SPP will repeatedly
sample the near-Sun environment and, using in situ measurements, reveal the mechanisms that produce
the fast and slow solar winds, coronal heating, and the transport of energetic particles.
The region inward of 0.3 AU is one of the last unexplored frontiers in our solar system. Discovering
how the solar wind originates and evolves in the inner heliosphere requires in situ sampling of the plasma,
energetic particles, magnetic field, and waves as close to the solar surface as possible. SPP measurements
will determine how energy flows upward in the solar atmosphere, heating the corona and accelerating the
solar wind. SPP will also reveal how the solar wind evolves with distance in the inner heliosphere. During
the past decade remote observations have revealed much about particle acceleration, heating, plasma
turbulence, waves, and the flows of mass and energy in the corona. In the survey committee’s view, these
observations only increase the need for measurements from this critical region.
The current solar probe differs in several respects from the mission envisioned in 2002. The closest
approach for SPP is 9.5 solar radii instead of 4 solar radii (Figure 6.1.1). The loss in proximity is
significant, but more than compensated for by the opportunity to spend far more time close to the Sun and
gather observations spanning half a solar cycle. This latter feature in particular makes the timing of the
mission with respect to the solar activity cycle a less significant issue. SPP orbits in the ecliptic plane
instead of a polar plane and thus leaves the polar regions unexplored. Nevertheless, fast solar wind
streams typical of polar coronal holes will still be adequately sampled, albeit at larger radial distances
from the Sun. Only one remote sensing instrument remains on SPP, but the most significant impairment
comes from the lack of in situ solar wind composition measurements; the survey committee urges NASA
to consider restoring this capability. However, in most other aspects SPP offers the prospect of a
substantially enhanced scientific return compared to the earlier solar probe concept.
The four science investigations provide a combination of in situ and remote sensing capability. Three
in situ instruments make comprehensive measurements of the solar wind ion and electron thermal plasma,
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of suprathermal and energetic particles, and of magnetic and electric fields from DC to high frequencies.
A side-looking imager provides both global context and quasi-in situ measurements of density and dust in
the corona from 2.2 - 20 Rs.
FIGURE 6.7 A simulated view of the Sun and inner heliosphere seen from above the pole illustrating the
revamped trajectory of Solar Probe Plus during its 19 near-Sun passes inside 30 Rs. The spacecraft spends
nearly 1000 hours within 20 Rs of the Sun and 30 hours within 10 Rs. The three-month near-ecliptic orbit
allows repeated measurements of the slow wind from the streamer belt as well as of the fast wind from
equatorial coronal holes. Terrestrial observatories, from both ground and space, will provide global
context measurements. SOURCE: NASA, Solar Probe Plus: Report of the Science and Technology
Definition Team, NASA/TM-2008-214161, NASA Goddard Space Flight Center, Greenbelt, Md., July
2008.
END BOX***************************************************************************
INTERNATIONAL COLLABORATIONS
Collaborations between NASA and foreign space agencies have historically achieved major
science at a relatively low cost to the United States. Missions indicated with an asterisk in Figure 6.2 are
examples of such international collaborations. These include SOHO, Ulysses, Yohkoh, CLUSTER,
Hinode, and Solar Orbiter. Collaborations with the Japanese space agency have been particularly fruitful,
as investments of Explorer-sized funds have resulted in full U.S. participation in major missions (Yohkoh,
Hinode). Such missions leverage U.S. investments while simultaneously sustaining a U.S. leadership role
in science.3
Opportunities for NASA to collaborate with other nations, and in so doing to obtain high science
return for relatively low cost, continue to arise. The Solar-C mission, a follow-on to Yohkoh and Hinode
3
At the same time, collaborations with international partners add complexity and risk that must be actively
managed. See, for example, National Research Council, U.S.-European Collaboration in Space Science, The
National Academies Press, Washington, D.C, 1998.
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that will study the magnetic coupling of the lower solar atmosphere and the corona, has been confirmed
by Japan and would greatly benefit from contributions of instrumentation from the U.S. A mission
concept has also been developed in Japan, Canada, and Europe that involves a fleet of spacecraft
performing simultaneous in situ measurements of fields and plasmas at key locations in the
magnetosphere. Finally, NASA support for the U.S.-Taiwanese FORMOSAT-3/COSMIC microsatellite
science mission for weather, climate, space weather, and geodetic research illustrates the range of
possible collaborative opportunities that might arise. The augmented Explorer line is the recommended
funding source for participation in most such international collaborations.
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