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Solar and Space Physics: A Science for a Technological Society
NASA PROGRAM IMPLEMENTATION
131
event occurs. The decision rules need to ensure that, under any funding profile, balanced progress can be
made across the subdisciplines of solar and space physics and that the only adjustment that is possible,
i.e., the cadence of NASA assets, is properly applied. To further guide the allocation of resources, the
committee recommends the following decision rules.
Recommended Decision Rules for Maintaining Balance Under More Constrained Budgets
The decision rules should be applied in the order shown to minimize disruption of the higher-priority
program elements.
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 mission 1 ).
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 (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.
1 In accordance with its charge, the survey committee did not reprioritize 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 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: Life-cycle costs
do not include potential mission extensions.
Solar and Space Physics: A Science for a Technological Society
NASA PROGRAM IMPLEMENTATION
131
event occurs. The decision rules need to ensure that, under any funding profile, balanced progress can be
made across the subdisciplines of solar and space physics and that the only adjustment that is possible,
i.e., the cadence of NASA assets, is properly applied. To further guide the allocation of resources, the
committee recommends the following decision rules.
Recommended Decision Rules for Maintaining Balance Under More Constrained Budgets
The decision rules should be applied in the order shown to minimize disruption of the higher-priority
program elements.
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 mission 1 ).
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 (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.
1 In accordance with its charge, the survey committee did not reprioritize 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 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: Life-cycle costs
do not include potential mission extensions.