Evaluation of the Implementation of WFIRST/AFTA in the Context of New Worlds, New Horizons in Astronomy and Astrophysics (2014) / Chapter Skim
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2 WFIRST in the Programmatic Context
2 WFIRST in the Programmatic Context
Pages 27-35
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From page 27... ...
as its highest-priority large space project, based on the compelling scientific case coupled with the maturity of the design and technologies and the medium-low technical risk and acceptable cost and schedule risk. The decadal survey committee planned the NWNH program in a cost-constrained environment that has worsened since the report's publication.
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-Omega implementation) , the project's own cost estimate for WFIRST/AFTA without the coronagraph, and a CATE performed by Aerospace contracted by NASA assessing both WFIRST/ Interim Design Reference Mission (IDRM)
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From page 29... ...
In the case of WFIRST/IDRM, Aerospace cited detector yield, integration of the 28 individual sensor chip assemblies on the focal plane, and maintaining calibration while on-orbit as challenging. Although the WFIRST/AFTA concept relies on fewer detector chips, Aerospace maintains the wide-field instrument at the top of the list of technical challenges.
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From page 30... ...
Although the cost of the more expensive Delta IV-H is included in the Aerospace CATE estimate of $2.1 billion (FY2012 dollars) , the risk that the gifted telescope hardware is incompatible with the vehicle loads is not included in the Aerospace analysis.
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From page 31... ...
For example, measured emissivities may prove higher than those assumed due to contamination or other factors, or there may be problems in isolating the warm regions from colder ones, either optically or mechanically. The low margin stems from the fact that the sensitivity is completely dominated by the telescope mirror temperature, and the thermal emission is a very steep function of temperature.
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It is, therefore, not possible to quantitatively assess the cost and risk impact to the WFIRST/AFTA program. In general, technology demonstration missions accept larger technical risk relative to flagship science missions.
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Finding 2-6: Introducing a technology development program onto a flag ship mission creates significant mission risks resulting from the schedule uncertainties inherent in advancing low-TRL hardware to flight readiness. The committee notes that a significant consideration in the NWNH recommendation of WFIRST as its top priority in the large space mission category was the low cost and technical risk.
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From page 34... ...
MISSION OPERATIONS COMPLEXITY NWNH was concerned about the expansion of scope that might make the mission more costly and affect NASA's ability to implement other aspects of the program. In particular, NWNH stated the following: 7 The committee considers the general investigator program to be an essential element of the mission, but firmly believes it should not drive the mission hardware design or implementation cost (p.
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From page 35... ...
In addition, the requisite level of guest investigator support must also be increased to support the expanded scientific scope. The committee is concerned that the operational costs, including scheduling and data management, as well as science support for the diverse observational program, might increase beyond the $42 million per year currently planned ($20 million per year for science and guest investigator grants and $22 million per year for operations)
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