AAAC Presentation
JWST Status
Eric P. SmithJWST Program Scientist
11-October-2005 2AAAC Presentation
Topics
• JWST Cost Growth
• Science Assessment Team Findings and
Program Response
• JWST Plans
11-October-2005 3AAAC Presentation
Recent Programmatic Changes
~$1B net cost growth• ~$180M at NGST and ~$35M at subs
– Reevaluation of I&T effort (metrology, GSE)– Additional launcher-related testing requirements– Reallocation of technical resources (e.g., mass and power budgets)
among observatory elements
• ~$85M in instruments and related elements• ~$160M of recommended added contingency funding• ~$600M for 22 month launch slip to 6/2013
– Launch vehicle uncertainty and lack of TAA– Budget profile limitations in FY06 and 07– Schedule risk reduction (negotiated w/ NGST)
• Technology maturation efforts remain on schedule
11-October-2005 4AAAC Presentation
Science Assessment Team (SAT) Findings
• “… the scientific case for the JWST mission has become even stronger since its highest ranking by the Decadal report in 2000.”Retain current 6.5 meter primary aperture Retain current instrument complementPriority on unique capabilities, i.e., performance
longward of 1.7 microns, given the limitations of other future ground and space-based assets
• Use prioritization as a guide to reduce cost and risk
11-October-2005 5AAAC Presentation
SAT-Endorsed Changes
SAT Recommendation Program ResponseDe-emphasize or eliminate low-priority instrument capabilities
See next chart
Simplify Integration & Test Revising Integration & Test plan (e.g., “cup-up” testing) ~$130M & 3 months savings (TBR)
Eliminate 1 µm encircled energy requirement
Eliminate Level 1 requirement (possible degradation of imaging performance at shortest wavelengths)enables simplified I&T (see above) reduces mirror polishing schedule risk
Relax scattered light requirement Change cleanliness levels (acceptable potential reduction in sensitivity)enables “cup-up” layout, simplified I&T (see above)
Relax optical stability requirement Change tstab = 30 days to tstab = 14 days (reduce observing efficiency ~1%)reduces telescope backplane development risk
Relax/eliminate anisotropy requirement Eliminate Level 2 Point-Spread-Function anisotropy requirement (no expected science impact)reduces telescope development risk
Maintain mission lifetime goal No change
11-October-2005 6AAAC Presentation
SAT-Endorsed Changes:Science Instruments
SAT Recommendation Program ResponseMaintain short wavelength ( < 1.7 µm) instrument capabilities, but eliminate JWST architecture (ISIM level and above) requirements for testing/verification of these capabilities
Revising Integration & Test and verification plans to comply with recommendation (fewer reverifications of lowest priority science modes, elimination of potentially infeasible tests)specific cost and schedule benefits TBD
Maintain current MIRI coronography capabilities
No change
Retain single channel tunable filter Eliminate short wavelength portion of tunable filter (loss of lowest priority science capability)saves 80kg; improves mass marginreduces complexity; enhances likelihood of on-time delivery of FGS
11-October-2005 7AAAC Presentation
Moving Forward
Consult scientistsregarding JWST’s
scientific significance,prioritize JWST’s
capabilities
Revise mission development plan
Preliminary Final
Independent Assessment
Formulate budget
May’05 Apr’06
Science Assessment Team (SAT)
NASA’s Independent Program Analysis Office (IPAO)
11-October-2005 8AAAC Presentation
JWST Replan
• It’s not over…– Additional study of I&T and verification plan forecast with
ultimate conclusion around April 06
• Will this happen again?– History of replans
• 8m 6m diameter requirement, Fall 2000• Replan I, Fall 2002• Replan II, Summer 2005• (see chart 9)
• Will the science change?– No, first light goal combined with NAS decadal position prohibits
significant changes in observatory
11-October-2005 9AAAC Presentation
HST Spending History
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
0246810121416
Years-to-Launch
Fraction of Phase A-D Costs
HST (no servicing costs)
JWST (Projection)
11-October-2005 10AAAC Presentation
JWST Program Today
• Early emphasis on vigorous technology development to retire risk– Pacing items (primary mirror, detectors) already in Phase C/D and flight
production
• ~$820M (~20% of Phase A through D total) invested so far
today
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Concept Development Design, Fabrication, Assembly and Test
FormulationAuthorization
Non-Advocate Review(NAR)-Program Commitment-
Launch
science operations ...
Initial Confirmation Review (ICR)
Phase A Phase B Phase C/D Phase E
Formulation Implementation …
11-October-2005 11AAAC Presentation
SummaryActions being taken to address JWST cost and schedule changes
– Current estimated cost, inception through launch $3.7B– Current estimated cost, Oct’06 through launch $2.9B
• Science assessment complete– JWST reconfirmed as mission of paramount significance and priority– Scientific capabilities prioritized– Recommendations provide some cost savings and significant risk reduction; added
flexibility for program management
• Preliminary replanning complete, FY07 budget adjusted and submitted– Science assessment recommendations embraced, being implemented– Launch in June 2013
• Preliminary stage of independent assessment found program work plan fundamentally sound, but likely to need more time and money
Detailed replanning will be complete by April 2006– Fully implement embraced SAT changes– Follow-up independent review and assessment– Forms basis for FY08 budget development
AAAC Presentation
Mission ObjectiveStudy the origin and evolution of galaxies, stars and
planetary systems Optimized for infrared observations (0.6 – 28 m)
Organization– Mission Lead: Goddard Space Flight Center– International collaboration with ESA & CSA – Prime Contractor: Northrop Grumman Space Technology
– Instruments: – Near Infrared Camera (NIRCam) – Univ. of
Arizona– Near Infrared Spectrograph (NIRSpec) –
ESA– Mid-Infrared Instrument (MIRI) – JPL/ESA– Fine Guidance Sensor (FGS) – CSA Description
– Deployable telescope w/ 6.5m diameter segmented adjustable primary mirror
– Cryogenic temperature telescope and instruments for infrared performance
– Launch NET June 2013 on an ESA-supplied Ariane 5 rocket to Sun-Earth L2
– 5-year science mission (10-year goal)
James Webb Space Telescope (JWST)
www.JWST.nasa.gov
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Concept Development Design, Fabrication, Assembly and Test
FormulationAuthorization
NAR Launch
science operations ...
ICR(PNAR)
Phase A Phase B Phase C/D Phase E
Telescope
Primary Mirror (PM)
Cold, space-facing side
SunshieldSpacecraft Bus
Warm, Sun-facing side
Instrumentmodule
scale:
1 meter