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James Webb Space Telescope
JWST History : 2009-2010

Passing The Mission Critical Design Review (MCDR)


As the President’s budget was released, the Project made official a launch slip to June 2014 and the MCDR to April 2010.

In 2009, the Spacecraft system(avionics, computer, antennae, thrusters, and solar array) passed its PDR. This design and development of this system was purposely delayed for financial reasons, as was the development of the Science and Operations Center.

Other systems passed their CDRs in preparation for the mission CDR in 2010: the ISIM in March, the OTE in October, the Backplane structure in December. The flight versions of these systems had been under construction prior to CDR and could now be completed and delivered to NASA. In September, the ISIM structure was delivered to GSFC.

Northrop Grumman completed several intermediate scale cryogenic tests to build confidence in the Observatory design and modeling. NGC completed a test of a portion of the central core during April and May and a 1/3 scale sunshade test in December.

All the instrument Engineering units were being integated or in test in 2009 to prepare for their delivery to GSFC in 2010.


The Sunshield system passed its CDR in January. The Project passed its MCDR in April. The only remaining liens on the program were financial (see below) and a separate CDR for the Spacecraft system in 2011 (the spacecraft is deemed to have the most off-the-shelf components).

In the meantime, the technical progress was impressive. All the instrument engineering units were delivered to GSFC to be tested and integrated into the ISIM structure, prior to the delivery of the actual flight units. The NIRSpec and MIRI flight units were completely integrated and undergoing testing at their respective development contractors.

During the summer, Ball Aerospace oversaw the gold coating of four of the flight mirrors: the first flight segment engineering unit and segment A-4 and the secondary and tertiary mirrors. The remaining mirrors were on a track to being delivered by summer 2011. This would complete a seven year development program.

In August, the National Research Council released the decadal report for Astronomy and Astrophysics. Although Webb was not under their review, its importance for science in the coming decades played a large role in their report and their first priority for new missions (WFIRST, a wide-field IR imaging mission). Both NASA and the astronomy community were concerned that growing costs for JWST would delay the implementation of WFIRST and other missions until the end of the decade. NASA HQ chartered a Test Assessment Task to review and recommend a simplified test program for JWST, particularly for the integrated OTE/ISIM testing at JSC.