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James Webb Space Telescope
JWST History: 2007

Approaching Preliminary Design Review


In 2007, the NIRSpec and FGS/*TFI teams passed CDR. Nine of the ten technology development programs demonstrated TRL-6 flight-like performance prior to the T-NAR in early March. The tenth, the late-starting cryo-cooler, was considered to pass its performance goals on the basis of tests of a JWST-specific design and a very similar USAF device developed and tested by Northrop Grumman prior to the T-NAR. The successful tests allowed the Project teams to continue the design and development of the observatory without the risk of having to substitute alternative technologies or scrubbing science capabilities.

In the spring of 2007, Axsys completed machining and figuring of all the Be optics and shipped the remaining pieces to Tinsley for grinding and polishing.

In the summer of 2007, NASA and ESA and NASA and CSA officially signed their respective memorandum of understanding for the development and operations of JWST.

In August 2007, a NASA and STScI team successfully tested the thermal stability of a representative portion of the ISIM support structure, again using the speckle interferometer.

The STScI and GSFC hosted a science conference entitled “Astrophysics in the Next Decade: JWST and Concurrent facilities” in Tucson in September 2007. Over 200 scientists participated in the conference, listening and discussing presentations on twenty science themes. The accompanying book was published in 2009.

*The Canadian Space Agency (CSA) discontinued work on the Tunable Filter Imager (TFI) in 2011 and decided to provide a reconfigured instrument - the Near InfraRed Imager and Slitless Spectrograph (NIRISS).


The Project team successfully passed the Preliminary Design Review in March 2008 and the related Non-Advocated Review in April. In July, NASA formally approved the transition of the Project into Phase C/D (implementation and testing).

On the technical front, the first flight primary mirror segment completed its fine-polishing and cryo-testing. This was a critical milestone in the mirror development program, proving that the mirror polishing process could deliver a mirror with the appropriate figure prior to cryo-polishing. Because of improvements in the processing flow, many of the remaining segments had almost reached this quality by the end of the first cryo-test.

Bonding began on the flight mirror backplane in December.