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JWST History: 1997-2001
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James Webb Space Telescope
JWST History: 1997-2001

Reality Hits

1997-2000

During this period, the astronomical community at large began to join up to define more carefully and realistically the science drivers for NGST. The Ad-Hoc Science Working Group (SWG) was formed which came up with science goals centered around five themes:

  1. Cosmology and the Structure of the Universe
  2. The Origin and Evolution of Galaxies
  3. The History of the Milky Way and Its Neighbors
  4. The Birth and Formation of Stars
  5. The Origins and Evolution of Planetary Systems

Within these themes, the SWG developed the Design Reference Mission (DRM), a suite of 21 hypothetical key science observing programs for NGST, to which each design of NGST can be tested. The SWG furthermore came to an agreement as to what the core instrument package of NGST should be in order to maximally cover the science proposed in the DRM:

  • a large field of view near-IR camera,
  • a multi object near-IR spectrograph with at least 100 elements,
  • a general purpose mid-IR camera/spectrograph.

The Science Working Groups were also key in cementing the collaboration between NASA, the European Space Agency and the Canadian Space Agency.

In the same 1997-2000 period reality started to hit. Initial technology development was started, with a focus on:

  • lightweight mirrors,
  • wavefront sensing and control,
  • detectors, and
  • cryogenic actuators.

Trade studies were done, looking at a configuration with:

  • an 8m diameter, deployable mirror,
  • an Atlas V Launcher,
  • a satellite in L2 orbit, and
  • a large deployable sunshield.

At the end of 2000 the NGST project performed a careful Cost & Schedule analysis based on these trade studies and concluded that the envisioned design was over budget by several $100 million and that the schedule of mirror development would not allow a 2008 launch.

August 2000

NASA designated the STScI to be the Science and Operations Center for NGST. The GSFC/STScI collaboration, the success of the Hubble operations team, and the potential for reuse of Hubble software formed the basis for NASA’s selection.

At the end of 2000 the NGST project performed a careful Cost & Schedule analysis based on these trade studies and concluded that the envisioned design was over budget by several $100 million and that the schedule of mirror development would not allow a 2008 launch.

2001

Realizing the budget and technology problems, the project had to accept the painful but necessary re-scope of NGST. To address both problems, the project management decided to reduce mirror size to 6m+. Two contractors put in a bid to be the prime contractor to build the telescope: TRW/Ball Aerospace and Lockheed-Martin.

September 2001

The Jet Propulsion Laboratory is selected by NASA as the implementing center for the NGST Mid-Infra-red Instrument (MIRI). (Press Release)