NGST 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:
- Cosmology and the Structure of the Universe
- The Origin and Evolution of Galaxies
- The History of the Milky Way and Its Neighbors
- The Birth and Formation of Stars
- 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.
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)
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