TALK ABSTRACT:
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The James Webb Space Telescope (JWST) is the first in a possible series
of deployable infrared to millimeter wave space telescopes.  The design
process for JWST has already produced ultra-light mirrors, deployment
methods, and cooling approaches that could lead to much larger and more
capable equipment in the future.  We will describe the progress on JWST
in the context of its history and illustrate some new concepts for
future missions that spring from it. These include the SAFIR (Single
Aperture Far Infrared) telescope and the SPECS (Submillimeter Probe of
the Evolution of Cosmic Structure). The JWST will operate at the
Sun-Earth Lagrange point L2, where radiative cooling lowers the
telescope and instrument temperatures to about 35 K. It will have an
18-segment beryllium primary mirror with a 25 m2 area fitting inside a
6.6 m circumscribed circle, and will provide spectroscopy and imaging over
the wavelength range from 0.6 to 28 microns. It is planned for launch in
2011 on an Ariane 5 rocket.  The project is a partnership of NASA, ESA,
and CSA, and the prime contractor is Northrop Grumman.  See
http://www.jwst.nasa.gov for more details on JWST.

Missions to follow JWST will be able to draw on a greatly expanded
technological base. Other uses ranging from Earth sciences to
surveillance demand large space telescopes and interferometric systems,
and the infrastructure for remote assembly and astronaut servicing will
continue to improve as the Space Station is completed and experience is
gained.

The SAFIR (http://safir.jpl.nasa.gov/, http://safir.gsfc.nasa.gov/) and
SPECS (http://space.gsfc.nasa.gov/astro/specs/) missions have been
approved by NASA for Vision Mission studies, now in progress.  SAFIR
was mentioned prominently in the 2000 NRC Decadal Report on Astronomy as
"the recommended next step in exploring the cosmos at far-infrared
wavelengths." The report furthermore states that SAFIR could "form the
basis for developing a far-infrared interferometer in the succeeding
decade."  I will summarize both of these concepts and the unique science
capabilities enabled by these missions as well as outline how they might
further develop as other projects come on line, scientific priorities
evolve, and technological capabilities expand.