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Session 60 - Next Generation Space Telescope.
Oral session, Tuesday, January 14
Piers 4/5,

[60.04] Optical Telescope Assembly Concept for Next Generation Space Telescope

N. Wallace (TRW), M. Krim (Hughes Aircraft Co.), G. Horner (LRC/NASA)

A recent study by a TRW/HDOS/GSFC/LaRC/Swales team produced a conceptual design for an eight-meter diameter Next Generation Space Telescope (NGST). This space telescope would have a deployed primary mirror with active figure control of the mirror petals to give diffraction limited performance at one micron wavelength. The High Accuracy Reflector Development (HARD) scheme, utilizing special translation-rotation mechanisms and precision latches, would deploy and lock the primary mirror segments into place. Thin mirror faceplates on stiff, lightweight backing structure would allow the extremely low weight at moderate cost. The telescope would produce images and spectra from radiation in the 0.5 micron to 10 micron spectral interval, have a 10 arc-minute circular field of view, weigh about 1000 kg, and fit within the shroud of an Atlas II AS launch vehicle. A deployable sunshield and an L2 Lissajous orbit would give passive cooling to 30 K. This paper describes the baseline optics, structures, and control systems of the Optical Telescope Assembly design produced in the study. The associated technologies are discussed, with emphasis on the optics and mechanisms for the primary mirror. For the optics, different mirror materials, fabrication processes, structural configurations, controls configurations, and verification techniques were studied, and a preliminary wavefront error budget was produced. For mechanisms, concepts were produced for high resolution actuators with a large operating range and for active vibration suppression. The state-of-the-art of all these technologies is presented, the technological advances needed, and some preliminary plans for their development.


Program listing for Tuesday