Cryomechanisms for the instruments MIRI and NIRSpec on the James Webb Space Telescope (JWST)

Abstract

The Mid-Infrared Instrument (MIRI) and the Near-Infrared Spectrograph (NIRSpec) of the JWST require various mechanisms for positioning optical elements in cryo-vacuum environment (7K resp. 35K): Wheels for exchanging filters, gratings and prisms, a flip mirror for switching between the sky and internal calibration sources and a linear actuator for refocusing purposes will have to be developed. In order to fulfill the stringent requirements of the mission, comprising to survive a warm ARIANE 5 launch, to guarantee high accuracy positioning in the cryovacuum with minimal power dissipation, to be operational with high reliability during 10 years of lifetime and to be testable under various environmental conditions, we propose a low cost and low schedule risk approach, based on the successful flight experience and qualification heritage from ESA's infrared missions ISO and HERSCHEL.

Recent Interferometry Applications in Topography and Astronomy

“…The water in the atmosphere attenuates the transmission of the IR radiation so most IR telescopes perform best in space. (Hofferbert et al, 2003;Kessler & Harvit, 1993;Lamarre, 1993;Lemke et al, 2005;Mather, 1993;Matsumoto & Murakami, 1996;Scholl & Paez, 1997a;Touahri et al, 2010). The great disadvantage of the space-based IR telescopes is that their instruments require cooling, often to liquid Helium temperatures (Beeman & Haller, 2002;Latvakoski et al, 2010).…”

Interferometry to Detect Planets Outside Our Solar System

“…The water in the atmosphere attenuates the transmission of the IR radiation so most IR telescopes perform best in space. (Hofferbert et al, 2003;Kessler & Harvit, 1993;Lamarre, 1993;Lemke et al, 2005;Mather, 1993;Matsumoto & Murakami, 1996;Scholl & Paez, 1997a;Touahri et al, 2010). The great disadvantage of the space-based IR telescopes is that their instruments require cooling, often to liquid Helium temperatures (Beeman & Haller, 2002;Latvakoski et al, 2010).…”