Telescopes, cryogenic

On the last three decades, several space experiments with parts at very low temperatures have been flown. Among these, we mention IRAS (Infrared Astronomical Satellite) launched in 1983 (see Fig. 14.1), COBE (Cosmic Background Explorer) launched in 1989, ISO (Infrared Space Observatory) launched in 1995 and Astro-E (X-ray Observatory), launched in 2000 with instrumentation at 65 mK [35], Some cryogenic space missions are in the preparation or in final phase in Europe, USA and Japan. For example, ESA is going to fly Planck (for the mapping of the cosmic background radiation) and Herschel (called before FIRST Far Infrared and Submillimetre Telescope ) [36], These missions will carry experiments at 0.1 and 0.3 K respectively. 

Spitzer Space Telescope a cryogenically cooled infrared space telescope on a thermally stable Earth-trailing orbit operated by NASA. The telescope has very sensitive imaging capabilities with the IRAC (3 to 8 pm) and MIPS (24— 160 pm) cameras as well as spectroscopic capability with the IRS instrument (5-40 pm). 

Offermann, D., K.-U. Grossman, P. Varthol, P. Knieling, M. Riese, and R. Tank, Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere (CRISTA) experiment and middle atmosphere variability. J Geophys Res 104, 16,311, 1999. 

Riese, M., R. Spang, P. Preusse, M. Ern, M. Jarisch, D. Offermann, and K.-U. Grossmann, Cryogenic Infrared Spectrometers and Telescope for the Atmosphere (CRISTA) data processing and atmospheric temperature and trace gas retrieval. J Geophys Res 104, 16,349, 1999. 

The first use of solid hydrogen as a cryogen on a flight mission was for cooling the LWIR focal planes in the Spatial Infrared Imaging Telescope III (SPIRIT III)... 

J. Fischer, T. Klaassen, N. Hovenier, G. Jtikob, A. Poglitsch, O. Sternberg, Cryogenic far-infrared laser absorptivity measurements of the herschel space observatory telescope mirror coatings. Appl. Opt. 43(19), 3765-3771 (2004). doi 10.1364/A0.43.003765. http //ao.osa.oig/abstract. cfm URI=ao-43-19-3765... 

Aerospace Industry AppUcations. NASA s space program utilizes cryogenic liquids to propel rockets. Rockets carry liquid hydrogen for fuel and liquid oxygen for combustion. Cryogenic hydrogen fuel is what enables NASA s workhorse space shuttle to get into orbit. Another application is using liquid helium to cool the infrared telescopes on rockets. 

Since 1970 the Air Force Geophysics Laboratory has conducted a infrared survey program in order to obtain the spatial and brightness distribution of a representative sample of the types of celestial objects which emit strongly in the 3 to 30 pm spectral region. The survey data, presented herein, were obtained with small cryogenically cooled telescopes flown above the atmosphere by sounding rockets. 

A 1-METER CRYOGENIC TELESCOPE FOR THE SPACE SHUTTLE 3. CONTAMINATION AND OPERATIONS... 

Integration of the focal plane instruments and loading of the cryogenic systems will take place prior to the installation of LIRTS in the Orbiter bay. The telescope will be continuously... 

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