Well-cooled telescope

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). 

The possibility of observing the outburst of Supernovae at the remote Galaxy regions, invisible within optical band because of interstellar extinction using thermal IR-radiation of interstellar dust heated by Supernova outburst is discussed in this paper. The investigation of this phenomenon by means of cooled IR-telescopes will allow the Supernova outburst parameters to be determined and the characteristics of the interstellar dust distribution to be studied. The similar effects can be detected in the vicinities of the well-known remnants of Supernovae, in particular, near Tycho Brahe and Cassiopeia A Supernovae. 

Consider an Earth orbiting telescope of 2.7 m diameter, equipped with a Michelson interferometer operating between 300 and 500 cm with a spectral resolution of 0.02 cm This is an entirely fictitious case and does not refer to an existing or planned project. Of course, as a useful observation, the hydrogen dimer feature at 356 cm could be examined on Jupiter (Frommhold et al., 1984) and, at the same time, one could search for hydrocarbon emissions from the Jovian stratosphere. Consider also observations with a 40 arcsecond field of view. The A 2 of the telescope is 1.69 x 10 cm sr. With an interferometer beam of 4 cm diameter the system etendue is still telescope limited. It is assumed that the interferometer is equipped with a cryogenically cooled bolometer with a NEP of 1 x lO" " WHz 5. To calculate the contributions from the interferometer, telescope, and planet to the background noise at the detector, we evaluate Eq. (5.11.33) for several temperatures and a passband of 200 cm as well as 2 cm . Then we use Eq. (5.11.21) to find the individual contributions of the different background-noise sources to the systems noise (Table 5.8.1). 

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