Spitzer’s Cold Look At Space

From American Scientist:

To get a clear view of infrared emissions from celestial objects, the Spitzer Space Telescope has been cryogenically cooled—and what sights it has seen.

In astrophysical observations, more is more—imaging across multiple wavelengths leads to richer information. One electromagnetic band in which most celestial bodies radiate is the infrared: Objects ranging in location from the chilly fringes of our Solar System to the dust-enshrouded nuclei of distant galaxies radiate entirely or predominantly in this band. Thus, astrophysicists require good visualization of these wavelengths. The problem, however, is that Earth is a very hostile environment for infrared exploration of space, as the atmosphere also emits in the infrared spectrum and additionally absorbs much of the incoming signal. Even heat produced by a telescope itself can degrade its own clarity.

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