Infrared Astronomical Satellite (IRAS)

First space observatory to map the entire sky at infrared wavelengths. IRAS, a U.S.-U.K.-Netherlands satellite, was launched in 1983 and carried a 60-cm (24-in.) telescope. It observed disks of minute, solid dust particles around some young stars, which suggests that these are in the process of forming planetary systems. It also discovered many previously unknown galaxies that emit most of their energy at infrared wavelengths.

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