Far infrared multi-frequency observation of interstellar dust clouds

Diffuse interstellar dust emission at wavelengths between 0.5 and 2 mm has been detected by the ARGO 1993 balloon borne telescope. The instrument scanned the Galactic plane in Aquila and several cirrus clouds in Aries, Taurus and Hercules. The data are spatially consistent with the IRAS 100 μm sky maps, and the spectral behaviour is consistent with a single temperature thennal spectrum with T _d ∼ 21 K and a spectral index of emissivity α ∼ 1.5.