Search for extragalactic backgrounds in the far-infrared

A novel method which involves the search for a peculiar spatial signature of the galactic component (such as its dipole anisotropy due to the observer's motion, which has to be aligned with the 3-K dipole anisotropy) is applied to the task of measuring the extragalactic diffuse radiation in the 100-1000 micron region, in the presence of strong atmospheric, interplanetary, and galactic dust emission sources. Upper limits of the order of 2 x 10 to the -12th watts/sq cm per sr per cm are obtained between 13 and 18/cm, for the diffuse radiation emitted by rich clusters, and of 5 x 10 to the -12th watts/sq cm per sr per cm, for radiation emitted by IR galaxies at 1.0 standard deviation.