Astronomers have detected the faintest millimeter-wave source ever observed. By accumulating millimeter-waves from faint objects throughout the Universe, the team finally determined that such objects are 100 percent responsible for the enigmatic infrared background light filling the Universe.

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Astronomers have detected the faintest millimeter-wave source ever observed. By accumulating millimeter-waves from faint objects throughout the Universe, the team finally determined that such objects are 100 percent responsible for the enigmatic infrared background light filling the Universe.