Cosmic background radiation

Common card · No. 406550

Cosmic background radiation is electromagnetic radiation that fills all space. The origin of this radiation depends on the region of the spectrum that is observed. One component is the cosmic microwave background. This component is redshifted photons that have freely streamed from an epoch when the Universe became transparent for the first time to radiation. Its discovery and detailed observations of its properties are considered one of the major confirmations of the Big Bang. Background radiation is largely homogeneous and isotropic. A slight detectable anisotropy is present which correlates to galaxy filaments and voids. In 1965, while investigating an unexplained excess noise in an exceptionally sensitive microwave antenna,Arno Penzias and Robert Wilson systematically eliminated instrumental and terrestrial sources and discovered the cosmic microwave background radiation, which shows that the early universe was dominated by a radiation field of extremely high temperature and pressure...

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