Cosmic microwave background

Cosmology Early Universe
Cosmic microwave background

Electromagnetic radiation as a remnant from an early stage of the universe in Big Bang cosmology

The cosmic microwave background is microwave radiation that fills all space. It is a remnant that provides an important source of data on the primordial universe. With a standard optical telescope, the background space between stars and galaxies is almost completely dark. However, a sufficiently sensitive radio telescope detects a faint background glow that is almost uniform and is not associated with any star, galaxy, or other object. This glow is strongest in the microwave region of the radio spectrum. The accidental discovery of the CMB in 1965 by American radio astronomers Arno Penzias and Robert Wilson was the culmination of work initiated in the 1940s.

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A Measurement of Excess Antenna Temperature at 4080 Mc/s. (1965)

Penzias, A. A., Wilson, R. W.

Cosmic Black-Body Radiation. (1965)

Dicke, R. H. et al.