cosmic background radiation

noun, Astronomy
1.
electromagnetic radiation coming from every direction in the universe, considered the remnant of the big bang and corresponding to the black-body radiation of 3 K, the temperature to which the universe has cooled.
Also called cosmic microwave background.
cosmic microwave background in Science
cosmic background radiation  
Weak radio-frequency radiation traveling through outer space with equal intensity in every direction. It is thought to be residual radiation from a period shortly following the big bang, when the universe was very hot. Also called microwave background.
cosmic microwave background in Culture

cosmic microwave background definition


The microwave radiation that arrives at the Earth from every direction in space. The detection of this radiation played an important role in acceptance of the Big Bang theory.

Note: This radiation is sometimes referred to as the “echo” of the Big Bang.