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.
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cosmic background radiation in Science

cosmic background radiation

  1. 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
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