background radiation
noun
: the microwave radiation pervading the universe that exhibits a corresponding blackbody temperature of 2.7 K and that is the principal evidence supporting the big bang theory
called also cosmic background radiation
Examples of background radiation in a Sentence
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They also can be produced by interactions between high-energy cosmic rays and the universe's background radiation.
—
Doyle Rice, USA TODAY, 13 Feb. 2025
Earth is naturally radioactive, so we are all constantly exposed to a small amount of background radiation.
—Robert Lea, Space.com, 12 Feb. 2025
By comparison, a person on Earth receives an average of 2 mSv every year from just background radiation, NASA said.
—Mary Kekatos, ABC News, 5 Sep. 2024
We're constantly exposed to background radiation just by living on Earth.
—Rhett Allain, WIRED, 23 Feb. 2024
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Doyle Rice, USA TODAY, 13 Feb. 2025
Earth is naturally radioactive, so we are all constantly exposed to a small amount of background radiation.
—Robert Lea, Space.com, 12 Feb. 2025
By comparison, a person on Earth receives an average of 2 mSv every year from just background radiation, NASA said.
—Mary Kekatos, ABC News, 5 Sep. 2024
We're constantly exposed to background radiation just by living on Earth.
—Rhett Allain, WIRED, 23 Feb. 2024
See all Example Sentences for background radiation
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“Background radiation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/background%20radiation. Accessed 20 Feb. 2025.
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