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cosmic microwave background

Cultural  
  1. 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.


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

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The other looks much farther back in time, using the cosmic microwave background to estimate what the expansion rate should be today based on the standard model of cosmology.

From Science Daily Apr. 12, 2026

They’ve measured the cosmic microwave background, or leftover radiation from the Big Bang, with extremely high precision to help paint a picture of the first nanoseconds of the universe.

From Salon Jan. 17, 2025

Throughout the decades, numerous observations of how dust, gas, and ripples in the cosmic microwave background, or the leftover radiation from the primordial plasma of the universe, moved indicated that dark matter exists.

From Salon Dec. 26, 2024

For example, scientists have already compared the new quasar map with the oldest light in our cosmos, the cosmic microwave background.

From Science Daily Mar. 18, 2024

“This could lead to something really groundbreaking,” Dr. Soares-Santos said, comparing it to the discovery of the cosmic microwave background in the 1960s, which has since transformed physicists’ knowledge about the early universe.

From New York Times Jun. 28, 2023

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