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Astronomy

The Role of Cosmic Background Radiation in Big Bang Theory

Quick fact

The cosmic microwave background radiation was discovered accidentally in 1965 by Arno Penzias and Robert Wilson, who were trying to eliminate interference from pigeon droppings in their radio antenna. Its nearly perfect blackbody spectrum matches the prediction of a universe that was once a hot, dense plasma.

Why this is interesting

Imagine if you could see the flash of the Big Bang itself, but it has been stretched and cooled over 13.8 billion years into a faint whisper of light. That whisper is all around us—how did scientists discover it, and what does it tell us about our cosmic origins?