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Astronomy

How the Cosmic Microwave Background Reveals the Early Universe

Quick fact

The CMB was discovered accidentally in 1965 by Arno Penzias and Robert Wilson, who were trying to eliminate a persistent 'noise' in their radio antenna. They later won the Nobel Prize for this discovery.

Why this is interesting

When you look at the night sky, you see stars and galaxies. But if you could tune your eyes to microwaves, you'd see the universe's baby picture—a glow that fills the entire sky, left over from just after the Big Bang.