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Astronomy

Cosmic Microwave Background: A Window to the Early Universe

Quick fact

The CMB is the oldest light we can see, emitted when the universe was just 0.003% of its current age of 13.8 billion years.

Why this is interesting

When you tune an old TV between channels, about 1% of the static you see is the faint afterglow of the Big Bang. But how can that static reveal the universe when it was only 380,000 years old?