Daily History — On This Day

Added: 2026-05-25

[00:00:00]Welcome to Daily History. Every day in history tells a story. This is the 20th of May.

[00:00:06]At a massive horn-shaped antenna in Holmdel, New Jersey, two scientists are hunting for the source of an irritating hiss in their equipment.

[00:00:14]Arno Penzias and Robert Wilson have checked everything, even scraping pigeon droppings from the antenna, but the mysterious noise refuses to disappear.

[00:00:23]The scientific world was locked in a fierce debate between two theories of the universe, the explosive Big Bang versus the eternal steady state.

[00:00:33]What seemed like a technical glitch was about to settle the argument forever.

[00:00:38]Working at Bell Labs, Penzias and Wilson aimed their 20-ft Holmdel horn antenna at the sky, expecting silence between radio sources.

[00:00:46]Instead, they detected a constant low-level static coming from every direction, day and night, summer and winter.

[00:00:54]After months of frustration, a phone call changed everything.

[00:00:58]Physicists at nearby Princeton were actively searching for radiation left over from the birth of the universe.

[00:01:05]Their measurement of 3.5 Kelvin matched theoretical predictions almost perfectly.

[00:01:10]The cosmic microwave background, the afterglow of the Big Bang itself, had been found by accident.

[00:01:17]In 1978, Penzias and Wilson received the Nobel Prize for their discovery.

[00:01:22]Today, satellites map the CMB in exquisite detail, revealing the seeds of galaxies and ripples of ancient light.

[00:01:29]Every modern understanding of how our universe began traces back to that stubborn hiss in New Jersey. What other cosmic secrets might be hiding in plain sight?

[00:01:39]Follow Daily History for a new story every single day.