Smart Luck: How the Big Bang Was Found by Accident [Slide Show]

Two astronomers recall almost mistaking light from the big bang for pigeon droppings

By Clara Moskowitz

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Horn Antenna:

​This six-meter radio telescope at Bell Labs in Holmdel, N.J., was the instrument on which the cosmic microwave background (CMB) radiation was discovered. This light, left over from shortly after the big bang, pervades the universe and carries a record of the first epoch after the birth of the cosmos.....[ More ]

Big Bang Bash:

​Scientists gathered to celebrate the 50th anniversary of the discovery of the CMB—some of the first evidence for the big bang theory—at the laboratory where it was found in 1964.....[ More ]

Penzias and Wilson:

​The famous duo of Arno Penzias (left) and Robert Wilson, the two scientists behind the CMB discovery, reunited at Bell Labs on May 20, 2014, to commemorate their groundbreaking finding half a century later.....[ More ]

Historic Landmark:

​The Horn Antenna that Penzias and Wilson used to make their discovery still stands, although it is no longer in use for astronomy. The instrument was designated as a National Historic Landmark in 1988 for its role in the significant finding, which opened the gateway to modern cosmology.....[ More ]

Pigeon Droppings:

​Penzias and Wilson famously considered the possibility that the radio noise their telescope detected was contamination caused by pigeon droppings on the antenna. “Arno and I got a ladder and went up there and scrubbed off the inside of the horn,” Wilson recalled.....[ More ]


​About 300 scientists, engineers, students and current employees of Bell Labs gathered to celebrate the 50th anniversary of the CMB discovery and see the historic Horn Antenna that enabled the finding.....[ More ]

Big Bang Cake:

The festivities included a cake that read "Big Bang 50th Anniversary," with a photo of the Horn Antenna on it.....[ More ]

Cornucopia Shape:

​The shape of the Horn Antenna blocks stray radio waves from reaching the telescope, accepting only the light on a direct path to the main reflector. This configuration allows it to make sensitive measurements of far-off objects without interference from background radiation.....[ More ]

Project Echo:

​The Holmdel Horn Antenna measures 15 meters long, with a six-meter by six-meter collecting aperture. It was built in 1959 for NASA’s Project Echo, an early test of satellite communication that aimed to transmit and receive radio signals bounced off passive, inflatable satellites placed in Earth orbit.....[ More ]

Radio Astronomy Pioneers:

​Robert Wilson speaks at the anniversary celebration next to a photo of himself and collaborator Arno Penzias standing next to the Horn Antenna during the 1960s, when the pair first detected the confusing signal that turned out to be the CMB radiation.....[ More ]

Feeling Lucky:

​Penzias (left) and Wilson reminisce about their 50-year-old revolutionary finding in front of the telescope that enabled it. “Looking back on all this I feel very lucky,” Wilson says of his role in the discovery.....[ More ]

Experimental Cosmology:

​A plaque from the American Physical Society commemorates the Horn Antenna’s role in uncovering the cosmic microwave background radiation, which “ushered in experimental cosmology” by giving astronomers a piece of evidence that preserves information about the state of the universe just after its birth.....[ More ]

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