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How the U.S. Accidentally Nuked Its Own Communications Satellite

Fifty years ago AT&T launched Telstar 1, the first commercial communications satellite, right into the middle of a radiation storm produced by a nuclear test
Starfish Prime, Starfish Prime Explosion



Los Alamos National Laboratory

In 1962 a small spherical satellite weighing about 77 kilograms was launched from Cape Canaveral.  Its name was Telstar 1, and it was the first commercial telecommunications satellite—the first of a long line that have led to today's digitally connected world, where television programs and other media are easily accessible at locations across the globe.

By the following February, however, Telstar 1 had been completely fried by energetic electrons from a U.S. high-altitude nuclear test.

Walter Brown, a Bell Laboratories engineer who worked on the project, recalls Telstar 1’s triumphs and untimely demise. Currently a professor of materials science and engineering at Lehigh University in Pennsylvania, he says it was his job to “examine how radiation in space affects solar cells and semiconductors.” He got rather more than he bargained for.

The day before launch, the U.S. had set off a nuclear explosion at an altitude of 400 kilometers just southwest of Johnston Island in the Pacific Ocean. The test, known as Starfish Prime, released the energy equivalent of 1.4 megatons (million tons) of TNT—creating a huge electromagnetic pulse that produced spectacular aurora over the Pacific.

"The people who set off the nuclear explosion were totally surprised by the huge number of high energy electrons that were released," Brown says. "They had no idea this would be the case until we started seeing this huge flux, a hundred times what was predicted."

The satellite unwittingly became an experiment to analyze the aftermath of a nuclear blast on electronic equipment. "We learned a lot about radiation damage from Telstar 1," he says. "Initially, Telstar 1 couldn't be turned on, some transistors had failed. But the electronics engineers figured a way around that and got it working."

Their efforts bought enough time for the satellite to prove its worth. On July 11, 1962, a day after launch, Telstar 1 relayed the television transmission of an American flag, located outside a base station in Andover, Maine, to a station in Pleumeur-Bodou, France. Brown remembers what happened at the Andover station when the satellite was turned on and radio transmission commenced: “The project leader Eugene O’Neill whooped and gave thumbs up. And soon everyone was whooping and giving thumbs-up."

On July 23, 1962, Telstar 1 relayed a public broadcast featuring Walter Cronkite, a baseball game, and segments of a news conference by President Kennedy. That evening, it transmitted the first non-cable phone call across the Atlantic.*

Telstar 1 vindicated the vision of John Robinson Pierce, a famous Bell Labs engineer who had calculated that 25 satellites placed in suitable orbits around the Earth could provide continuous communication between any two points on the globe by bouncing signals. The first test of his idea had been the Echo 1 satellite, a giant 30-meter-diameter balloon coated with a metallized film, which NASA launched in 1960. Known as a passive communications satellite because it carried no electronics but rather acted as a giant signal reflector, it was used by Bell Labs engineers to successfully bounce telephone, radio and television signals off it. Telstar 1 went a step further. It had its own power source--solar cells that generated approximately 14 watts of power, and a transponder to receive and retransmit television signals or telephone calls.

Its success against the odds inspired a generation of scientists and engineers. Louis Lanzerotti, a physicist at New Jersey Institute of Technology who spent many years at Bell Labs and worked on space missions such as Voyager, Ulysses and Galileo, was a graduate student in nuclear physics at Harvard University when Telstar 1 went into orbit. "The graduate students in the cyclotron lab talked about it," he recalls. "We talked about sending signals across the Atlantic."

But the engineers could stave off the inevitable only so long: In February 1963 accumulating radiation damage finally caused Telstar 1's transistors to fail irreparably. Fortunately, the energized electrons had dissipated when NASA launched Telstar 2 a year later. By that time both the U.S. and Soviet Union had ceased high-altitude nuclear testing.

*Clarification (7/11/12): This sentence was changed after posting. It originally stated that the first transatlantic telephone call was made via Telstar 1.

 

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