On This Day in History - August 12, 1960
Echo 1 communication satellite in Weeksville, NC, 1960. Credit: NASA
On August 12, 1960 NASA launched the world's first successful communications satellite from Cape Canaveral, Florida, the Echo 1. Earlier that year in May 1960, a similar but unsuccessful attempt by NASA to launch a nearly identical satellite failed to reach orbit. This first attempt was the maiden voyage of the Thor-Delta launch vehicle where attitude control jets on the Delta stage failed to ignite, sending the payload into the Atlantic Ocean instead of into orbit.
Echo 1 was designed as a passive communications reflector to relay telephone, radio, and television signals between two points on Earth. It was the first of its kind, providing the potential to massively expand communications worldwide.
Static inflation test of Echo 1 communication satellite in Weeksville, NC, 1960. Credit: NASA
Measuring 100 feet in diameter, the Echo 1 satellite was based on a balloon design and made of a 31,416 square foot sheet of mylar polyester film .0127 mm thick. The sheet was covered with 4 pounds of reflective aluminum coating, and the whole spacecraft weighed 132 pounds. Nicknamed a "satelloon," it was launched into orbit and inflated once in space. Forty thousand pounds of air was required to inflate the sphere on the ground, meanwhile in orbit it only required several pounds of gas to keep it inflated.
A few hours after its launch, Echo 1 relayed its first message, reflecting a radio signal from California to Bell Labs in New Jersey. The message was an address from President Eisenhower in which he said, "The satellite balloon, which has reflected these words, may be used freely by any nation for similar experiments in its own interest." Echo 1 stayed in orbit for eight years, and was visible to the naked eye over the entire planet. It's considered to have been seen by more people than any other manmade object in space. NASA released daily schedules telling when and where the sphere could be seen overhead. Amateur ham radio operators were able to bounce signals off of it.
Holmdel Horn Antenna located in Holmdel Township, NJ, 1962. Credit: NASA
The launch of Echo 1 laid the groundwork for modern satellite communications. In order to communicate with Echo 1, Bell labs created a 50 foot, horn shaped antenna. While calibrating the antenna, radio astronomers detected cosmic microwave background radiation, the first solid evidence of the Big Bang, for which they won the Nobel Prize. The Echo 1 also proved remarkably durable, surviving a meteor shower. Still, it proved susceptible to sunlight, enough to push it back into Earth's atmosphere where it burned up on re-entry on May 24, 1968. NASA continued with Project Echo, launching Echo 2, a similar but larger satellite balloon, in January 1964. But ultimately NASA chose to use satellites that could actively transmit data, rather than passively reflect signals.