![Michael Moloney on X: "Project Echo was the first passive communications satellite experiment, launched in 1960. Now there's over 2,000 communications satellites orbiting Earth! Find out more with @AIPHistory – this diagram Michael Moloney on X: "Project Echo was the first passive communications satellite experiment, launched in 1960. Now there's over 2,000 communications satellites orbiting Earth! Find out more with @AIPHistory – this diagram](https://pbs.twimg.com/media/DocvKD7W4AIp371.jpg)
Michael Moloney on X: "Project Echo was the first passive communications satellite experiment, launched in 1960. Now there's over 2,000 communications satellites orbiting Earth! Find out more with @AIPHistory – this diagram
U.S. Space Command - It's been almost 75 years since humans first bounced a signal off an orbital object and received it back on Earth. In that case, we used the Moon
![Echo 1 Satellite during tests in 1960: 30.5 m in diameter, 0.5 mil Mylar. | Download Scientific Diagram Echo 1 Satellite during tests in 1960: 30.5 m in diameter, 0.5 mil Mylar. | Download Scientific Diagram](https://www.researchgate.net/publication/269300426/figure/fig3/AS:667812607586316@1536230341580/Echo-1-Satellite-during-tests-in-1960-305-m-in-diameter-05-mil-Mylar.png)
Echo 1 Satellite during tests in 1960: 30.5 m in diameter, 0.5 mil Mylar. | Download Scientific Diagram
![Lunar Passenger Sphere 1952, Fig 9 ECHO 1 Satellite, Fig 10 Aries IB,... | Download Scientific Diagram Lunar Passenger Sphere 1952, Fig 9 ECHO 1 Satellite, Fig 10 Aries IB,... | Download Scientific Diagram](https://www.researchgate.net/profile/Andreas-Vogler-2/publication/240632220/figure/fig2/AS:669536810463232@1536641423126/Lunar-Passenger-Sphere-1952-Fig-9-ECHO-1-Satellite-Fig-10-Aries-IB-Fig-11-Bernal-Sphere_Q320.jpg)