Inflation Testing an Early Satellite, 28 June 1961

Photo: National Aeronautics and Space Administration
National Archives and Records Administration
Still Picture Branch - College Park, Maryland

This satellite’s name is Echo Two and it had a diameter of a 135 feet, or 40 meters. The satellite, actually a balloon, was made of Mylar that was coated with aluminum on the inside. There were two satellites in the Echo series and the only communication capabilities that they had was to reflect radio waves from the aluminum surface back to earth. They were launched into orbits that caused them to circle the earth about once every two hours at an altitude of about 1000 miles, or 1600 kilometers. They were visible from earth in the evenings and looked like fast moving stars. Echo One was launched on 12 August 1960. It was 100 feet, or 30 meters, in diameter and remained in orbit for almost eight years while Echo Two was launched on 24 January 1964 and remained in orbit for about five years.

The Echo series were experimental satellites and their purpose was for testing the feasibility of using satellites to relay telephone, data and other communication signals. Echo Two was the first instance where cooperation between the United States and the USSR in a space mission occurred and it relayed a signal from an observatory in Manchester, England to Zimenki Observatory near Gorky, Russia. Æ