Echo 1

Echo 1 was the world's first communication satellite. Essentially just a big, mylar balloon inflated in orbit, radio waves bounced off of the surface of the satellite to the next ground station. There's a famous picture of an inflated Echo satellite. Oddly enough, this particular photo identifies the satellite's diameter as both 135 feet (in the caption, which is representative of Echo 2) and 100 feet (in the description, which is representative of Echo 1); the date on the photo itself is several weeks before the Echo 1 launch.

A recorded message from President Eisenhower was bounced off Echo 1 and broadcast across the country. It began, "This is President Eisenhower speaking. It is a great personal satisfaction to participate in this first experiment in communications." The History Channel has an audio recording of the full message.

The Jet Propulsion Laboratory formerly had a "Quicklook" at the Echo 1, 1A, and 2 satellites, and Chapter 6 of Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo has a much more in-depth account of the Echo program. Langley also has a shorter Project Echo page.

I have a page on Echo satellite launch adapters which compares the Echo 1 launch adapter with those of later Echo-type satellites.

This is Echo 1 flight satellite and canister is NASM collections inventory number A20030090000.