Editing Project Echo (section)

== See also ==
{{Portal|Spaceflight}}
* [[AO-51]], AMSAT-[[OSCAR]] 51 (also known as Phase 2E, or '''ECHO''') – an amateur radio communications satellite launched in 2004
* [[Courier 1B]] – world's first active repeater satellite, launched in 1960
* [[List of communications satellite firsts]]
* [[PAGEOS]] – a similar balloon satellite project
* [[Project SCORE]] – world's first communications satellite, launched in 1958
* [[Telstar]] – first active, direct relay communications satellite, launched in 1962
* [[TransHab]], a subsequent expandable spacecraft technology project pursued by NASA
* [[U.S. space exploration history on U.S. stamps]]
* [[Norman L. Crabill]]