Moon relayIn 1954, the sound of a human voice was, for the first time ever, transmitted beyond the ionosphere and returned to Earth after reflecting off the moon. James H. Trexler, an engineer in the Radio Countermeasures Branch at the Naval Research Laboratory (NRL), spoke carefully into a microphone at the laboratory's Stump Neck radio antenna facility in Maryland. Two and a half seconds later, his words speeded back to him at Stump Neck, after traveling 500,000 miles via an Earth-Moon circuit. The objective of the Communication Moon Relay project was to add another option for the Navy's secure global communications technologies that could reduce the vulnerability of ionospheric storms cutting off radio transmissions to the U.S. fleet.[Image: Early notebook entry by James H. Trexler, 28 Jan 1945, showing calculations for a long-distance communications link via the Moon.] |
