For this week’s science-related travel image, we’re going back to the New Mexico Museum of Space History in Alamagordo. The picture is of a life-size model of the Echo II satellite in its launch canister:
Launched from Vandenberg Air Force Base in 1964, Echo II inflated into a large, reflective balloon once in orbit. Like its predecessor Echo I, Echo II was used for passive communication experiments conducted by bouncing radio signals from one ground station to another. Basically, the electronic technology of the time proved hard to miniaturize, and passive satellites were thought to have potential as a “stopgap” communication technology while work on more sophisticated electronics was pursued. 41 meters in diameter fully inflated, Echo II was also used for atmospheric drag and air density experiments.
The Echo satellites also made excellent targets for global geometric geodesy, and in the end, this may well have proven their most effective use. While NASA abandoned passive communications systems in favor of active satellites after Echo II, the U.S. military found its own uses for the Echo satellites. These large, bright satellites indirectly provided the data needed to accurately locate the city of Moscow — a handy thing to have when you wish to target ICBMs at it.