A Mercury astronaut used this mechanical device to determine his position relative to the Earth below. A small icon, representing the capsule, tracked his path through space.
This instrument was launched in 1961 on an unmanned test flight. John Glenn and Scott Carpenter, the first Americans to orbit the Earth, carried identical devices on their flights in 1962.
Caption:
A Mercury astronaut used this mechanical device to determine his position relative to the Earth below.
