Sign by the Gemini EVA umbilical. It reads
Umbilical Cable: Tether
Astronaut Ed White performed the first U.S. EVA (extravehicular activity),
lasting 20 minutes, from Gemini 4 in 1965. He was secured to
the spacecraft by a 25 ft gold plated umbilical cable which also connected the
suit to the on-board communications and life-support systems. The hand-held
self-maneuvering unit in his right hand helped him control his movements.
The original Gemini 4 post-EVA mission plan called for Ed White to reopen the
spacecraft's hatch after disconnecting the umbilical and re-connecting his suit
directly to the spacecraft's environmental control system to jettison the EVA
equipment, but since he encountered difficulties closing the hatch after his
EVA, the jettison procedure was scrubbed.