blueprint, April 19, 1963

The Mercury spacesuit, described by NASA as an “aluminum-coated nylon-rubber creation,” was a wearable environment that protected the astronauts from the extreme conditions of space. Without protection, a human would die from lack of oxygen and suffer the effects of little or no air pressure. Contrary to popular belief, humans would not explode or instantly freeze; blood would not instantly boil.

Evolved from a pressure suit used by Navy pilots flying at extreme altitudes, the suits provided oxygen to the astronauts, kept them in carefully regulated temperatures, and could be pressurized in case the spacecraft’s air pressure system failed, which it never did. The Mercury suits were worn “soft,” or unpressurized. Throughout the years of the Mercury program, the latest technological advances were incorporated into the design of the suits.

Oxygen, which came in through the torso, flowed throughout the suit to cool it, then circulated in the helmet for breathing. Exhaled air escaped through a special vent in the helmet.  The Mercury suits, intended for relatively short missions, did not originally provide the astronauts with a waste relief system; urine collection bags were incorporated after the first manned mission.