Survival in Space 
Extreme cold is only one of the hazards 
for astronauts who venture outside a spacecraft 
by Bruce Webbon 
Unprotected in the vacuum of space, 
a human being would survive for only a 
few minutes before swelling up (because 
water vaporized inside the skin would 
not be able to escape as fast as it vapor- 
izes) and becoming freeze-dried. Ac- 
cordingly, without artificial life-support 
and protective systems that emulate the 
earth’s environment, manned space 
flight would not be possible. 
Humans evolved in an atmosphere 
composed primarily of oxygen and nitro- 
gen at a pressure of approximately fif- 
teen pounds per square inch. Although 
it may often seem very hot or very cold, 
the earth’s atmosphere provides a rela- 
tively benign temperature environment 
within an average range of about ± 100 
degrees Fahrenheit. It seldom gets 
colder on Earth than —80° or hotter 
than 130°. By contrast, space lacks a 
true atmosphere and the temperature 
range may go from —460°, an approxi- 
mation of absolute zero, to 300° or 
higher. 
The main requirements for survival in 
space are oxygen at an appropriate pres- 
sure, supplies of food and water, and 
systems to control the humidity, insure a 
comfortable temperature range, remove 
carbon dioxide and other gases, such as 
sulfur dioxide, and handle our solid and 
liquid wastes. Designing equipment to 
satisfy these requirements within the 
smallest spaceship of all — the space- 
suit — is especially difficult. 
The fundamental purpose of the 
spacesuit is to establish around the as- 
tronaut’s body an artificial atmosphere 
containing oxygen. To maintain life and 
to saturate the blood with oxygen, the 
oxygen pressure in that atmosphere 
must be greater than approximately 2.5 
pounds per square inch but there is no 
Astronaut Edwin E. (“Buzz”) Aldrin, 
Jr., dressed for a walk on the moon. 
The photograph was taken during the 
Apollo II mission in 1969 by Neil 
A. Armstrong, the first person to 
step on the moon. 
NASA 
need to have a maximum pressure 
higher than our normal one. The space- 
suit must also protect the astronaut 
from other hazards, such as bombard- 
ment by micrometeoroids. Because the 
intensity of sunlight is much greater 
above the shield of the earth’s atmos- 
phere, the side of the suit facing the sun 
may get very hot, while the other side, 
exposed to deep space, may get very 
cold. The suit must therefore be insu- 
lated to protect the astronaut from these 
temperature extremes. The earth’s at- 
mosphere also guards us from some of 
the high-energy radiation in space; the 
spacesuit must accordingly provide 
some degree of radiation protection. 
Today’s spacesuits evolved from the 
high-altitude flight suits designed in the 
1930s and 1940s to protect airplane 
pilots and balloonists. Those suits, in 
turn, were originally derived from deep- 
sea diving suits. The first experimental 
high-altitude suits were developed in the 
early 1930s by Mark Ridge, an Ameri- 
can aerial stunt man, in conjunction 
with the British physiologist J.B.S. Hal- 
dane. Known for his research on the 
physiological effects of deep-sea diving, 
Haldane worked with Ridge to develop 
a suit that would protect high-altitude 
balloon pilots. In 1933 Ridge tested the 
suit in an altitude chamber at a simu- 
lated altitude of 90,000 feet — approxi- 
mately a mid-stratospheric height. At 
90,000 feet the air is very thin, so this 
suit is considered to be the world’s first 
spacesuit. But Ridge’s dream of using it 
to fly in a high-altitude balloon never 
materialized, and the suit was never 
used again. 
Wiley Post, a well-known test pilot 
and aviation daredevil, also dreamed of 
setting a high-altitude record in his 
Lockheed monoplane, the Winnie Mae. 
Post worked with engineers from the 
B.F. Goodrich Company to develop the 
suit that he used for a series of high- 
altitude flights in 1934 and 1935. But 
Post never got the opportunity of using 
his suit to set an official high-altitude 
record; on a flight with the American 
humorist Will Rogers, in August 1935, 
the plane crashed, killing them both. 
Data provided by these early, pioneer- 
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