1969

Space Suit

While Soviet cosmonaut Yuri Gagarin’s space suit, the SK-1, was the first to be worn in orbit, it was not meant for the challenges of a moon landing. The environment on the moon is about as harsh as it gets: a hard vacuum, intense solar radiation, and abrasive moon dust are three of the biggest challenges. Engineers working on the space suits to be worn during moon landings were faced with a unique challenge: how to produce a suit that would allow a human being to walk freely in these conditions. This isn’t ordinary engineering—this is mission-critical engineering. The suit must perform flawlessly or someone will die. And the suit also has to be comfortable and flexible enough for astronauts to use it for up to eight hours one day, and then put it on and use it again the next day.

The suit itself is a remarkable, multilayer, fabric spaceship. This ship happens to be formed in the shape of a human and is designed for short-duration trips, but it is a spaceship nonetheless. The astronaut wears an undergarment laced with water-filled tubes to provide cooling. Then the suit itself starts with a sealed, rubberlike balloon made of neoprene-coated nylon. This layer holds in the pressurized atmosphere. More than a dozen layers of nylon, Mylar, Dacron, Kapton and Teflon-coated glass fibers provide protection from heat, cold, abrasion, puncture, and moon dust.

The backpack, called the PLSS or Primary Life Support System, provided the atmosphere and cooling, along with power and radio links. Oxygen tanks refreshed the oxygen that the astronauts consumed, and a CO2 scrubber based on lithium hydroxide removed the carbon dioxide exhaled. A water reservoir provided for cooling.

There was also a backup system should the primary system fail. A separate oxygen tank could flow oxygen into the suit and vent it, keeping the astronaut oxygenated and cool. This system was simple and worked for about thirty minutes in an emergency.

The engineering done for the spacesuit created a highly reliable system that worked without failure on multiple missions. It is a true testament to engineering excellence.

SEE ALSO Radio Station (1920), Apollo 1 (1967), Lunar Rover (1971), International Space Station (1998).

American astronauts were fitted with suits that could stand conditions on the surface of the moon. Yuri Gagarin’s suit was made to handle flight in space, but not a lunar landing.