constellation space suit, constellation spacesuit, space suit history

Mercury to Constellation: The History of Space Suits

January 12, 2010 12:00 PM
by James Sullivan
As NASA begins testing on three prototype space suits at the Johnson Space Center, findingDulcinea looks at the evolution of space suits and the future of space suit design.

The Constellation Space Suit

The suits, to be tested by NASA astronauts and engineers, were designed as part of the administration’s Constellation program, a plan to update the agency’s technologies and visions for the next era of space exploration.

The Constellation space suit is a two-part system, comprising a “soft” suit for launch, reentry, extravehicular activity and emergency cabin depressurization, and a “hard” suit for planned lunar excursions. David Clark Co., Inc. and ILC Dover, both contractors for Oceaneering International, which was awarded the Constellation space suit design contract in June 2008, are submitting prototypes for testing, along with one prototype developed at the Johnson Space Center.

Suits will be tested for performance in a mockup of the Orion crew vehicle, the Constellation craft being developed to take astronauts back to the moon.

According to NASA, some of the operations the Constellation suits must be fit for are weeklong moon walks and multiple spacewalks during half-year stays in a lunar outpost.

Evolution of the Space Suit

The advent of jet aircraft called for specially designed suits to help pilots cope with the extremes of high altitude, such as low atmospheric pressure and a lack of oxygen. Early suits were composed of a “neoprene rubber-coated fabric that could inflate like a balloon, and a more rigid fabric over the neoprene to restrain the suit and direct the pressure inward on the pilot.” Hoses channeled oxygen directly into the suits, which were designed to pressurize only if cabin pressure failed. 

According to HowStuffWorks, NASA’s Mercury program modified these Navy and Air Force high altitude suits by adding layers of aluminized Mylar, and supplemented them with gloves, lace-up boots and a helmet attached by a collar ring. The Mercury suits, like their predecessors, only pressurized if cabin pressure failed. A primary drawback of the Mercury suits was their rigidity once internally pressurized.

Subsequent suits were designed to provide astronauts with greater mobility, and to allow for spacewalking. Gemini astronaut Ed White II was the first American to spacewalk. New suits had a protective layer of Teflon-coated nylon to shield astronauts from micrometeoroids, along with an umbilical cord to supply oxygen.
In the next era, the challenges that Apollo astronauts would face meant space suits would need considerable innovations. “Not only did the Moon explorers’ spacesuits had to offer protection from jagged rocks and the searing heat of the lunar day, but the suits also had to be flexible enough to permit stooping and bending as Apollo crewmen gathered samples from the Moon, set up scientific data stations at each landing site, and used the lunar rover vehicle, an electric-powered dune buggy, for transportation over the surface of the Moon.” Visit the Encyclopedia Astronautica for a detailed breakdown of the A7L space suits used by the Apollo astronauts.

The current model space suit in use is the EMU, or Extravehicular Mobility Unit. The suit has 13 layers of material, and systems designed to “provide support, mobility and comfort” for the wearer. Whereas older suits had to be customized to fit each individual astronaut, the EMU is composed of a series of different sized pieces that can be assembled to fit any astronaut. HowStuffWorks offers an overview of each of these systems, including the Maximum Absorption Garment (MAG), which collects urine, and the Liquid Cooling and Ventilation Garment (LCVG), which regulates body heat during spacewalks.

Metacafe hosts a short video on the history of space suits.

Reference: Space suits and astronomy

For an in-depth look at the chronology of international space suit development, visit Encyclopedia Astronautica. Click the hyperlinked suit models to see expanded overviews of each, including development and manufacturing information, design enhancements and practical application.

FindingDulcinea’s Astronomy Web Guide highlights the Web’s best resources for learning the basics about astronomy, buying equipment, joining clubs and organizations, finding photos and getting the latest astronomy news.

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