credit Photo: NASA
"Form follows function." Nowhere is that dictum more inflexible than in the hostile reaches of outer space. So nothing hews to that dictum more closely than the space suit. Even as it has evolved over NASA’s 50 years to adapt to increasingly sophisticated missions and changing spacecraft technology, the space suit’s central purpose – to maintain a human environment where none exists – remains constant.From the Mercury suit worn by John Glenn during his historic three-orbit flight in 1962 to today’s shuttle and space station rigs, the basic requirements for the space suit have not changed, but the designs have. Here’s a look back at the last piece of technology standing between NASA’s astronauts and oblivion.One Size Fits AllAn astronaut is fitted into his space suit. Because suits are recycled among astronauts, they need to be constantly resized to maintain adequate pressure. This is accomplished using a sizing device developed for NASA by Hubert C. Vykukal.
credit Photo: NASA
Give That Man a Banana =
description Enos the chimp, restrained by wrist tethers and still wearing his space suit, after returning from orbit aboard Mercury Atlas 5 in November 1961. He beat John Glenn into space by two months. 
credit Photo: NASA
The Original ’Right Stuff’ Suit John Glenn in his Project Mercury pressure suit, which he wore when he became the first American to orbit the Earth. Glenn is also the only astronaut to go into space wearing both Mercury and space shuttle suits.
credit Photo: NASA
Looks Like Tinfoil, But Stronger =
description Neil Armstrong, pictured here, would be the first human being to set foot on the moon. But not in this suit. Here, he models a Project Gemini G-2C training suit, designed to be flexible when pressurized. 
credit Photo: NASA
Stepping Out =
description On June 3, 1965, astronaut Ed White became the first American to walk in space. He’s wearing a modified Gemini space suit and is tethered by a lifeline to his Gemini IV capsule. 
credit Photo: NASA
Fly Me to the Moon =
description Engineer Bill Peterson fits test pilot Bob Smyth into an Apollo space suit with a lunar excursion module restraint harness during testing in 1968. Project Apollo put astronauts on the moon, so the suit had to be designed for both lunar conditions and maximum flexibility. 
credit Photo: NASA
Project Apollo =
description America’s first man into space, Alan Shepard, walked on the moon a decade later as commander of Apollo 14. This was the suit he wore, minus helmet and gloves, when he played his famous round of lunar golf. 
credit Photo: NASA
July 20, 1969 =
description The iconic shot: Astronaut Buzz Aldrin is photographed by Apollo 11 commander Neil Armstrong in the Sea of Tranquility. Armstrong is just visible in Aldrin’s face shield. 
credit Photo: NASA
Ready to Bail =
description When the first shuttle flight, STS-1, lifted off on April 12, 1981, astronauts John Young and Robert Crippen wore the ejection escape suit shown here. It’s a modified version of the Air Force’s high-altitude pressure suit. 
credit Photo: NASA
This is the familiar orange launch and entry suit worn by current shuttle crews, nicknamed, appropriately enough, the "pumpkin suit." This is an all-purpose suit designed to cover most contingencies: It includes a helmet with built-in communications gear, a parachute pack and harness, a life raft and life-preserver unit, an oxygen manifold and valves, and survival gear.
credit Photo: NASA
Look, Ma, No … Nothin’ In February 1984, shuttle astronaut Bruce McCandless became the first astronaut to float in space completely untethered to his spacecraft. A jetpack known as the manned maneuvering unit kept McCandless within hailing distance. NASA has since ditched the MMU and are once again secured to the spacecraft, although they do wear a similar device in case of an emergency.
credit Photo: NASA
Looking Ahead =
description An artist’s conception of the future launch and entry suit, left, and a spacewalk suit. Although NASA plans to retire the shuttle in 2010, there are plans to replace it with another vehicle, Orion, by mid-decade, and to return to the moon by 2020. 
credit Photo: Ingrid Barrentine/Wired.com
Adrian Emry, 7, of Moses Lake, Washington, gives a thumbs-up to NASA engineer Bill Welch, who wears a lunar spacesuit concept for use in Project Constellation, the planned U.S. return to the moon.
