Pictures: What's Inside a Space Suit? X-Rays Reveal All

Space Suit, Stripped
Images courtesy Mark Avino and Roland H. Cunningham, SI
An advanced experimental space suit made by the Air Research Corporation in 1968 is seen via x-ray (right), which reveals a series of aluminum coils and tubes inside.
This x-ray, one of several on display at the Smithsonian's National Air and Space Museum in Washington, D.C., helps paint a fuller portrait of the outfits astronauts wear while outside their shuttles to keep themselves alive and protect against the vacuum of space.
The x-rays are part of a larger exhibit called "Suited for Space," which traces the evolution of space suits over the past 60 years through photos, x-rays, and artifacts. (Related: "Photos: Space Suit Evolution Since First NASA Flight.")
Cathleen Lewis, a historian and curator of International Space Programs at the museum, explained that the coils located where elbows and knees would be were designed to help astronauts move their joints in their pressurized suits in outer space.
"The shoulder area allows astronauts to localize air displacement and restrain the pressurization," she said. "The joints were designed to automatically localize the displacement of air."
In other words, if an astronaut lifted his or her arm in space without these specialized joints, the arm would balloon up—making it impossible to do work.
The traveling exhibit will remain in Washington, D.C., through December 1, when it will continue to stops in Tampa, Philadelphia, and Seattle.
—Melody Kramer
Published July 29, 2013
In a Vacuum
Image courtesy Mark Avino and Roland H. Cunningham, SI
The space suit above was built as a demonstration suit for testing in a vacuum chamber at NASA's Ames Research Center.
The chamber was designed to simulate the environment in outer space. Astronauts would get into their suits, hook themselves up to oxygen, and then go into the vacuum chamber, which simulated the environment at an altitude of 400,000 feet (121 kilometers).
"They were then asked to do repetitive and somewhat mind-numbing tasks, like walking up and down on a crate, so that technicians could check their suits," said Lewis.
Though the space program was relatively young in the late 1960s when this suit was developed, it was building off of almost 20 years of experience with hardened suit designs. They were originally made for the U.S. Air Force in the early 1950s, back when the Air Force used vacuum tubes in aircraft. (See pictures of early U.S. spaceflight.)
"But many of the vacuum tubes were failing," said Lewis. "And they needed to figure out why."
Enter Litton Industries. The large defense contractor, which was bought by Northrop Grumman Corporation in 2001, designed a vacuum chamber to test why the vacuum tubes were failing. But to do that, they needed to design a suit for a technician to wear while inside the vacuum chamber.
"The Air Force was intrigued," said Lewis. "Even after they discontinued the use of vacuum tubes in aircraft, they continued to fund Litton's suits. And when NASA formed [in 1958], they took over much of the research in suit development from the Air Force."
In the years that followed, hundreds of people worked on space suits: Engineers designed the suits, technicians tested them, manufacturers created the parts, and then other folks assembled the final product.
"You can't tell by the x-ray, but some of the components are hand-sewn," said Lewis.
Published July 29, 2013
Heads Up
Image courtesy Mark Avino and Roland H. Cunningham, SI
The 1964 helmet design (pictured) does far more than protect the head.
Designed to fit on several suits, the helmet has ball bearings in the neck ring—visible on the x-ray—that gave astronauts mobility and allowed them to move their heads left and right.
"This helmet forms a seal to keep air in, but it also supplies communication wires and an oxygen supply," said Lewis. She pointed to the darker components in the middle of the helmet, noting, "All of those are the parts that supply oxygen."
Not visible on the x-ray? The defogger, which was typically sprayed on the front of the helmet to prevent it from getting misty in space. Now it's a complex and specially designed chemical, but back in the day, "they used dishwashing detergent," revealed Lewis.
(Also see "New Skintight Spacesuit Design Revealed.")
Published July 29, 2013
Cold Shoulder
Image courtesy Mark Avino and Roland H. Cunningham, SI
The art of designing a proper arm for a space suit was a difficult one, in part because the suit had to remain pressurized.
"Under pressurization, a suit was just hard to move around in," said Lewis. "The art was making it an easy-to-move joint."
Engineers localized air displacement so that bending an arm wouldn't cause, say, the other arm to move straight out—like twisting one part of a balloon makes it bulge somewhere else.
"They were really looking to improve mobility in the arms after the Mercury and Gemini missions," said Lewis. "In order for astronauts to do meaningful work, they have to have their hands available."
(See a space exploration time line.)
Published July 29, 2013
Space Boot
Image courtesy Mark Avino and Roland H. Cunningham, SI
This space suit overshoe, as it's called, was designed to fit over an astronaut's shoes while the astronaut was walking on the moon.
"They were made in order to better insulate the astronaut's feet," said Lewis.
On the bottom of the shoe is silicon; on the top, a material made of chromium and stainless steel. These materials were used as an extra layer of protection on boots and gloves, in case the astronauts touched or stepped on anything sharp on the lunar surface.
Although they were used on every Apollo mission, only one pair of space overshoes—the one pictured above and its mate, from Apollo 17—made it back from the moon.
The others were left on the lunar surface because of weight restrictions on the return mission.
Published July 29, 2013
Helping Hand
Image courtesy Mark Avino and Roland H. Cunningham, SI
Gloves are the most difficult part of a space suit to make. And with good reason.
"If an astronaut's going out into space to do something meaningful, he or she needs dexterity and a sense of touch to work with tools," said Lewis.
"They also need to be protected as well—so it's a careful balance."
The glove pictured above was part of the Apollo mission. It may look fingerless, but x-rays are deceiving: The fingertips were made of silicon, which doesn't absorb any radiation, so they don't show on x-rays. And that ring located just above the wrist? It's to prevent the glove from flying away when it's inflated.
"You have to keep it tied to the suit, but you have to be careful because you don't want nerve-compression problems," said Lewis.
"But all of the astronauts complained about the gloves. They still complain about the gloves."
(Related:"Astronauts' Fingernails Falling Off Due to Glove Design.")
Published July 29, 2013