Space suits are one of the often-overlooked technologies that humans need to live in and explore space.    They allow us to take our environment with us, protecting us from extreme temperatures, bombardment by micro-meteorites, and of course the total lack of atmospheric pressure and oxygen in space.   They’ve come to be amazingly complex examples of modern engineering, as well as symbols of humanity’s future. And as you might expect, they’ve evolved a lot over the past hundred years.    Yes, I said A HUNDRED YEARS.   [Intro]   Space suits date back to long before we ever hoped to reach the stars -- back to the early days of flight itself.    As daredevil airplane pilots, and even balloonists, soared to ever-greater heights a century ago, they started to experiment with simple pressure suits.    Because they learned quickly that the higher you go, the less dense the air becomes.   So in order to reach for the sky, and eventually the stars, we had to devise ways to keep ourselves surrounded with the equivalent of atmospheric pressure, and provide us with breathable air.   The first attempt was patented in 1918. Inventor Fred Sample’s design included a helmet bolted to what was basically a pair of pressurized coveralls, with a tube leading to an air tank.   In the 1930s, these glorified onesies were refined and perfected by aviator Wiley Post.   Post was the first pilot to fly around the world solo, the record-holder for flying at 40,000 feet, and the discoverer of the jet stream.    He commissioned a suit made of rubberized parachute fabric with an aluminum helmet, later developing this into a more complex get-up that featured several layers, including long underwear, a rubber air-pressure suit, and an outer suit made of cloth coated with latex.    This sci-fi worthy suit was bizarre looking, but it got the job done.   While standard atmospheric pressure at sea level is said to be 1 atmosphere, Post’s suit managed to create an environment of 0.8 atmosphere, or the equivalent of one and a half kilometers above sea level.   And that was fine for your run-of-the-mill death-defying barnstorming -- but by the time NASA was developing suits for the Mercury astronauts in the 1960s, they knew they had to offer A LOT more protection.    When Alan Shepard, one of the Mercury Seven, became the second person to travel into space, he wore a modified version of the US Navy high-altitude pressure suit. It was made of some brand-new materials like the synthetic rubber-like fabric known as neoprene, along with nylon coated with aluminum to protect against radiation.    Then came the next giant leap for mankind: EVAs, or Extravehicular Activities, such as spacewalks and walking on the moon!    For this, NASA had to develop a whole new class of suits to protect astronauts from space itself. After all, temperatures can range from -290 degrees to 310 degrees Fahrenheit, and micrometeorites, which usually weigh less than a gram, can be traveling up to 10 km per second or 22,500 mph.    And the suits used in the Apollo missions were truly masterpieces of engineering. Custom-made for each astronaut, they featured a water-cooled undergarment, followed by an inflatable layer to create air pressure around the body, and an outer envelope including two layers of Teflon that provided protection from the environment.   By the time the Shuttle and Space Station years came around, astronauts were spending a lot more time in space. They needed two types of suits on every mission: basic pressurized Advanced Crew Escape Suits for takeoff and re-entry, and Extravehicular Mobility Units for extravehicular fun.    Not to be outdone by their predecessors, these suits contain 14 layers of material, ranging from mylar and neoprene to urethane-coated nylon, spandex, and stainless steel. They’re still in use today!   So what’s the future of space couture?   Well, today’s suits allow only limited motion at built-in joints, so NASA designers say its next space suit will focus on better mobility.    In 2014 the space agency unveiled prototypes of a new suit it calls the Z-2. Slightly less bulky than current models, it features segmented pleats at all of the joints, as well as luminescent wiring and patches built into the exterior, which may not only allow crew members to identify each other in darkness, but they also look TOTALLY BOSS.   The Z-2 probably won’t be used in any actual missions, though -- NASA says it plans to use it in ground tests and simulations to help design the full, multi-layer version.   Some other groups are dreaming up radically different designs, such as the concept of the Space Activity Suit tested at MIT. These already look like the fashion statement of the millennium - one that the next generation of space explorers will wear to nearby asteroids, Mars, and points beyond.    Thanks for watching this episode of SciShow Space! And thanks to all of our Subbable subscribers who make this channel possible! To learn how YOU can support SciShow Space, go to Subbable.com/scishow to learn more.   And if you have questions or ideas for an episode you’d like to see, you can find us on Facebook and Twitter and in the comments below, and if you want to keep getting smarter with us, just go to YouTube.com/SciShowSpace and subscribe!