ROOT / WORLD PROJECTS / SPACESUITS // DECODED EVA · HUMAN SPACEFLIGHT
Spacesuits // Decoded

A spacecraft
you can wear.

A spacesuit is a personal, human-shaped spacecraft — it supplies oxygen, holds pressure against the vacuum, regulates temperature from +120°C sunlight to −150°C shade, stops micrometeoroids and radiation, and still lets an astronaut bend, grip and walk. This is every major suit ever flown, from Mercury to the Moon suits being built for Artemis.

1961
First suit in space (Gagarin · SK-1)
4.3 psi
Typical EVA suit pressure (pure O₂)
8+ hrs
EMU life-support endurance
2027
AxEMU · next Moon-surface suit
// the two jobs a suit does

IVA vs. EVA.

Every suit is built for one of two roles — and the difference drives almost every design choice.

IVA — Intravehicular ("launch & entry")

Worn inside the vehicle during launch, re-entry and emergencies. Lighter and more flexible; it only needs to hold pressure if the cabin depressurizes. Examples: the Sokol, SpaceX's Crew Dragon suit, Orion's OCSS, the Shuttle's orange ACES "pumpkin suit."

EVA — Extravehicular ("spacewalk")

A self-contained spacecraft for working in vacuum. It carries its own oxygen, CO₂ scrubbing, cooling, power and comms in a backpack (the PLSS), plus rigid joints and layered protection. Examples: Apollo A7L, the ISS EMU, Russia's Orlan, China's Feitian, the Axiom AxEMU.

// anatomy

Inside an EVA suit

A modern spacewalk suit is a dozen systems layered into a garment.

Pressure garment

A bladder that holds 4.3 psi of pure oxygen against the vacuum, restrained by a fabric layer so it doesn't balloon rigid.

Liquid cooling garment

Long underwear threaded with 90 m of water tubing that carries away body heat — without it, an astronaut would overheat in minutes.

PLSS (life-support backpack)

Oxygen tanks, a CO₂-scrubbing bed, a fan, a water sublimator for cooling, batteries and radios — 8+ hours of self-contained life.

Micrometeoroid layers

Multiple layers of Kevlar, Mylar and Nomex/aramid stop debris, insulate against ±150°C swings, and block radiation.

Helmet & visor

A polycarbonate bubble with a gold-coated sun visor; modern designs add lights, cameras and heads-up displays.

Joints & bearings

Rolling-convolute and bearing joints at shoulders, elbows, wrists, hips and ankles let a pressurized suit actually move.

// the index

Every major suit, spec'd

From the first pressure suits to the vehicles being built for the Moon and Mars. Pressures and masses are nominal published figures.

SuitProgram · eraTypePressureNotes
SK-1Vostok · USSR 1961IVA5.8 psiYuri Gagarin's suit — the first worn in space. Orange, with an inflatable neck ring.
Navy Mark IVMercury · US 1961IVA3.7 psiModified high-altitude Navy pressure suit; silver, worn but never pressurized in flight.
BerkutVoskhod · USSR 1965EVA5.8 psiLeonov's suit for the first-ever spacewalk; ballooned so stiff he had to bleed pressure to re-enter.
Gemini G4CGemini · US 1965IVA/EVA3.7 psiFirst US EVA suit (Ed White). Layered nylon and Nomex over a pressure bladder.
Apollo A7L / A7LBApollo · US 1969EVA3.7 psiThe Moon suit. 21 layers, custom-tailored, with the PLSS backpack — walked on the lunar surface.
Orlan (to MKS)Salyut→ISS · USSR/Russia 1977–EVA5.8 psiRear-entry "you climb in" design; semi-rigid torso, one-size-adjustable. Still used on the ISS.
Sokol KV-2Soyuz · USSR/Russia 1973–IVA5.8 psiThe white launch/entry suit worn in Soyuz — a rescue suit for cabin depressurization.
Shuttle EMUShuttle→ISS · US 1981–EVA4.3 psiModular hard-upper-torso EVA suit; the current NASA spacewalk suit, now decades old.
ACES ("pumpkin")Shuttle · US 1994–2011IVA3.5 psiThe orange full-pressure launch/entry suit with parachute and survival gear.
FeitianShenzhou · China 2008–EVA5.8 psiChina's Orlan-derived spacewalk suit; first used on Shenzhou 7.
SpaceX IVA suitCrew Dragon · 2020–IVAflight-pressureSleek one-piece launch/entry suit; 3D-printed helmet, touchscreen-friendly gloves.
Orion OCSSArtemis · US 2022–IVA4.3 psiOrion Crew Survival System suit — an improved orange launch/entry suit for deep-space missions.
SpaceX EVA suitPolaris Dawn · 2024EVA5 psiEnabled the first commercial spacewalk (Sep 12, 2024, 700 km). Helmet HUD + camera, new thermal textiles.
Axiom AxEMUArtemis III · US 2027 (planned)EVA4.3 psiNext Moon-surface suit, with Prada on materials. Kneeling mobility, 850+ hrs crewed testing; in production.
// deep dive

Four landmark suits

◊ 1969 · the Moon suit

Apollo A7L

Hand-built by ILC Dover (a company with roots in bras and girdles, whose seamstresses sewed each suit to a tolerance of 1/64"). Twenty-one layers wrapped a rubber-coated nylon bladder; the PLSS backpack gave 7 hours of oxygen, cooling and comms. The A7LB added a neck and waist joint so Apollo 15–17 astronauts could sit in the lunar rover. It remains the only garment ever worn to walk on another world.

◊ 1981–now · the workhorse

The Shuttle / ISS EMU

The Extravehicular Mobility Unit is a modular suit built around a rigid fiberglass hard-upper-torso, mixing sizes to fit different astronauts. At 4.3 psi of pure oxygen, crews "pre-breathe" to purge nitrogen and avoid the bends. Its water-sublimator cooling and CO₂ scrubbing sustain 8+ hour spacewalks — but the fleet is 40+ years old, and water-in-helmet incidents have driven the urgent search for a replacement.

◊ 2024 · the first commercial spacewalk

SpaceX EVA suit

Developed in 2.5 years, SpaceX's EVA suit made history on Sept 12, 2024 when Jared Isaacman and Sarah Gillis stepped into vacuum at 700 km during Polaris Dawn — the first spacewalk by private astronauts. It adds mobility, a helmet heads-up display and camera, and new thermal fabrics, reusing materials from Falcon's interstage and Dragon's trunk. It's the first step toward mass-producible suits for Mars.

◊ 2027 · back to the Moon

Axiom AxEMU

The suit Artemis III astronauts will wear on the lunar south pole, built by Axiom Space with Prada advising on materials. Designed for far greater mobility than Apollo — astronauts can kneel and work close to the surface — and fitting a wide range of body types. By 2026 it had passed 850+ hours of crewed pressurized testing and entered production, with first flight units being assembled for a landing now targeted around 2027.

// research · datasets

Where the full records live

Authoritative public repositories with technical drawings, specs and 3D models for spacesuit research.

NASA NTRS

The NASA Technical Reports Server holds hundreds of reports, drawings and specifications for every NASA suit.

NASA 3D Resources

Free, public-domain 3D models — including the Advanced Crew Escape Suit — viewable in our 3D dashboard.

Smithsonian NASM

The National Air and Space Museum's conservation project has digitized and 3D-scanned historic flown suits.

Manufacturer disclosures

ILC Dover, Collins Aerospace, Axiom Space, SpaceX and Roscosmos publish suit specs and imagery.

◊ Sources: NASA (spacesuit history & AxEMU announcements) · Axiom Space · Polaris Program / SpaceX · Scientific American · Space.com · NPR. Specs are nominal published values; pressures vary by operating mode.