For extravehicular activity (EVA) more complex space suits are worn, featuring a portable life support system.
A self-contained oxygen supply and environmental control system is frequently employed to allow complete freedom of movement, independent of the spacecraft.
[citation needed] During exploration of the Moon or Mars, there will be the potential for lunar or Martian dust to be retained on the space suit.
When the space suit is removed on return to the spacecraft, there will be the potential for the dust to contaminate surfaces and increase the risks of inhalation and skin exposure.
This procedure purges the body of dissolved nitrogen, so as to avoid decompression sickness due to rapid depressurization from a nitrogen-containing atmosphere.
[1] The human body can briefly survive the hard vacuum of space unprotected,[3] despite contrary depictions in some popular science fiction.
[4] In space, there are highly energized subatomic particles that can cause radiation damage by disrupting essential biological processes.
[1][6] The most immediate hazard is in attempting to hold one's breath during explosive decompression as the expansion of gas can damage the lungs by overexpansion rupture.
However, because a minimum internal pressure is dictated by life support requirements, the only means of further reducing work is to minimize the change in volume.
Hard suits joints use ball bearings and wedge-ring segments similar to an adjustable elbow of a stove pipe to allow a wide range of movement with the arms and legs.
[citation needed] ILC Dover's I-Suit replaces the HUT with a fabric soft upper torso to save weight, restricting the use of hard components to the joint bearings, helmet, waist seal, and rear entry hatch.
Sweat evaporates readily in vacuum and may desublime or deposit on objects nearby: optics, sensors, the astronaut's visor, and other surfaces.
[8] The Mercury IVA, the first U.S. space suit design, included lights at the tips of the gloves in order to provide visual aid.
As the need for extravehicular activity grew, suits such as the Apollo A7L included gloves made of a metal fabric called Chromel-r in order to prevent punctures.
[NASA, ILC Dover Inc. 1] This allows for cheaper, more accurate production, as well as increased detail in joint mobility and flexibility.
[25] A mannequin, called "Starman" (after David Bowie's song of the same name), wore the SpaceX space suit during the maiden launch of the Falcon Heavy in February 2018.
[28] The suit, which is suitable for vacuum, offers protection against cabin depressurization through a single tether at the astronaut's thigh that feeds air and electronic connections.
[29] In 2018, NASA commercial crew astronauts Bob Behnken, and Doug Hurley tested the spacesuit inside the Dragon 2 spacecraft in order to familiarize themselves with the suit.
It is more mobile, includes new thermal insulation fabrics, and materials used Falcon’s interstage and Crew Dragon’s external unpressurized trunk.
The prototype arm segment is designed to be evaluated in the Space Systems Laboratory glovebox to compare mobility to traditional soft suits.
The suit is designed to study contamination vectors in planetary exploration analogue environments and create limitations depending on the pressure regime chosen for a simulation.
[50] In 2024, at the International Astronautical Congress in Milan, Italy, Axiom Space and Prada showed the results of an ongoing collaboration to develop a spacesuit for NASA's Artemis III mission.
[34] Bio-Suit is a space activity suit under development at the Massachusetts Institute of Technology, which as of 2006[update] consisted of several lower leg prototypes.
FFD has built a total of 7 IVA space suit (2016) assemblies for various institutions and customers since founding, and has conducted high fidelity human testing in simulators, aircraft, microgravity, and hypobaric chambers.
The I-Suit is a space suit prototype also constructed by ILC Dover, which incorporates several design improvements over the EMU, including a weight-saving soft upper torso.
Both the Mark III and the I-Suit have taken part in NASA's annual Desert Research and Technology Studies (D-RATS) field trials, during which suit occupants interact with one another, and with rovers and other equipment.
[59] The suit has components which could be 3D printed during missions to a range of specifications, to fit different individuals or changing mobility requirements.
Suitports require less mass and volume than airlocks, provide dust mitigation, and prevent cross-contamination of the inside and outside environments.
Patents for suitport designs were filed in 1996 by Philip Culbertson Jr. of NASA's Ames Research Center and in 2003 by Joerg Boettcher, Stephen Ransom, and Frank Steinsiek.
Later comic book series such as Buck Rogers (1930s) and Dan Dare (1950s) also featured their own takes on space suit design.