• You will become unconscious within 15 seconds because there is no oxygen

• Your blood and body fluids will boil and then freeze because there is little or no air pressure

• Your skin, heart, and other internal organs will expand because of the boiling fluids

Why do Astronauts need Space Suits?

This photo shows what will happento fluids in the microgravity

of space

Why do Astronauts need Space Suits?

• You will be exposed to extreme changes in temperature: 248°F (120°C) in the sunlight and -148°F (-100°C) in the shade

• You will be exposed to various types of radiation such as solar wind (charged particles emitted from the sun) and cosmic rays

• Inside the spacecraft the atmosphere can be controlled so that special clothing is not needed

• There is no atmospheric pressure and oxygen in space to sustain life so to explore and work in space human beings must take their environment with them

An astronaut inside the ISS

Why do Astronauts need Space Suits?

• Supply oxygen• Protect the body from

bombardment from micrometeoroids

• Insulate the wearer from the temperature extremes of space

• Remove heat and moisture generated by sweat

• Protect the body from space radiation

The Space Suit should:

• Be airtight and resistant to external influences

• It should allow as much unrestricted movement as possible

• It should have a large tensile strength because of the gas pressure inside the garment

The Space Suit also should:

• Allow for communication in airless space

• The radio communication gear allows the astronauts to keep in touch with each other and with the astronauts inside the space station

• It also has a very sensitive alarm system in case a call for help is needed

The Space Suit also should:

Communications Carrier Assemblywith built-in earphones and a

microphone

The evolution of the space suit from large and

bulky to streamlined (1969 to 2020?)

• The Mercury space suit was un-pressurized and served only as a backup for a possible spacecraft cabin pressure loss (an event that never happened)

• It had laced boots, a helmet that attached by a collar ring, and gloves

• It was cooled by an external fan and received oxygen via tubes connected to the space craft

The Mercury space suit (1961-1963)

Evolution of the Spacesuit

• The Apollo suit had to be redesigned for extra vehicular activities (EVA’s)

• It had boots, gloves, a communications cap and a clear plastic helmet

• During lift-off the suit’s oxygen and cooling water were supplied by the ship

An Apollo space suit from 1975

Evolution of the Spacesuit

The Apollo pressure space

suit for EVA’s consisted of

many layers:• Three layers of nylon to hold

the pressure• Five layers of aluminized

Mylar interwoven with Dacron and two layers of Kapton for heat protection

• Two layers of Teflon coated cloth (nonflammable) for protection from scrapes

The Spacesuit worn by Neil Armstrongon Apollo 11 mission (1969)

Evolution of the Spacesuit

• During the early flights of the space shuttle astronauts wore a brown flight suit to protect them if the cabin pressure failed

• As space shuttle flights became more routine astronauts stopped wearing pressurized space suits during lift off and began wearing light blue cover-alls, black boots, and a communications helmet

Space suits on early shuttle missions

Crew of Challenger just prior to launch

Evolution of the Spacesuit

• After the Challenger disaster in 1986 NASA required all astronauts to wear pressurized space suits during lift-off and re-entry

• These orange pressurized suits had a communications cap, helmet, boots, gloves, parachute and inflatable life preserver

• These space suits were designed only for emergency use

Latest space suit used on the Space Shuttle

Evolution of the Spacesuit

• The Extravehicular Mobility Unit (EMU) is used for space walking from the shuttle and the space station

• The EMU has 13 layers of material including an inner cooling garment, pressure garment, thermal micrometeoroid garment, and an outer cover

• The materials used are nylon tricot, Spandex, urethane-coated nylon, Dacron, neoprene-coated nylon, Mylar, Gortex, Kevlar, and Nomex

The Extravehicular Mobility Unit

Evolution of the Spacesuit

The EMU consists of:• Gloves, helmet, torso assembly• Liquid Cooling and Ventilation

garment (to remove excess body heat)

• Communications Carrier Assembly (microphones and earphones)

• Extravehicular Visor assembly (to protect from sunlight)

• In-suit drink bag• Urine collection bag• Primary Life Support Subsystem

(provides oxygen, removal of carbon dioxide, power, cooling water, radio equipment, and warning system)

Evolution of the Spacesuit

Evolution of the Spacesuit

The spacesuit, including life support system, weighs about 310 pounds. If an astronaut weighing 175 poundswears the complete suit, the total weight would be 495 pounds!

• To help the astronauts move around freely while performing a spacewalk, a manned maneuvering unit (MMU) was attached to the EMU

• The MMU was a nitrogen propelled backpack that allows the astronaut to fly with precision

• The MMU was used 9 times on 3 Space Shuttle missions in 1984

Evolution of the Spacesuit

Astronaut Bruce McCandless madethe first untethered spacewalk in February 1984 (photo by NASA)

• Over 150 spacewalks (EVA’s) have been needed for construction of the International Space Station

• Tethers, safety grips and the robot arm are used for spacewalks now, but what happens if a problem occurs and the astronaut begins to float away into the void of space?

Evolution of the Spacesuit

Spacewalk using the robotic arm (NASA)

• NASA has a device called Simplified Aid For EVA Rescue (SAFER)

• It is a self-contained maneuvering unit worn by astronauts that relies on small nitrogen-jet thrusters with limited amount of propellant to let them move around in space

• It is to be used in emergencies only and so far has never been needed

Evolution of the Spacesuit

SAFER is worn like a backpack

• Apollo moonwalkers worked in space suits that limited a person’s flexibility to perform tasks

• These spacesuits cocooned an astronaut in a bubble of pressurized air and weighed more than 100 pounds

Jack Schmitt from Apollo 17 missionIs shown on the Moon in 1972

Future Spacesuits

• A trip to Mars will require more thought than a trip to the space station

• Unlike Earth, Mars does not have a magnetosphere to protect astronauts from radiation and micrometeors

• You would also be exposed to sand storms and a hyper-cold environment

• The space suit would also need to be light enough to move around and explore in Martian gravity

Future Spacesuits

• Future space explorers on the Moon and Mars could be outfitted in lightweight, high-tech spacesuits that offer far more flexibility than the bulky suits that have been used since the 1960’s

Artwork by Cam Brensiger

Future Spacesuits

• Research is underway at MIT on a Bio-Suit system designed for travel to Mars

• It looks like a spandex leotard made out of a stretchy, skin-like polymer that encases the body in a flexible shrink-wrap that prevents the wearer from exploding in the vacuum of space

Artist’s image of the Bio-Suit

Future Spacesuits

• The Bio-Suit is not only much lighter than conventional spacesuits but it can be outfitted with chemical sensors, wearable computers, and thermal threads for controlling body temperature

Artwork by Cam Brensiger

Future Spacesuits

• NASA is developing “hard suits” that are more flexible, more durable, lighter weight, and easier to put on than current space suits

Future Spacesuits

The AX-5 Hard Suitbeing developed by NASA

• Space suits on the shuttle are designed to work in a vacuum. The shuttle suits would weigh about 19 kg (42 lbs) on the Moon and 43 kg (95 lbs) on Mars

• Lighter EMU suits will be needed to prevent the astronauts from becoming exhausted during long periods of surface exploration

Future Spacesuits

The Mark III Hard Suitbeing developed by NASA

What would a future spacesuitlook like?