Space Suits (Why do we wear them?)
Five Reasons Space Debris Pressure Oxygen Radiation Temperature
Project Mercury • As backup in case of loss of cabin pressure—never needed • 5 psi pure O2 • Outer layer of suit was slightly smaller than pressure layer • Joints were not articulated, but bent in a gentle curve –any movement caused an increase in total pressure • 1st (Alan Shepard) had no UCD • 3rd (John Glenn) 1st to wear flotation device
Project Gemini • To be used in cases of: • accidental loss of cabin pressure • EVA (“space walks”) • abort ejection • Umbilical tether provided O2 (pressure and breathing) and communications • The added physical activity caused the suits to overheat and the helmet visors to fog up.
Project Apollo • To be used in cases of: • accidental loss of cabin pressure • EVAs in the harsh lunar environment • First liquid cooling garment • Bellows joints • Custom boots & gloves • Independent life support • EVA suits got slimy with the previous days’ sweat
Project Skylab • Simplified Apollo suit • Astronaut life support assembly worn on chest (pressure-control unit & attachment for tether) • PLSS smaller, but similar to Apollo • Tether for O2 & com. like Gemini • Emergency oxygen package • Allows brief tether-free travel
EMU(Extravehicular Mobility Unit) • Adjustable • Rechargeable batteries for power • Shuttle: recharged on Earth after each mission • ISS: recharged from station power • Replaceable LiOH canisters • Ventilation prevents perspiration build-up • May 1993, frostbite to Story Musgrave’s fingers leads to electrically heated fingertips in gloves.
Launch & Landing • ACES (1994-) • Advanced • Crew • Escape • Suit • Survival backpack • Life raft • Parachute • UCD • Light sticks • SPORT • Prior to the loss of Challenger (above) Shuttle crews wore: • Basic blue flight suit • Helmet (oxygen) • Flotation vest during launch and re-entry.
Russian Orlan (Орлан) • Orlan means “Sea Eagle” • Less mobility than Shuttle EMU • Early versions: • No food/drink • No UCD • No PLSS (like Gemini) • 5 minutes to don/doff • 9 hour operating limit • Non-adjustable
Orion MPCV Suits • A launch & landing and ACES-type suit • Pressure suit • Capable of being modified/adapted • NASCAR-style HANS (Head And Neck Support) enhanced suit • Additional layers extend suit’s capabilities • Configuration 1=Launch, Landing, Aborts—uses a life support umbilical hose (like Gemini) • Configuration 2=In-flight EVA suit—uses a PLSS backpack with a rear-entry door (like Orlan) • Configuration 3=Extra-terrestrial sorties—Fire-retardant outer shell, additional hard points to resist damage, boots
Testing the Future • The Biosuit(in development at MIT) • Like a wetsuit, does not use pressure • Gas-filled gloves & helmet
Space Suit Design pace Debris—micrometeorites & trash @ ≥17,500 mph ressure—What’s inside must balance what’s outside. xygen—We need it. Space has none. We bring our own. adiation—Kill you. Cook you. Cancer. Non-fun mutation. emperature—Frozen or fried, being dead or hurt is still being dead or hurt. • S • P • O • R • T • Astronaut comfort • Range of motion • Time to don/doff • “Biological support”—Food, water, UCD, etc.
Advanced AcademySpace Suit Design You have an astronaut, usually represented by a fruit or vegetable. You must protect him (her, it) • against the hazards of space travel (S.P.O.R.T.) • with a suit that you design and build • in a matter of minutes • using your choice of the household materials provided.
Advanced AcademySpace Suit Design • You will begin with 100 points. • From these 100 points you will lose 10 points per layer of your “suit.”(You cannot go into “negative points,” so you may only have 1-10 layers.) • To the remaining points (0-90) you will add Survival points that you may earn based on your suit’s performance.
Advanced AcademySpace Suit Design • Your astronaut will be held underwater for 60 seconds.This will test for Pressure & Oxygen.If water can get in then the air can escape, and vice versa.The paper strip shows the result: • Wet=Failure Your astronaut has drowned. ( 0 points) • Damp=Fault Your astronaut got wet, but was saved. (30 points) • Dry=Success! Your astronaut is just fine. (60 points) • Your astronaut will be placed in a box with heat and UV bulbs for 5 minutes.This will test for Temperature & Radiation.Your thermometer strip will show the result: • >4°=Failure Your astronaut has roasted. ( 0 points) • 2-4°=Fault Your astronaut got too hot, but is okay. (30 points) • 0-2°=Success! Your astronaut is just fine. (60 points) • The paper strip shows the result: • white =Failure Your astronaut has been nuked. ( 0 points) • lt. blue=Fault Your astronaut has been irradiated. (30 points) • navy =Success! Your astronaut is just fine. (60 points) • You must undress your astronaut, read the thermometer, remove the paper strip, and re-dress exactly as before.This will test for astronaut comfort.(This is where you will read the thermometer and remove the paper strip.) • >2 minutes Like the EMU, your suit is cumbersome. ( 0 points) • 1-2 minutes Your suit is marginally easy to don/doff. (30 points) • <1 minute Like Orlan, your suit is easy to don/doff. (60 points) • Your astronaut will next be struck by a large nail dropped from a height of 5 feet or greater.This will simulate a Space Debris impact.We will undress the astronaut, get a final layer count, & look at the impact site: • >2 mm puncture Your astronaut has been impaled. ( 0 points) • <2 mm puncture Just a flesh wound. (30 points) • No visible damage Your astronaut is just fine. (60 points)