Lecture 1: The Problems with Spaceflight

Question 1

Our body’s physiology and anatomy are STILL THE SAME/DIFFERENT as our plane-dwelling ancestors and yet we are exposing them to novel and extreme situations.

Answer 1

STILL THE SAME

Question 2

we have to place human physiology under ____ to achieve space exploration

Answer 2

GREAT STRESSES

Question 3

why do we even bother with space exploration??

Answer 3

• curiosity (exploration)
• resources (mind astroids etc)
• aliens
• our suns going to die, next life??

Question 4

what are the key events during a flight into orbit and beyond?

Answer 4

• take off (lift off)
• massive acceleration –> HIGH G phase (3-4g)
• -2 minutes = 3000mph
• -into orbit = 17,500 mph
• once in orbit = microgravity
• deorbit = high g on deorbit and reentry ~1.5g
• landing = 235mph

Question 5

lunar missions: flight path

Answer 5

• lift off (cape kennedy)
• orbit earth once (accelerate
• slung away from earth hyperbolic orbit
• moons gravity capture you,
• spacecraft orbits moon, part of spacecraft break off
• spacecraft then launch from moon, accelerate to leave moon gravity
• capture in earths gravity

Question 6

g loads in lunar missions

Answer 6

similar g loads on ascent but greater on re-entry but greater on re-entry because velocity is much greater (25,000mph compared to shuttles 17500mph)

Question 7

What exactly is orbit?

Answer 7

• golf ball on top of mountain (hit hard and harder)
• curve round the earth, because travelling at speed will never touch earth again
• 90 mins to go all way around
• Apogee and Perigee

Question 8

apogee

Answer 8

= place of take off in orbit, furthers point from earth

Question 9

perigee =

Answer 9

closes part to earth in orbit

Question 10

orbit can happen at which distance from earth?

Answer 10

ANY, if going fats enough.

-just obstacles get in the way

Question 11

ON /IN orbit

Answer 11

ON

Question 12

human body and high g

Answer 12

lying semi-recumbent, v high ^-forces can be tolerated for short times (35g for 0.03 sec) but 10g for 30secs plus
– position favourable as doesnt starve brain of blood

Question 13

G-LOC

Answer 13

gravity induced loss of consciousness

Question 14

mars cycler

Answer 14

• special kind of spacecraft trajectory that encounters Earth and Mars on a regular basis
• take much longer than a direct flight
• invented by Buzz Aldrin

Question 15

how does space effect the eyes:

Answer 15

eyes become primary motion sensors, more relied upon to determine orientation

Question 16

getting a person into space is a balance between

Answer 16

balance between engineers and physiological issue

Question 17

engineers vs physiological issues VELOCITY

Answer 17

engineers: adequate velocity required to get onto orbit and beyond
- physiological issue = too fast, leads to death

Question 18

engineers vs physiological issues ENVIRONMENT

Answer 18

E = earth-like environment (‘shirt sleeves) (including adequate nutrition) –> PI = must be maintained for whole time

Question 19

engineers vs physiological issues RADIATION

Answer 19

E = protection from radiation (Solar) 
PI = exposure to radiation can result in cancers and immediate death

Question 20

what does the body have to deal with when travelling in a spacecraft

Answer 20

• high G-force on take off
• microgravity (loss of bone density –> renal calculi, loss of muscle mass, vestibular system, visual system[scott kelly])
• radiation (solar mass ejections- ‘solar flares’ very damaging in deep space)

Question 21

What does the body have to deal with when outside the spacecraft?

Answer 21

• space suit = mini space craft
• atmospheric stability needed (breathable gas mixture and gas pressure)
• thermal stability (humans survive only in small range)
• micrometeroid impact (puncture suit)

Question 22

space temp =

Answer 22

shade = -200 celsius to sun = + 200 C