Space Life
Sciences
Fundamentals of Space Medicine — Chapter 1
Introduction to
Space Life Sciences
Gilles Clément, Ph.D
CNRS
"Cerveau et Cognition" Laboratory
Toulouse, France
Kluwer Academic Publishers • Copyright © 2003 • All rights reserved
1
Space Life
Sciences
Key Concepts
• Space Life Sciences: What is it ?
Where we are
• The historical context of human spaceflight
How we got there
• The importance of continuing research
before long-duration exploration missions
can be safely undertaken
Where do we go from here
2
Space Life
Sciences
Space Life Sciences—What is it
• Life Sciences are specifically devoted to the working of the
living world (from bacteria and plants to humans)
• On Earth, all living organisms have developed as a result of
constant exposure to 1-g gravity
• Space Life Sciences open a door to understanding
ourselves, our evolution, the working of our world without the
constraining barrier of gravity
• Beside microgravity, during space flight living organisms are
also affected by ionizing radiation, isolation, confinement,
changes in circadian rhythms (24-hr day/night cycle), etc.
• Objectives of space life sciences:
– Enhance fundamental knowledge in cell biology and
human physiology
– Protect the health of astronauts
– Develop advanced technology and applications for space
and ground-based research
3
Justification for Human Spaceflight
• Robotics versus Human crews
= Apples versus Oranges
– Human Pros: intelligent operators,
efficient end-effectors
– Human Cons: expensive,
complexity of habitable environment
Photo NASA
Space Life
Sciences
• Human spaceflight critics often discount the value of
Life Sciences on the “Discovery Ledger (Big Book)” —
often due to following fundamentals differences:
– Physical Sciences: more concrete discoveries in
relatively unexplored sphere
– Life Sciences: an inherently inexact science;
context of background physiological variability;
requirement for repeated measurements
4
Space Life
Sciences
Space Medicine versus
Space Physiology
• Space Medicine
– To solve medical problems encountered in spaceflight
– Includes some adaptive changes (e.g., space motion
sickness), environmental exposures, etc.
– Includes also some non-pathologic changes which
become maladaptive on return to Earth (e.g., bone loss)
– Outlook is operational, views problems/peculiarities
from standpoint of mission impact
• Space Physiology
– To characterize response to space, especially 0-G
– Necessary knowledge base for above
– Outlook is investigational, views problems/peculiarities
from standpoint of scientific return
5
Space Life
Sciences
Where we are (as of 1st July ‘03)
• Total number of persons who have flown in space: 433 (41 )
• Cumulative spaceflight time: 72 years (26.410 days)
• Mean spaceflight duration: 28 days
• Cumulative spaceflight duration by individual:
– Polyakov (679 days; 2 flights) 22 months
– Avdeyev (748 days; 3 flights) 25 months
• Re-adaptation to Earth gravity stated
" to be 90% complete [after 6 years] "
—Valery Polyakov (during
a science conference)
Photo CNES
• How did we get there?
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Space Life
Sciences
Major Space Life Sciences Events
7
• 1783: Two French gentlemen ride a hot-air (Montgolfier) balloon
• 1951: First successful (non-orbital) flight of a sounding
Photo NASA
after a few days)—followed by monkeys
Photo NASA
• 1957: Dog Laika first living creature into orbit (died
Photo CNES
rocket with a monkey and 11 mice (previous
attempts since 1948 were not successful)
Space Life
Sciences
Major Space Life Sciences Events
Photo NASA
• 1959: Selection of 7 American astronauts
Photo RSA
• 1960: Selection of 11 Soviet cosmonauts
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Space Life
Sciences
Major Space Life Sciences Events
9
• 1961: First human to orbit the Earth
(Y. Gagarin)
• 1963: First woman (V. Tereshkova)
Photo CNES
Photo NASA
in space—second Russian
woman (S. Savitskaya) did
not fly until 1982
• 1965: First space walk (Extra-Vehicular Activity)
Space Life
Sciences
Major Space Life Sciences Events
• 1965-66: Longest stay in space is 14 days (Gemini 7)
— first observations on human body adaptation
— artificial gravity first tested (Gemini 11)
Photos NASA
•
•
•
•
70’s : Salyut, Skylab — start of detailed SLS investigations
1981: First space vehicle piloted during return (Shuttle)
1994: Longest stay in space is 14 months (MIR)
2000: First expedition crew on board ISS
10
Space Life
Sciences
Human Spaceflight Experience
Adapted from Reschke and Sawin (2003)
11
Space Life
Sciences
Human Spaceflight Experience
greater than 30 days
12
Space Life
Sciences
Humans in Space
• First space missions were to demonstrate that humans
could survive a journey into space
• Some people doubted whether humans could endure
the g forces of launch and re-entry, or swallow, or sleep
in the absence of gravity
• Some predicted that "the bowels would not work without
gravity, the heart might cavitate like a pump, or become
so weakened as to prohibit return to Earth"
• How long can humans live in space, and how effectively
can they work in space are still open questions
• Living and working is far different from merely surviving
Movie:
• After extended stays in13_impossi
space, can people return safely
to Earth and lead normal, healthy lives? Such questions
are much more difficult than questions of survival
because they require sophisticated scientific
experimentation
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Space Life
Sciences
Surviving the Odyssey
14
Space Life
Sciences
What Really Occurs
• No up or down — disorientation, nausea
• Fluids shift towards head — « puffy » face, sinus
congestion, headache, changes in smell and taste
• Antigravity postural (extensor) muscles not used —
Photos NASA
new locomotion pattern, « chicken » legs, muscle
strength and endurance decrease
15
Space Life
Sciences
What Really Occurs
• No up or down — disorientation, nausea
• Fluids shift towards head — « puffy » face, sinus
congestion, headache, changes in smell and taste
• Antigravity postural (extensor) muscles not used —
new locomotion pattern, « chicken » legs, muscle
strength and endurance decrease
• Fluids volume decreases
changes in heart volume,
heart rate, and blood
pressure, breathing
difficult (less red blood
cells)
• Bone density
decreases by 1-3%
per month
16
Space Life
Sciences
What Really Occurs
• No up or down — disorientation, nausea
• Fluids shift towards head — « puffy » face, sinus
congestion, headache, changes in smell and taste
• Antigravity postural (extensor) muscles not used —
new locomotion pattern, « chicken » legs, muscle
strength and endurance decrease
• Fluids volume decreases — changes in heart rate and
Photo NASA
blood pressure, breathing difficult (less red blood cells)
• Bone loss
• Intervertebrate disks less compressed —
height increases, back pain
• Sleep disorders
Adapted from Lujan and White (1994)
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Space Life
Sciences
What Really Occurs
• No up or down — disorientation, nausea
• Fluids shift towards head — « puffy » face, sinus
congestion, headache, changes in smell and taste
• Antigravity postural (extensor) muscles not used —
new locomotion pattern, « chicken » legs, muscle
strength and endurance decrease
• Fluids volume decreases — changes in heart rate and
• Bone loss
• Intervertebrate disks less compressed —
height increases, back pain
Photo NASA
Photo NASA
blood pressure, breathing difficult (less red blood cells)
• Sleep disorders
• Sharper vision, but light flashes (radiation)
• Psychological troubles
18
Space Life
Sciences
Issues for Human Missions
• Preflight:
– Astronaut selection, crew selection, medical training
• Inflight:
– Acceleration, vibration, noise
during launch and landing
Soyuz
Movie:
19_launch
Shuttle
19
Space Life
Sciences
Issues for Human Missions
• Preflight:
– Astronaut selection; crew selection; medical training
• Inflight:
– Acceleration; vibration; noise during launch and landing
– Physiological adaptation: heart (dys-rhythmias) and blood
vessels, muscles (strength), bones (fractures, renal stones),
nervous system, immune system (infection)
– Psycho-sociological issues (support)
– Environmental issues: toxic substances, pressure changes
– Extra-Vehicular activity (EVA): strain on muscles and bones,
decompression-related disorders
– Radiation (sterility, cancer)
– Crew medical officer: diagnosis, treatment (surgery)
– Emergency return
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Space Life
Sciences
Issues for Human Missions
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– Piloting
– "1-g feels like 4-g"
– Emergency egress
– Standing: orthostatic intolerance
– Walking: postural instability
– Motion sickness
(Mal de Débarquement)
– Muscle and bone weakness
– Decreased exercise capacity
– Return to flight status
Photo NASA
• Postflight:
Space Life
Sciences
Countermeasures
• 2 daily 1-hour sessions of exercise:
Photos NASA
– Treadmill with axial loading
– Cycle ergometer
– Resistive exercise
– Traction on “bungee cords”
• Low Body Negative Pressure
• Fluid loading before re-entry
22
Space Life
Sciences
Human Mars Mission
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Space Life
Sciences
•
•
•
•
•
Challenges for a Mars Mission
Crew selection
Onboard medical officer
Radiation dose
Bone loss
Advanced Life Support Systems
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Spaceflight Life Support
• Human requirements
25
Photo NASA
Space Life
Sciences
– Hygiene, sanitation
– Nutrition (adequate, appealing)
– Rest (avoid chronic fatigue)
– Exercise (fitness, recreation,
motivation)
– Human performance (psychosocial, workload, circadian factors)
– Atmosphere, temperature, lighting, noise
– Food, waste
– From physico-chemical (recycled) to
bioregenerative (ecologically closed)
• Biosphere 2
• Mir Greenhouse
• Bio-Plex
Photo ESA
• Life support systems
Space Life
Sciences
Greenhouse in Space
26
• Critical questions to be
addressed :
– How far can we reduce
reliance on expendables?
– How well do biological and
physico-chemical life
support technologies work
together over long periods
of time?
– How do various
contaminants accumulate
and what are the long-term
cleanliness issues?
Photo NASA
– Is a “steady state” condition
ever achieved with
biological systems?
Space Life
Sciences
Challenges
27
• Short-duration spaceflights presumably OK for tourists
• For long-duration missions, the MIR experience indicates
that current inflight countermeasures are not optimal
Photo CNES
Movie:
27_cosmonaut
• Using the current countermeasures methods, humans
would not be operational after landing on Mars
• Artificial gravity probably the most efficient countermeasure
Space Life
Sciences
Artificial Gravity
• Principle of centrifugation
• Criteria for comfort (less motion sickness with lower
angular velocity; low velocity means large radius)
for a
effective
• For interplanetary travel the design isRecommended
most likelyzone
to be
human performance in rotating
short-arm centrifuge... combined with muscular
spaceexercise
systems
Movie:
28_hyperg
Movie:
28_centrifuge
Photo NASA
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Space Life
Sciences
Future Research
29
• Space Life Sciences research is on hold now
• ISS should be ideal for study of fundamental biological
processes—new science: gravitational physiology; no
Nobel prize yet, but given prizes have been challenged
amphibians, mammals after several
generations without perceived gravity
Document NASDA
• Think about development of insects,
Movie:
29_frog
• Changes seen at cellular level.
However,
too much publicity on biochemical factories in space
• Plants in space. Life support systems: how to move from
physico-chemical to closed ecological life support systems
Photo NASA
• Human Mars mission. Probably the longest period away
from Earth to date; also probably the longest exposure to
hypogravity (1/3 g) environment to date
Space Life
Sciences
• Biology
Benefits of SLS Research
– Improve overall health of people of all ages
– Improve crop yields using less nutrients and smaller surface
– Advance understanding of cell behavior
• Biotechnology
– Provide information to design a new class of drugs to target
specific proteins and cure specific diseases
– Culture tissue for use in cancer research/surgery and bone
and cartilage injuries
• Biomedical Research
– Enhance medical understanding of the role of force on bone in
disease processes including osteoporosis (bone loss)
– Advance fundamental understanding of the brain and nervous
system and help develop new methods to prevent and treat
various neurological disorders (e.g., multiple sclerosis)
– Develop methods to keep humans healthy in low-gravity
environments for extended time periods
• Education
– Use science on orbit to encourage and strengthen science
education on Earth
30
Space Life
Sciences
Additional Reading
31
• Clément G (2003) Fundamentals of Space Medicine. Dordrecht:
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Kluwer Academic Publishers
Mullane MR (1997) Do Your Ears Pop in Space? New York, NY: John
Wiley & Sons
Oser H, Battrick B (1989) Life Sciences Research in Space. ESA SP1105. Paris, France: ESA Publication Division
Wassersug RJ (2001) Vertebrate Biology in Microgravity. American
Scientist 89: 46-53
Wolfe T (1979) The Right Stuff. New York, NY: Farra, Straus & Giroux
A Strategy for Research in Space Biology and Medicine in the New
Century. National Research Council. Washington, DC: National
Academy Press,1998
National Geographic. The Body in Space. January 2001 issue
Fifth Symposium on the Role of the Vestibular Organs in Space
Exploration. NASA SP-314, 1973
http://www.nsbri.org/HumanPhysSpace/index.html
http://weboflife.arc.nasa.gov/
http://lifesci.arc.nasa.gov/