Bringing Life to Mars,
and Mars to Life
Terraforming defined
• Genesis of term
• Basic definition
– "...a process of planetary engineering, specifically directed at
enhancing the capacity of an extraterrestrial planetary environment
to support life. The ultimate in terraforming would be to create an
uncontained planetary biosphere emulating all the functions of the
biosphere of the Earth–one that would be fully habitable for human
beings.” - Martyn J. Fogg
• Ecopoesis – partial terraforming
• Biospheres and Terran ecosystem services
Exploration/colonization
• ISS vs. Terran biospheres
– Materials imports and exports
• Lunar and Martian outposts
– Closed loop systems
– In-situ resource utilization
– Economic & political pressures
Earth-like Mars
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Ecosystem size, complexity and stability
Interest in terraforming Mars
Day length
Year length and seasonality
Land surface
Surface gravity
Alien Mars
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Mars is cold (-63 oC vs. 15 oC) (heat budget)
The air is thin (6.4 mb)
and ‘unbreathable’ (95% CO2, N2, Ar, O2)
No liquid water
No global magnetic field
Earth and Mars history
Extant life???
Cold, dry planet
H2O loss
CO2
sequestration
Magnetosphere
loss
Techtonic
shutdown
Multicellular life
Atmospheric O2
Climatic cycles,
Plate techtonics
Core cooling
Early life????
Warm, wet, anaerobic?
Early life
Warm, wet, anaerobic
Mars today, re-examined
• Flotilla: Pathfinder, MGS, Odyssey, Mars
Express, MER Spirit & Opportunity
• Polar icecaps: water ice and CO2
• Subsurface water, Surface water(??)
• Implications for current water cycle
• Cycles of climate change
• Search for carbonates
Mars terraforming goals
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Raised surface temperature (~ 60oC)
Increased mass of the atmosphere
Availability of liquid water
Protection from UV and cosmic rays
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Composition of atmosphere
Runaway greenhouse effect
• CO2 and H2O reserves
• Polar CO2 dynamics
• Positive feedback
mechanism to raise T and
Pa
• Impacts on water cycle
• Unknowns: reserve levels
and formats, time
constants
Triggering the runaway
CF3CF2CF3, CF3SCF2CF3,
SF6, SF5CF3, SF4(CF3)2
• Artificial greenhouse gas
production
• Initial interest in CFC’s
• Search for designer
greenhouse gasses
• Unknowns: effectiveness,
lifespan, in-situ resource
utilization issues
Other triggers
• Change albedo of icecaps
• Orbital mirrors
• Cometary bombardment
• Nuclear explosions in regolith
Atmospheric composition
• Results of greenhouse runaway
• How to oxygenate the atmosphere?
– Carbon cycle – carbon sequestration needed
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Candidate primary producers for ecosystem
How to build functional ecosystems??
Time to build up O2: 1000’s of years
Nitrogen issues
Mars terraforming possibilities
• Planet can be warmed and the atmosphere
thickened
– Easier to work outside and harvest resources
• Replicating Terran biospheres is much more
difficult, and will not happen soon
Environmental ethics
Discussion time
Environmental ethics concepts
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Obligations and restrictions
Moral standing and moral agents
Intrinsic vs. instrumental values
Anthropocentrism
Biocentrism
Ecocentrism
End of show
Atmospheric heat budget
Polar icecaps
Subsurface water
Recent surface water?
Polar CO2 dynamics
• Relationships
between Pa, T
and Pv
• Stable and
unstable
equilibrium
points
Carbon Cycle
Deep ocean
burial of C
Extremophiles
Cyanobacteria
Cryptoendoliths
Ecosystems