Transcript Methods of Astrobiology By Michael Timmons

Methods of
Astrobiology
By
Michael Timmons
Analytical/Radio/Nuclear (ARN)
Seminar Spring 2006
Overview
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What is COSPAR
Requirements for Life Detection
Soil Experiments in the Atacama Desert
TWEEL and Robotic Soil Analyzer
Conclusions
COSPAR
• COMMITTEE ON SPACE RESEARCH
• Established in 1958 by the International
Council for Science
• Objectives are the progress of all kinds of
research carried out with the use of space
means
• Strives to promote the use of space
science for the benefit of mankind
COSPAR Requirements for Life
Detection Experiments
• Guidelines to avoid the harmful contamination
and also adverse changes in the environment of
the Earth resulting from the introduction of
extraterrestrial matter
• Planetary protection policy, both as an
international standard on procedures to avoid
organic-constituent and biological contamination
in space exploration
• Five Categories of requirements
Category I
• Includes any mission to a target body
which is not of direct interest for
understanding the process of chemical
evolution or the origin of life.
• No protection of such bodies is warranted
and no planetary protection requirements
are imposed by this policy
Category II
• Missions to those target bodies where
there is interest relative to the process of
chemical evolution and the origin of life
• Only a remote chance that contamination
carried by a spacecraft could jeopardize
future exploration
Category III
• Missions (mostly flyby and orbiter) to a
target body of chemical evolution and/or
origin of life
• Significant chance of contamination which
could jeopardize a future biological
experiment
Category IV
• Missions (mostly probe and lander) to a
target body of chemical evolution and/or
origin of life
• Significant chance of contamination which
could jeopardize future biological
experiments
Category V
• Comprise all Earth-return missions
• Concern is the protection of the terrestrial
system, the Earth and the Moon
• Requirements that encompass those of
Category IV plus a continual monitoring of
project activities, sterilization procedures
and containment techniques
Atacama Desert
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Located in Northern Chile
Known as the driest place on Earth
A series of dry salt basins
Rain has never been recorded in some
localities
• Virtually sterile environment
• Location used by NASA to test instruments
for future Mars missions
Microbial Life in Atacama
• Recently discovered low numbers of
bacteria and recoverable bacterial DNA
• Results demonstrate the existence of life
in one of the driest regions on Earth
• Mars, like the Atacama Desert, might be
conducive to microbial life
• Findings suggest techniques that might be
used during future Mars missions
1976 Viking Missions to Mars
• Provided strong evidence for microbial life
• Shortcomings of the missions:
The huge expense of sterilizing the
entire spacecraft to protect the integrity of
life detection experiments
The lack of a practical robotic life
detection package
Evidence for Life on Mars
• Ice lies tens of centimeters beneath the
surface of wide areas of Mars
• Meteorites have provided evidence of past
life forms
• Discovery of extremophiles, such as in
Atacama, demonstrates that many
terrestrial microbial forms can withstand
environmental extremes
Ideal Instrumentation Design
• Complies with COSPAR requirements for
life detection experiments
• Minimal sterilization area
• Allow interchangeable devices for
conducting multiple experiments
• Robust delivery system
TWEEL
• Twin Wireless Extraterrestrial Experiment
for Life
• An ejectable probe sheathed within its own
cylindrical case fixed within the canister
• Each individual TWEEL contains the
equipment for a variety of experiments (i.e.
pH, temperature, water sensors)
Antenna
FM Radio
TWEEL EQUIPPED FOR LR/CIRCADIAN
RHYTHM/PHOTOSYNTHESIS
EXPERIMENT
 Detector
Baffle
Extended Position
Springretained
air vent
White
LED
Light pipe/
diffuser
Test Chamber
Evolved
gas counting
space
Battery
Programmer
Decelerationactivated
penetration
controller
Battery
Scoop
Ampoule
TWEEL Operation
• TWEELs are aerodynamically designed so
that their noses impact first
• The depth of penetration is controlled by
flanges that deploy upon impact
• TWEEL launches may be simultaneous or
individual
• Each TWEEL has internal two-way radio
communication with the lander
Robotic Mars Soil Analyzer
Pop
Cover
TWEELs
Sterile
Canister
Launch
Charge
Wind Vane
3-D Gimbaled
Rotating Platform
Platform
Detente
Conclusion
• The Robotic Soil Analyzer provides a
simple, low-cost, and convenient method
for testing Martian soil
• Adheres to COSPAR requirements for life
detection experiments
• Provides multi-experiment conditions
• The samples excavated by the TWEELs
are pristine
References
A sterile robotic Mars soil analyzer, Gilbert V. Levin, Joseph D. Miller, Patricia Ann Straat, and Richard E. Hoover, Spherix Incorporated,
University of Southern California, NASA Marshall Space Flight Center, http://mars.spherix.com/SPIE_2002_FINAL.htm
Rafael Navarro-González, Fred A. Rainey, Christopher P. McKay, Science, vol. 306 (2004)
R. M. Maier, K. P. Drees, J.W. Neilson, D. A. Henderson, J. Quade, J. L. Betancourt, Reports, p. 1018 (2003)
G. M. Colores, R. E. Macur, D. M.Ward,W. P. Inskeep, Appl. Environ.Microbiol. 66, 2959 (2000)
5. M. J. Ferris, G. Muyzer, D. M. Ward, Appl. Environ. Microbiol. 62, 340 (1996)
R. Navarro-González et al., Int. J.Astrobiol., suppl. 1, p. 82 (2004)
http://www.cosparhq.org/
http://www.cosparhq.org/scistr/PPPolicy.htm
http://sunsite.dcc.uchile.cl/chile/turismo/atacama.html
http://en.wikipedia.org/wiki/Atacama
http://www.space.com/news/spacehistory/viking_life_010728-1.html
http://www.windows.ucar.edu/tour/link=/mars/exploring/viking_overview.html&edu=high