Deadline for symposia proposals has passed. Please contact
Marilyn L. Fogel, SOC Chair (m.fogel@gl.ciw.edu)
with questions regarding the symposia.
Astrobiology on the Moon
Conveners:
Lynn Rothschild
Director, Astrobiology Strategic Analysis & Support Office,
MS 239-20, NASA Ames Research Center, Moffett Field, CA 94035
Email: Lynn.J.Rothschild@nasa.gov
Norman Sleep
Professor of Geophysics
Stanford University
Stanford, CA 94305
Email: norm@pangea.Stanford.edu
Bernard H. Foing
Executive director , ILEWG
Chief scientist, ESA/SCI-S
European Space Agency ESTEC/SCI-S
Postbus 299 , 2200 AG Noordwijk
The Netherlands
+31 71 565 5647
Fax +31 71 565 4697
Email: Bernard.Foing@esa.int
Lunar exploration provides a high potential to foster the objectives of astrobiology.
Lunar geoscience studies help to understand the origin and evolution of Earth like planets.
The Moon played a key role in early Earth evolution. Lunar or cislunar telescopes on the Moon
can detect and characterize if life exists elsewhere in the universe. The Moon will be used for
emplacing life science experiments, human outposts, bases and biospheres that will play a key
role in the future of life beyond Earth. The symposium comes at a special time when US lunar
exploration architecture has been presented, and when international agencies are defining
their lunar and planetary exploration program. It will help to foster interdisciplinary
communication between astrobiologists, geoscientists, microbiologists and space scientists.
Topics include: The Moon as keystone to
study planetary evolution and astrobiology; Summary results and goals from ongoing lunar robotic
missions; Precursor missions and moon-based laboratory for astrobiology and life sciences; Human
bases, Living off the land and sustained; Searching on the Moon for samples from early Earth and life
There are many reasons why the time is right to highlight the moon as an astrobiological
topic. First, astrobiology focuses on the habitability of planets, and arguments have
been made, mostly in public rather than scientific fora, that a large moon such as ours has a
profound influence on habitability. If this is true, it has implications both for the
future habitability of the earth as our moon continues to recede, and for the search for habitable
planets elsewhere. Second, in light of President Bush’s Moon/Mars initiative,
lunar exploration has once again become a priority for NASA. This symposium is particularly
timely as it will be begin the discussion of how lunar science can aid the advancement of astrobiology,
for example, as the source of information for impact history on the early Earth. As plans
advance for lunar missions, the time is now to include astrobiology in the considerations.
Triggers of Mass-extinctions in the Earth’s history. Terrestrial vs. Extraterrestrial.
Applications for planetary habitability
Convener:
Alexander A. Pavlov, pavlov@lasp.colorado.edu
This symposium solicits papers that present new experimental data, modeling results
and observational constraints on the possible triggers of Mass-extinctions throughout
Earth’s history. Triggers of Mass-extinctions are very important in our understanding
of the evolution of life on Earth and will put useful constraints on the habitability of
Earth-like planets elsewhere. Emphasis will be placed on theoretical and observational
studies that provide constraints on the “necessary” magnitude of a specific
trigger, the probability for a specific trigger to occur and on the susceptibility of the
biosphere to such triggers during different periods of the Earth history.
Fundamental problems to be discussed include:
1) “Terrestrial” triggers – critical outgassing of the toxic gases
(H2S etc.), extreme warming events and CO2-poisoning, continental distribution, extreme
cooling events (including Snowball).
2) “Extraterrestrial” triggers – impacts, cosmic ionizing radiation,
variations in interstellar and interplanetary dust.
3) Biological constraints on triggers of mass-extinctions – tolerance of biota
(microorganisms and advanced life) to UV, temperature fluctuations, toxic gases, ionizing radiation.
4) Planetary habitability – e.g. which planetary systems are more susceptible to
impacts or irradiation hazard?
This is a truly interdisciplinary symposium which will bring together planetary scientists,
biologists, astronomers and geologists and would generate a lot of interest for general public.
Interdisciplinary Research in Cold Mars-Analogue Environments
Conveners:
Jennifer Eigenbrode & Marc Fries
Geophysical Laboratory
Carnegie Institution of Washington
5251 Broad Branch Rd., N.W.
Washington, D.C. 20015
Tel: +1 202 478 8987
j.eigenbrode@gl.ciw.edu
m.fries@gl.ciw.edu
Libby Hausrath
Department of Geosciences
Penn State University
302 Hosler Building
University Park, PA 16802
Tel: +1 814 865 9384
emh191@psu.edu
Mars analog sites feature a
combination of geological and environmental conditions that make them reasonable terrestrial
analogues for direct Martian studies. As such, studies at these sites are important
both for interpreting existing Mars data and for developing field instrumentation, protocols
and interpretive strategies for future Martian exploration. This symposium will address
methods and results from interdisciplinary cold-climate Mars analogue studies. Participants
are invited to contribute in
topics such as characterization of organic, biological, geochemical, and mineralogical
materials to decipher potential biosignatures, discussing microbial adaptations to cold-climate
habitats on Earth (and by extension on Mars), exploring the effects of weathering, biological
overprinting and contamination of geobiological records, testing for life in Mars-analogue
environments, addressing the challenges of in situ cold-climate life-detection
investigations, and presenting creative avenues in engaging the public in Mars-analogue studies.
How do “extremophiles” impact our perception of the habitability of Earth and
extraterrestrial environments?
Convenors:
Matthew O. Schrenk
Carnegie Institution of Washington- Geophysical Lab
5251 Broad Branch Rd. NW
Washington, DC 20015
m.schrenk@gl.ciw.edu
Julie A. Huber
Marine Biological Laboratory
7 MBL Street
Woods Hole, MA 02543
jhuber@mbl.edu
In recent years, studies of life at extreme environments have pushed our understanding of the habitable
range of conditions on Earth. Some of the notable findings include prolific microbial communities
in acidic mine drainage, intact organisms in both extremely low and extremely high temperature natural
systems, and microbial life in deep subsurface environments where both nutrients and energy sources may
be in short supply. Likewise, laboratory studies have pushed the boundaries of microbial activity
and survival, with new insights on temperature and pressure limits and cell metabolism as prime examples.
The proposed session will highlight work that places studies of the limits to life into a global
and/or planetary context. Cross-disciplinary communication in studies at the limits to life will
benefit the Astrobiology community by 1.) Improving the environmental relevance of biological studies,
and 2.) Integrating the most current understanding of microbial physiology and activity into the search
for extraterrestrial life.
Some of the interdisciplinary topics that we would like to highlight include:
- Integrated discussion of the physical, chemical, and temporal parameters that serve to define
microbial ecosystems
- Assessment of potential habitats for past or current extraterrestrial life: Are extreme
environments useful analogues?
- The use of “extremophilic” ecosystems to test life-detection criteria and
instrumentation
- Improved understanding of the role of “extreme environments” in the
evolution and proliferation of life on Earth
- Evaluating the contributions of extreme ecosystems to global biogeochemical cycles
Modern extreme environments:
-Deep subsurface work
-Mid-ocean ridges and ridge flanks
-Ultramafic-hosted sites
-Terrestrial hot springs
-Artic sea ice/ permafrost environments
-Acidic mine drainage/Rio Tinto
-Dry desert environments
Extraterrestrial and early Earth environments (present-day analogues and planetary settings)
-Mars, Titan, Europa, Venus,Other extraterrestrial systems? Early Earth
Astrobiological Achievements of the NASA Astrobiology Institute
Conveners:
Executive Council of the NASA Astrobiology Institute via Bruce Runnegar
NASA Astrobiology Institute
Ames Research Center
Moffett Field, CA 94035
Bruce.Runnegar@nasa.gov
Proposal: The NASA Astrobiology Institute (NAI) was founded in 1998
as a new way to do science (a distributed institute) and the help found the new field of
astrobiology. Seven years later, the Institute has 16-member team distributed across the
nation from Hawaii to Massachusetts. The proposed one-day session will highlight astrobiological
achievements of the NAI, as a microcosm of the progress of astrobiology as a whole.
Session plan: A half-day parallel session with a set of invited speakers
selected by the PIs (Executive Council members) of the 16 NAI teams. Not all NAI teams will be
represented in the program. This will be a carefully selected set of highlights
Sulfur on Earth and Mars: Microbiology, Mineralogy, Isotope Geochemistry, Photochemistry,
Role in Mars Exploration, Environmental Impact.
Conveners:
Lee Kump
Dept. of Geosciences, Pennsylvania State
University, 535 Deike Bldg.
University Park, PA 16802
lkump@psu.edu
Bruce Runnegar
NASA Astrobiology Institute
Ames Research Center
Moffett Field, CA 94035
Bruce.Runnegar@nasa.gov
Sulfur is a key element for environmental reconstruction and a powerful source of novel
biosignatures. The proposed session would deal with the following issues:
Atmospheric oxidation. On
Earth, the atmospheric roles of sulfur and oxygen appear to have reversed at the time of
the Great Oxidation Event (GOE) when the atmospheric biosphere first emerge. Prior to the
GOE, volcanic sulfur passing through the atmosphere was partitioned by photochemical
reactions into two reservoirs, each exhibiting anomalous “mass-independent”
isotope effects as measured by the ratios of 33S/32S versus 34S/32S. These changes are
recorded in sulfur minerals and are being used by some to understand the nature and
timing of the Great Oxidation Event, but others have different interpretations so this
session will also provide an opportunity to explore the controversy.
Novel chemistry. Experimental O and S gas-phase chemistry of the
mass-independent fractionation processes along with theoretical work is a hot field.
A chemical understanding of these processes will be of great importance to interpretations
of environmental conditions on the early Earth and Mars.
Novel microbiology. Deeper understanding of the many ways microorganisms
have and are using S compounds as a redox source of energy is being informed by studies
of microbial reactions; by isotopic effects associated with these reactions; by
whole-genome analyses of the organisms and their S metabolizing pathways; and by
biomarker studies which enable these pathways to be identified in sedimentary environments.
Novel histories. The recently realized ability to extract trace
sulfate from most sedimentary carbonates provides temporal access to the marine S
cycle throughout Earth history. It is now possible to measure the isotopic composition of both
the reduced and the oxidized reservoirs in all sorts of astrobiologically significant sites.
Sulfur on Mars. Mars may be the red planet because of the iron in the regolith,
but it is also S-rich (relative to Earth) from core to surface. The abundance of S, and sulfate
minerals, in surficial deposits has been recently. Understanding the origin and significance of
S, as well as the potential role of sulfates as environmental indicators and repositories of
potential biosignatures, will greatly inform future missions to Mars.
Sulfidic oceans and mass extinctions. Sulfur seems to have exchanged places
with oxygen or Fe as a dissolved components of deep ocean waters throughout Earth history.
Basically, Fe and S are incompatible components because iron sulfide is insoluble and oxygen
and sulfide are incompatible because of source/sink effects. Thus, the alternation in time of
these three components provides a way of explaining many poorly understood features of the
geological and paleobiological records, including local and planetary-scale mass extinctions.
Extraterrestrial pre-biotic chemistry: Synthesis in the Solar System and beyond
Convener:
Conel Alexander
DTM, Carnegie Institution of Washington
5241 Broad Branch Road
Washington DC 20015
e-mail: alexande@dtm.ciw.edu
Tel: (202) 478 8478
Fax: (202) 478 8821
Reginald Hudson
Eckerd College/NASA Goddard Space Flight Center
Yvonne Pendleton
NASA AMes Research Center
It has been suggested that organic matter in primitive meteorites and interplanetary dust particles (IDPs)
are largely interstellar in origin, and that they could have played a role in the origin of life on Earth.
If organic matter from meteorites/IDPs did influence the development of life and it formed in the interstellar
medium (ISM), the ubiquity of this material in the Galaxy has obvious consequences for the origin of life
outside the Solar System. The purpose of this symposium would be to bring together meteoriticists,
astronomers, and experimental and theoretical astrochemists to compare and contrast the organic matter
in various extraterrestrial objects (meteorites, IDPs, comets) and environments (protoplanetary disks,
ISM) with experiments and models, and explore what role, if any, exogenous organic matter could play in
the origin of life.
Exploring Planets Around Other Stars
Conveners:
L. Jeremy Richardson, NASA Goddard
richardsonlj@milkyway.gsfc.nasa.gov
Margaret C. Turnbull, Carnegie
turnbull@dtm.ciw.edu
Hannah Jang-Condell, Carnegie
hannah@dtm.ciw.edu
What are the prospects over the next two decades
for detecting habitable worlds and planetary systems like the one we inhabit? How are current space
missions contributing to this goal?
Since the first detection of a hot Jupiter around
a solar-like star 10 years ago, much progress has been made in the field of extrasolar planet detection
and characterization. Over 160 planets are now known to orbit other stars, and nine of these pass
in front of their parent stars as seen from Earth, which allows us for the first time to learn about
extrasolar planet sizes and atmospheric compositions. This symposium will provide an overview of the
current state of knowledge of extrasolar planets and a discussion of future prospects for detecting
Earth-like planets around nearby stars.
We anticipate talks summarizing the various
detection methods that have been successful so far, as well as techniques that are now being refined
for the next generation of planet-finding missions. We will discuss what we know and hope to
learn soon about planetary statistics (how common are Solar Systems like ours?), atmospheric
characterization of giant planets and terrestrial planets (including signs of habitability to life
as we know it), origins of planetary systems and implications for habiitability, signatures that
planets are currently forming within circumstellar disks, and the future proposed missions
for planet detection and characterization. All talks and discussion will stress the direct
connection between extrasolar planets and astrobiology.
Engaging Public Perceptions of Evolution: Challenges and Opportunities for Scientists and Science
Educators
Conveners:
Connie Bertka
Director, Program of Dialogue on Science Ethics and Religion
AAAS
cbertka@aaas.org
202-326-6618
Julie Edmonds
Co-Director, Carnegie Academy for Science Education
Carnegie Institution of Washington
jedmonds@pst.ciw.edu
202-939-1140
Life on Earth has existed in its present form since the beginning of time? According to a recent
2005 Pew Forum on Religion and Public Life Survey, forty-two percent of the American public thinks
the answer is “yes.” Even more sobering is the fact that this percentage has remained
nearly unchanged for decades. The most recent challenge to public understanding of science
in general, and evolution in particular, is “intelligent design.” ID has the potential
to appeal to an even broader public audience, as evidenced by the success of the Kansas State Board of
Education in changing the definition of science such that explanations beyond nature may be discussed in
the science classroom. If the scientific community at large wasn’t paying attention before,
we are now.
Science educators working with high school students, college students, and the public at large,
have had to confront this issue. This symposium will bring together a panel of educators, both formal
and informal, who have dealt specifically with the teaching evolution controversy to provide an opportunity
to both brief the astrobiology community on the present status of significant events, and to encourage a
broader discussion of challenges and opportunities.
Follow the Energy
Conveners:
Tori Hoehler
Research Scientist, Exobiology Branch
NASA Ames Research Center
(650) 604-1355
tori.m.hoehler@nasa.gov
Jan Amend
Associate Professor of Earth & Planetary Sciences
Washington University in St. Louis
(314) 935-8651
amend@levee.wustl.edu
Life universally requires energy to build and maintain organization and complexity in a universe that
is constantly moving towards maximum entropy. This need for energy represents a constraint on
habitability, origins of life chemistry, and the activities of extant organisms, including possible
biosignature formation. Thermodynamics, which describe the cycling of energy in chemical systems,
offers the potential to express these constraints in quantitative terms.
We propose a session that broadly considers the relationship between environment, energy, and life.
While biology-centric, such a session would encompass topics from a range of disciplines, and
be couched largely in a language (thermodynamics) that represents a common cross-disciplinary thread.
Possible topics include:
- Defining and quantifying the biological requirement for energy
- Understanding energetic constraints on origins of life chemistry, and defining the
possibilities for early energy-transducing systems in biology
- Understanding how energy is deposited and released during planet formation and evolution
- Identifying and quantifying possible energy sources for life, with specific emphasis
on subsurface environments (e.g., water-rock chemistry, Europan ice chemistry, “vent glow
photosynthesis”)
- Understanding what sorts of energy can be put to use in biology
- Understanding how energy availability and cycling shape the properties and activities of
biological systems
- Understanding whether biologically-mediated energy cycling generates diagnostic
biosignatures (e.g., redox biosignatures)
Assessing the need for a lander on Europa
Convener:
Kevin P. Hand
khand@stanford.edu
415-377-9053
PO Box 11102
Stanford, California 94309
The top exploration priority for the outer planets is a mission to Europa [1].
Much of the science motivating such a mission can, and will, be accomplished
utilizing instruments on board an orbiting spacecraft. However, the science
goals (as detailed in the Europa Geophysical Explorer, the Jupiter Icy Moons
Orbiter, and the Europa Orbiter science definition team reports [2]) also
specifically refer to the NASA Decadal Survey goal of identifying and mapping
'surface compositional materials with emphasis on compounds of astrobiological
interest'. One critical outstanding issue facing the community right now is
whether or not such a goal can be sufficiently satisfied without a lander on
the surface of Europa. If all of the science requirements can be satisfied
from orbit, then the mission is greatly simplified, costs can potentially be
reduced, and the push to a launch date could potentially be moved forward.
Conversely, a critical compromise in the science return for the sake of time
and money does not make sense either, especially if a range of viable options
exist for deploying a lander. During this symposium we will explore this issue
from both the science and engineering perspectives. Detection and characterization
of 'compounds of astrobiological interest' will be considered in the context of an
orbiter and a lander. Along with their presentations, all of the speakers have been
given specific questions related to the orbiter/lander debate that they must address
during their talks. Ultimately, we hope to engage the astrobiology community in
ongoing discussions that could serve as a guideline for optimizing the astrobiology
science return on any future Europa mission.
1. Outer Planets Assessment Group,
http://www.lpi.usra.edu/opag/meetings.html
2. See documents available at:
http://www.lpi.usra.edu/opag/resources.html
The environmental impact of life: redox changes from the microscale to
composition of the atmosphere and ocean
Conveners:
Andrey Bekker
Geophysical Laboratory, Carnegie Institution of Washington
a.bekker@gl.ciw.edu
Olivier Rouxel
Woods Hole Oceanographic Institution
Boswell Wing
McGill University
Redox conditions on a hierarchy of scales are controlled by, and influence, the presence of
life. Locally, redox conditions associated with biological activity might be faithfully
recorded by mineralogical or geochemical indicators and can serve as potential biosignatures.
On a global scale, the redox evolution of Earth’s atmosphere and ocean from an essentially
anoxic condition to the present oxygen-rich state are undoubtedly rooted in biological activity.
This redox transition has been the focus of recent astrobiological research, and its tempo
been refined through development and application of new analytical tools. As a whole,
however, comprehensive techniques for the study of Precambrian environmental redox conditions
are in their nascent stages. In particular, lessons learned from modern environments as
well as short periods of anoxia and euxinia in the Phanerozoic can guide in studies of the redox
state of Precambrian surface environments.
This symposium will bridge a gap between specialists using various tools to constrain the redox
state of the modern, Phanerozoic, and Precambrian ocean and atmosphere. Field, laboratory,
and theoretical studies that examine elemental, isotopic, and/or mineralogical redox indicators
are welcome. We look forward to submissions that attempt to bridge the scale gap between
biological control over microscale redox conditions and the global effects of life on composition
of the atmosphere and ocean. Studies that examine how non-biological processes can control
redox state at various scales are particularly encouraged to help define the conditions under
which local and global redox indicators might be taken as robust biosignatures.
Habitability on Mars: Surface vs. Subsurface
Convener:
Kathryn Fishbaugh
International Space Science Institute
Hallerstrasse 6
CH 3012 Bern, Switzerland
fishbaugh@issi.unibe.ch
+41 31 631 32 54
Mars clearly has abundant evidence on the global scale for water having been on the surface at some
point in the past. Additionally, the MER rovers have provided intriguing evidence for surface and
very near surface water at the outcrop scale. Thus, valley networks, possible, oceans, and ancient
lakes/playas are the big players at most meetings. This session will start with what is known about Martian
surface water and find out if those water-related features are/were habitable or if we need to delve a bit deeper.
Recently, the Mars Odyssey GRS discovered large concentrations of hydrogen within 1 meter of the surface
which may be ground ice. Additionally, surface water may be lost not only to the atmosphere but
also by seepage into the ground. Thus, there may be significant quantities of ice and/or water
within the martian upper crust. Protection from radiation and from large climatic changes make
the subsurface a potentially viable habitat. The subsurface is not only a possible place but
potentially the best place to find both current and past habitable environments on Mars.
This session will be organized as a type of debate between “Pro Surface” and “Pro
Subsurface”. We will hear from speakers as to why either is the best place to search for
life or even why a combination of the two is the best. The interdisciplinarity of this session lies in
the fact that astrobiologists and geologists must work together to assess the habitability of the
martian subsurface. Additionally, those who develop instrumentation to search for biosignatures
will be able to provide input on how surface and subsurface missions are different.
Potential Topics:
- Time scales of surface water: Was surface water ever present on the surface long enough to
support or initiate life?
- The question of flux: According to the Goldilocks Hypothesis, life needs sustained thermodynamic
disequilibrium and a constant supply of cations and anions – where can we find this on Mars?
- The best places for habitable environments in the subsurface in the past
- Currently habitable places in the subsurface
- Evolution of subsurface habitable environments through time: How have they changed?
Have they moved?
- Besides the obvious differences in platforms (rovers/landers vs. drills, etc.) what are the major
differences in two missions, one which focuses on the search for surface biosignatures and one which
focuses on the search for subsurface biosignatures?
- Ascertaining past habitat: If one drills and finds some type of biosignature, how does one
determine whether that life developed on the surface (and is now found further down the stratigraphic
column) or in the subsurface?
Elements of Life (Metallomics)
Conveners:
Ariel Anbar (ASU)
anbar@asu.edu
Jim Elser (ASU)
David Emerson (ATCC)
Astrobiologists are well acquainted
with the use of Fe and some other inorganic elements as electron donors and acceptors in microbial
respiration. As a result, a great deal of attention has been given to biological cycling of Fe, Mn
and other such elements. However, the importance of these and other elements extends beyond microbial
respiration because all known living systems require a highly non-random selection of chemical elements
as basic building blocks of cellular and extracellular structures. These include not only the macroelements
C, H, O, N, P and S but also a variety of micronutrient elements, mostly transition metals, which are active
components of metalloenzymes and other molecular structures. These elements comprise the "metallome".
Examples include Mg, Fe, Mn, Cu, Ni, Zn, and Mo, which are required co-factors for cell growth in many microorganisms.
The biochemical reactions in which these elements are involved are critical to the biogeochemical cycles of C, N and S.
The extended biological stoichiometry
of life and the use of inorganic elements in respiration are still poorly understood. The
implications are increasingly clear to biochemists and biogeochemists working in modern systems,
but have yet to be fully assimilated by the astrobiology community. Astrobiological consequences are
profound. At the most fundamental level, elemental abundances need to be considered when defining what
is a "habitable environment"; if the terrestrial experience is any guide, liquid water,
carbon and energy are clearly necessary but insufficient conditions for life. Equally important, the
course of evolution- especially the origin and evolution of key biochemical pathways- must be shaped
by elemental availability. Recognition that life requires a unique assemblage of elements also suggests
novel biosignatures; life may leave its fingerprints in the relative abundances of bioessential elements
in ancient sediments.
The proposed session would bring
together chemists, biochemists, ecologists, microbiologists and geoscientists working in these
areas with the goal of stimulating new research avenues in astrobiology.
Titan as a Prebiotic Chemical System
Conveners:
Patricia M. Beauchamp
Life Detection Science and Technology Office
Jet Propulsion Laboratory, M/S 180-604
Pasadena,.CA 91109
Patricia.M.Beauchamp@jpl.nasa.gov
Jonathan Lunine
Lunar and Planetary Laboratory
University of Arizona
Tucscon, AZ
jlunine@LPL.Arizona.edu
Mark Smith
Dept of Chemistry
University of Arizona
Tucson, AZ
msmith@u.arizona.edu
Titan, a natural satellite of Saturn, has intrigued many people since its discovery in 1655
by Dutch scientist Christiaan Huygens and with an atmosphere discovered by Gerard Kuiper in
1943. Nitrogen dominates the atmosphere, while methane is the second most abundant gas but there
is only ~10 ppm oxygen, as CO. Titan’s upper atmosphere is bathed in ultraviolet
photons from the Sun and particle radiation although the 95 K surface is very well shielded.
Consequently, methane in the stratosphere is broken apart by the UV and makes C2 and higher
hydrocarbons while methane condenses out in the ~70K troposphere. Titan is the second
largest moon in the solar system (after Jupiter’s Ganymede) and one of 3 moons with
bulk densities of 1.8 g/cm3, and radii ~ 2500 km (Ganymede, Callisto, and Titan) and one of
6 moons with roughly the same mass of silicates (Moon, Io, Europa, Ganymede, Callisto, Titan).
Is life a natural outcome of the formation and early evolution of planets?
If the origin of life came in a series of steps of increasing self-organization and chemical
specificity then we may see the progression from primordial chemical diversity to prebiotic
chemical selection to self-organizing chemical systems on Titan’s surface.
Cassini/Huygens has given us some new tantalizing data, but there is still much to learn.
The scope of this symposium is the past, present and future of Titan. This symposium will
examine Titan as a system with the goal of trying to better understand the
chemistry and potential for a prebiotic world. There are many questions to address.
How did Titan form? What was the origin of its atmosphere? What is the source of methane and the
timing of its outgassing to the surface? How much methane is present today in the surface-atmosphere
system of Titan? How thick are the deposits of organic materials, where are they in the Titan crust,
and what is the extent of their further chemistry beyond stratospheric photochemistry toward complex
organics of prebiotic interest? How has organic chemistry evolved over time on the surface of Titan,
and is the evolution progressive or cyclic? Was Titan's surface much warmer in the past and what
will conditions be like when the Sun becomes a red giant? What are the next appropriate steps
in the exploration of Titan in terms of mission design and instrument techniques?
Radio Astronomy: New Instruments And Their Importance For Astrobiology
Conveners:
Jill Tarter
Center for SETI Research
SETI Institute
515 N. Whisman Road
Mountain View, CA 94043
650-960-4555 voice
650-961-7099 fax
email: tarter@seti.org
Joseph Lazio, Ph.D.
Naval Research Laboratory
4555 Overlook Ave. SW
Washington, DC 20375-5351
voice: +1-202-404-6329
fax: +1-202-404-8894
Joseph.Lazio@nrl.navy.mil
Astrobiologists have recently become more and more
familiar with what optical and infrared observations of starforming regions, the interstellar medium, solar
system objects, and extrasolar planets can tell them. As a group we are somewhat less knowledgeable
about the potential for new insights from the realm of radio telescopes. There are a number of new
groundbased instruments under construction or planned for the future in this wavelength regime. Many of
them have already included areas of great interest to astrobiology in their 'science cases'. This session
would allow scientists from the telescope community to discuss the capabilities of these instruments to study the
formation of planets in protoplanetary disks, the creation, modification, and delivery of organic biomolecules,
the pristine relics of our own solar system, and even searches for extraterrestrial technologies. There
are still opportunities for astrobiologists to impact design decisions for some of these instruments to improve
their future relevance to astrobiology, and additional opportunities to form partnerships with scientists more
familiar with the existing instrumentation to conduct near-term, novel explorations of fundamental importance
to questions pertaining to the origin and evolution
of life here and elsewhere.
The Next Step for Astrobiology: Participation in Missions
Conveners:
Pamela Conrad, JPL, Conrad@jpl.nasa.gov,
Ph: 818-354-2114, and Victoria Meadows, CalTech, vsm@ipac.caltech.edu
Using a panel format, we will explore the relationship between astrobiology and NASA missions, including those already defined and the missions we would like to see. We will include principal investigators from missions, mission project managers and program scientists from NASA HQ.
Many of us do not even know that we can have an impact on what missions fly and on what science is returned from them. We also have access to mission science data from the Planetary Data Archive. Many major missions currently planned for NASA have ostensibly astrobiological goals, but is the astrobiology community aware of these missions and what is currently planned? Have we been engaged or polled for input into the design or science outcome for these missions? If our vision of astrobiology cannot be best accomplished by these missions, how do we design a mission that is an optimal experiment for astrobiology?
A) "How can astrobiology be better integrated into exploration missions
to the solar system and beyond?"
B) "How does integration of astrobiology benefit NASA's exploration
programs?"
C) How do we participate in science definition for future NASA missions?
D) How do we gain access to data from existing and previous NASA missions?
These and any other questions and comments are invited to the table for what is sure to
be a lively discussion on how to get our experiments out beyond the Earth.
Environmental Genomics in Analogue Environments
Conveners:
Brad Bebout
Exobiology Branch
NASA Ames Research Center
Mail Stop 239-4
Moffett Field, CA 94035-1000
Brad.M.Bebout@nasa.gov
(650) 604-3227 (office)
John F. Heidelberg
The Institute for Genomic Research
9712 Medical Center Drive
Rockville, MD 20850
jheidel@tigr.org
(301) 795-7584
Recognizing the emergent properties of the (dominantly microbial) life in various "extreme" environments on Earth as unambiguous biomarkers is a fundamental step in realizing our goal to detect life elsewhere. Microbial life in nature seldom exists as the pure cultures found in microbiology laboratories, but rather in complex assemblages of interacting microorganisms. While the metabolic capabilities of individual microorganisms (studied in pure culture) are impressive, it is in naturally-occurring microbial communities that staggering metabolic flexibility (and diversity) is observed as an emergent property of the intact ecosystem. What little that is known from laboratory studies of mixed microbial populations is that interactions between microorganisms are critical in determining these emergent properties. However, due to a lack of appropriate tools, very little is known about the relationship between the activities of individual microbes and the functioning of the intact ecosystem. In fact, we usually cannot even determine which particular microorganisms express a particular metabolic capability in natural assemblages. The inability to associate function with phylogeny (i.e., to discern who is doing what) places real constrains on our ability to interpret the record of evolution contained within the DNA of microorganisms growing in environments of profound interest to our search for life elsewhere.
Currently, genomic methodologies are being refined to overcome many of the limitations of both cultivation-based and PCR-based studies, allowing a more comprehensive approach for both gene discovery and hypothesis driven studies of noncultured microbial populations. Whole environmental DNA (eDNA) can be isolated and interrogated by sequencing approaches analogous to “pure-culture” genomics. Such methods, collectively called “metagenomics”, have now been used in studies from specific hypothesis-driven research (e.g., sequencing a fosmid that conferred a pigment to Escherichia coli) to exploratory projects, such as Iron Mountain, the Sargasso Sea, and comparative metabolism studies of environmental gene tags (EGT). Our proposed session will highlight the rapidly developing field of environmental metagenomics and its potential to unravel the molecular record of the co-evolution of life and planet contained in the DNA of naturally-occurring microbial communities, particularly those “analogue” environments thought to best represent targets in our search for life both within, and outside of our solar system.
Winning strategies for astrobiology communication, education and outreach
Linda Billings, Ph.D.
Research Associate
SETI Institute/Washington, DC
Ph. 202-479-4311
lbillings@seti.org
Krisstina Wilmoth
Assistant Director for Communications and Technology
NASA Astrobiology Institute
This symposium will brief astrobiologists on successful methods for communicating about science and engaging in science education and outreach with a broad spectrum of audiences. A growing number of scientists appear to be concerned about the need to improve and expand communications about astrobiology, across discipline boundaries within the field and with a broad range of non-expert audiences as well, encompassing organizations and individuals with a variety of interests and perspectives. This concern is warranted: with competition for funding intensifying, the spoils may go to those who can best explain the purpose and value of their work. In addition, public funding for research warrants public reporting on the research.
The symposium will consist of two panels. A panel on communication will feature science communication experts who will share relevant research in the field of science communication, best practices in science communication in general and astrobiology communication in particular, the range of audiences for communication about astrobiology, and the spectrum of interests and perspectives to be considered in planning communications. A second panel on education and public outreach will feature representatives of science funding agencies who will inform the astrobiology community about their vision for outreach educators, students, families, and the general public.
Weathering of Signs of Life on Planetary Bodies: Poster
Dr. John F. Cooper (Main Contact)
Space Physics Data Facility
Laboratory for Solar and Space Physics
Code 612.4
NASA Goddard Space Flight Center
8800 Greenbelt Road
Greenbelt, MD 20771
Phone: (301) 286-1193
Fax: (301) 286-1771
E-mail: John.F.Cooper@nasa.gov
Prof. Jere H. Lipps
Département Histoire de la Terre (CP 38)
Muséum National d'Histoire Naturelle
8, rue Buffon
F-75005 Paris, France
Office phone: 33-(0)1-40-79-30-40
Fax: 33-(0)1 40 79 35 80
Note: The above address information is effective until June 30, 2006.
E-mail: jlipps@berkeley.edu
Astrobiology is ultimately the search for signs of extraterrestrial life beyond the Earth in other planetary environments that may be hostile to survival of organic and inorganic signatures of life. The three other bodies of highest astrobiological potential (Mars, Europa, and Titan) all have extreme surface weathering environments that would adversely affect capabilities of remote sensing and in-situ instruments to detect and confirm presence of such signatures. Similarly, extreme geologic modifications over billions of years limit our ability to find signs of very early life on the Earth. Even the signs of more recent life at the Earth’s surface are affected by various weathering processes. Mars and Europa are unique in having surfaces exposed to intense energetic particle and ultraviolet irradiation, not unlike the early surface of Earth before the rise of atmospheric oxygen and the resultant ozone shield. Europa’s thin atmosphere arises primarily from Jovian magnetospheric ion sputtering and is highly oxidizing, much like the surface of Mars. The Mars Viking experience informs us that a chemically oxidizing surface environment cannot be ignored in planning experiments to search for organic signs of life. On Mars, Titan, and Earth, wind-driven erosion is a critical process, both degrading but also potentially exposing surface signs. In the absence of a substantial atmosphere, surfaces like that of Europa are continuously pelted by high-velocity micrometeoroids with highly erosive effects on surface materials. Cassini Huygens has revealed a Titan surface altered by flows of viscous liquid hydrocarbons, likely precipitated from the photochemically active atmosphere. Mars, Europa, and Titan may have subsurface liquid reservoirs occasionally flowing to the surface. Both Mars and Titan are now being explored by ongoing missions, and a future mission to Europa is now a top NASA priority. Any search for signs of life, whether on these other bodies or on Earth, requires an interdisciplinary approach to understanding and anticipating the weathering effects of the local atmospheric, surface, and subsurface environments on these signs. Presentations are solicited which improve our understanding how weathering processes potentially affect the search for signs of life on other planetary bodies, as well as on early Earth, and which help prepare for future astrobiology missions to these bodies.
The Impact of Gravity and Radiation on Extending Terrestrial
Life to the Rest of the Universe: Poster Link to Extinction Symposium
Eduardo Almeida, Nancy Searby, Ruth Globus
Contact information for E. Almeida: (650) 604-1772, E.Almeida@nasa.gov,
NASA ARC, MS/236-7, Moffett Field, CA 94035
The potential to extend terrestrial life throughout the universe depends on the survival of organisms in challenging planetary and extra-terrestrial environments. Gravity and radiation are two critical factors that are different in space and on other planets compared to Earth and are expected to exert selective pressures on the future evolution of life beyond the planet of origin. Investigators with broad experience in ground-based laboratory and spaceflight models will address a key question of astrobiology: how life can survive and adapt following departure from Earth. Some of the topics to be addressed in the symposium include results from both exposing unicellular and multi-cellular organisms to simulated and actual gravity and radiation conditions found in space and monitoring changes that ensue within and between generations.
This symposium will offer a historical perspective on how life fares beyond planet Earth, and will bring together scientists who have explored the effects of gravity and radiation using a variety of organisms, from single cells to whole organisms. Topics of discussion will include distinct biological problems in both prokaryotic and eukaryotic life forms ranging from molecular DNA repair and redox reactions to organismal reproductive and structural properties.
This symposium will foster interdisciplinary communication between experts focusing on gravity, radiation, and space biology from molecules to cells to organisms. Results from studies in these areas are central to astrobiology, and expand our understanding of the environmental limits of life throughout the universe.
The sustainability of liquid water on Mars, a fundamental Astrobiological question: Poster
Sanjoy M. Som
Dept. of Earth & Space Sciences
Center for Astrobiology and Early Earth Evolution
Box 351310
University of Washington
Seattle, WA 98105
USA
sanjoy@u.washington.edu
cell: 206-779-6629
The topic of whether or not Mars was a habitable environment suitable for the development of life as we know it is still extremely controversial. The question essentially boils down to whether or not water was stable on the surface for a sustained period of time, suitable to create enough of an environment for life to diversify and evolve microbially to an extent that a (cataclysmic? gradual?) change in the environment would not cause extermination of all strains of life but survival “of the fittest” in a yet undiscovered haven. The sustainability of water on the surface is a complex question that must be analyzed in an interdisciplinary manner to ensure that all the facets of this puzzle are covered, since no single science can hope to address all the relevant issues.
1.Geology: a) Is the absence of carbonate outcrops, despite an intense search effort, an indication of the lack of a sustained body of water? b) What different mechanisms exist to explain the layering found in many terrains?
2. Geomorphology and tectonics: a) Do the valley network exhibit morphological similarities to fluvial features on Earth? What quantitative measurements are possible? b) Does the presence of large shield volcanoes argue for a non-convecting mantle and thus a lack of tectonics? Is plate tectonics a necessity for life
3. Atmospheric Sciences: a) Arguments exist for fluvial activity up to the early Amazonian. Is that consistent with atmospheric model prediction? b) Temporary atmospheres: How can they occur, and for how long? c) Initial volatile distribution. Does the size of Mars argue for a different original volatile content that is different than Earth?
4. Biological sciences: a) What’s the big deal with water anyway? b) Niches: What potential environments could exist on Mars today and provide a local habitable environment? c) What about life trapped in ice? d) What biomarkers can we expect?
5. Glaciology: a) How did the polar caps evolve during periods of different obliquities? b) What are the physics of CO2 caps? Do they flow?
6. Astronomy: a) What surface process scientists must know about orbital parameter variation and their consequences?
7. Engineering: a) What technologies are available today for remote water detection or remote detection of past water (eg: sulfates, carbonates)?
8. Space Physics: e.g., Magnetic Field evolution and implication for depth of life
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