This PDF file contains the front matter associated with SPIE Proceedings Volume 7097, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.

Field Emission Scanning Electron Microscopy (FESEM) studies of recently obtained samples of Orgueil, Ivuna and Murchison meteorites have provided further evidence for the existence of indigenous filamentous microfossils embedded in the mineral matrix of CI1 and CM2 carbonaceous meteorites. Energy Dispersive X-ray Spectroscopy (EDS) spot data and 2-D elemental X-ray maps establish that the nitrogen and sulphur content of the forms found in the meteorites are dramatically different from modern prokaryotic and eukaryotic cells. These results are interpreted as providing additional evidence for the existence of a complex suite of indigenous microfossils in carbonaceous meteorites.

An investigation of the Early Proterozoic pillow lavas of South-Africa shows that the lava-water boundary is very interesting from the point of view of bacterial paleontology. In the pillow selvages corresponding to this boundary, forms such as bacteria (including cyanobacteria) developed. Cyanobacterial or bacterial mats formed and probably even such highly organized forms as eukaryotes existed.

The earliest evidence for amino acids on Earth is in Precambrian sedimentary rocks with varied metamorphic histories. Igneous rocks rarely contain such compounds, exceptions being those introduced via the migration of fluids into fractures subsequent to crystallization. Martian meteorites are excellent examples of ancient igneous rocks that apparently contain amino acids associated with minerals precipitated in rock fractures. The challenge has been to determine whether the organic compounds present in ancient terrestrial and extraterrestrial materials are indigenous and, if so, are representative of past life or pre-biotic synthesis. A summary of what is known to date about amino acids in ancient terrestrial and extraterrestrial materials is presented. Alternative approaches for distinguishing their origin(s) are discussed.

We have prepared solid silicates of various phenols and have studied them by the IR (infra-red) spectroscopy. Phenols are organic compounds that are important in biology. Only very recently phenols have been synthesized in prebiotic manner. They are formed under the hydrothermal conditions and also under the simulated conditions of the interstellar space. Solid phenol silicates, which we have prepared, are ideally suited for the preservation of phenols on prebiotic Earth and in space, and for their transportation in space. The reflectance IR spectra of phenol silicates were taken and are currently being analyzed. Our goal is to determine if phenols are entombed, covalently bound, or both, in respect to the silicate matrix. We have also prepared fluorescent phenol silicates.

The set of discovered Archaean organisms does not indicate anaerobic atmosphere as early as 3.5 Ga. The RNA-world must have existed at least at 3.9 GA and, likely, close to the beginning of degasification and appearance of water on the Earth surface. The earliest cellular organisms (membranes) also appeared before 4.0 Ga. Possibilities of evaluation of conditions on the Earth's surface are under the consideration of both geological-geochemical and possibly mainly paleontological data. The important element in the analysis of the Earth conditions is the level of organisms organization presented in the paleontological record, because it is connected with the existence of peculiar abiogenic conditions, such as temperature, amount of oxygen, amount of water etc.

Lipid biomarker analyses of sedimentary organic matter from a marine Triassic-Jurassic (T-J) section at Queen Charlotte Islands, British Columbia reveal significant bacterial activity and microbial community changes that coincide with faunal extinctions across the T-J boundary. Bacterial activity is indicated by the 25-norhopane biodegradation index (25-norhopanes / 25-norhopanes+regular hopanes). Microbial community changes is revealed by variations in relative abundance of 2-methylhopane which is mainly generated from cyanobacteria. The 2-methylhopane index (2-methyl hopane/ C₃₀ hopane + C₂₉ 25-norhopane) increases above the radiolarian based T-J boundary, and coincides with changes in the 25-norhopane index. The data reveal a complex microbial event involving both autotrophic and heteorotrophic bacteria responding to variations in allochthonous organic matter and nutrient supply.

In our search for the definition of life that will be relevant for astrobiology, we consider various entities that have some but not all of their features in common with the fully developed functioning life. We name these entities "life forms". Examples include viruses, spores, and partners in syntrophy (metabolically interdependent relationships). We introduce meaningful categories into which these life forms fit, and offer a definition of life in which they are included. Our suggested working definition of life is that life is a chemical phenomenon which occurs in space and time as a succession of life forms which combined have a potential to metabolize, reproduce, interact with the environment, including other life forms, and are the subject to natural selection.

The stable isotopic compositions of Late Pleistocene and Holocene cave deposits (speleothems) are valuable proxies for high-resolution climate reconstructions on Earth, in particular with respect to changes in vegetation, temperature, atmospheric composition, and monsoonal precipitation. On the basis of U-Th dating and annual growth bands, researchers have shown that many speleothems can grow continuously for thousands to hundreds of thousands of years. Depending on the growth rate of a given speleothem, and its sensitivity to environmental changes on the surface, it may record climatic shifts on timescales ranging from weeks to years. This has made modern speleothems particularly useful for applications ranging from paleotempestology to studies of glacial-interglacial transitions. It stands to reason, then, that ancient speleothems might hold valuable information about climatic change in the deep geologic past - at resolutions that have been previously unattainable using other materials (e.g. paleosols). Here we report carbon and oxygen isotopic signatures obtained from an Early Permian flowstone that was extracted from a shallow paleocave in Oklahoma. We interpret the stable isotope data to reflect progressive aridification and devegetation, possibly as a result of CO2 forcing. This interpretation is consistent with independent paleoclimatic data from coeval sediments in the region, and is also broadly consistent with similar records from modern, low-latitude speleothems. The fact that isotopic signatures are preserved in speleothems up to a few hundred million years old indicates that it might be possible to retrieve similar climatic data from ancient carbonate deposits elsewhere in the solar system.

The astrobiology-related activities in the National Astronomical Observatory of Japan (NAOJ) is reported. The 45m radio telescope of the NAOJ was used to search for the interstellar glycine without success, concluding that the former claim on the detection of interstellar glycine has not been confirmed. Future observations by ALMA would clarify the existence of glycine in space. The Okayama Astrophysical Observatory of the NAOJ has been used to detect ten extrasolar planets. The Subaru telescope has also been used, under international collaborative program, to search for extrasolar planets, leading to detection of two planets. A unique trial to search for extrasolar planets by using low frequency radio data was conducted without success, however, such a method would be a basis toward radio searches by future sensitive radio astronomy instruments such as SKA and LOFAR. NAOJ has a project to search for extraplanets by a highly sensitive coronagraph. This project has also designing the Japanese Terrestrial Planet Finder for future space-based search for the Earth-type planets.

We present instrument concepts for in-situ reflectance spectroscopy over a spatial resolution range from several meters to tens of μm. These have been adapted to the low mass and power requirements of rover or similar platforms. Described are a miniaturized imaging spectrometer for rover mast, a combined mast and arm point spectrometer, and an imaging microspectrometer for the rover arm.

In order to better understand the properties of exoplanetary systems, the Cosmic Vision mission "PLAnetary Transits and Oscilliations of stars" (PLATO) will detect and characterise exoplanets using their transit signature in front of a large sample of bright stars as well as measuring the seismic oscillations of the parent star of these exoplanets. PLATO is a potential mission of the European Space Agency's Science programme Cosmic Vision 2015-2025, with a planned launch by the end of 2017. The mission will be orbiting the Sun-Earth second Lagrangian point, which provides a stable thermal environment and maximum uninterrupted observing efficiency. The payload will consist of a number of individual catadioptric telescopes, covering a large field-of-view on the sky. It will allow for continuous observation of predetermined star fields in order to detect many exoplanetary systems as well as smaller exoplanets with longer orbital periods. Such performance is achieved by high time-resolution, high precision, and high duty-cycle visible photometry using catadioptric telescopes with CCD detectors. In order to fulfill the specific science requirements, special attention is being paid to the opto-mechanical design of the payload, in order to maximize the field-of-view and throughput of the optical system, while minimizing the image distortion, mass and volume of each telescope to ensure compatibility with the launcher's maximum payload capability. Ground-based observations will complement the observations made by PLATO to allow for further exoplanetary characterization. The paper provides a summary of the preliminary results achieved by the ESA internal pre-assessment study.

Analog examples of what primeval oceans might have looked in the Precambrian are probably extant in various regions and at various size scales in present day oceans albeit they have not been sufficiently recognized and/or studied. The Eastern Boundary Current Ecosystems (EBCEs), with their characteristic high productivity-inducing coastal upwelling events, their extensive and intensive anoxic/hypoxic water column and methane and sulfide-rich benthic environment, appear to represent such analogs. Moreover, recent studies have shown that they possess diverse anaerobic prokaryotic communities of mat-forming large multi-cellular filamentous bacteria similar to fossils found in Archean and Proterozoic rocks. Observations in the Bay of Concepcion, central Chile (~36°S), inserted in the second most productive EBCE of the world, suggests that given similar oceanographic dynamics, past oceans may have presented different predominant colorations after the first probable "red" color of the reduced iron-rich Archean ocean and prior to the present day "blue" color. In this coastal ecosystem a "black" coloration has been observed to form as the result of the floating to the surface layer of sulfide-blackened benthic detritus together with chunks of microbial mats, and a "milky to turquoise" coloration resulting from different concentrations of colloidal, nano-sized particles which may include elemental sulfur and/or microorganisms. If the present is the key to the past we posit that "black" color oceans could have existed during the Proterozoic "Canfield sulfidic ocean" followed by "milky to turquoise" colored oceans during later stages of the Proterozoic. Meso-scale examples of "milky" and "turquoise" portions of oceans, caused by elemental sulfur from oxidized hydrogen sulfide eruptions, have been described from off Namibia and there appear to also exist elsewhere. Examples of "black" oceans have apparently not been reported but the name of the Black Sea, the largest permanent anoxic basin on Earth, suggests that at some point in time it may have been black, at least locally and/or for short periods, prompting the name. We conclude suggesting that analogous to the present "Blue Planet" denomination, in the past our Earth could possibly have deserved the successive names of "Red", "Black" and "Milky-Turquoise" Planet.

A number of photosynthetic systems have evolved on Earth to harvest various portions of the available spectrum from its G2 star. Currently, the number of confirmed extrasolar planets approaches 300, although many are in orbits well outside their habitable zone. This largely results from an observational bias that tends to more easily spot these "hot Jupiters," but increasingly more Earth-like extrasolar planets are detected. The spectral classes of the stars supporting these planets are generally well-identified, permitting some basic assumptions on the inner and outer habitable zone radii. We can also make some assumptions on the spectrum of photon energy available for potential photosynthesis on these planets, allowing for local atmospheric effects. The absorption spectra of terrestrial photosynthetic systems, both naturally evolved, and artificially created, are matched to the anticipated spectra on extrasolar planets. Further consideration is given to the cooler M class stars, whose large number and long life enhance the likelihood of photosynthesis evolving.

We have investigated the feasibility of the PCR amplification of the 16S rRNA genes from eubacteria and Archea on samples collected on Whatman FTA filters from Schirmacher Oasis for the study of culture-independent analysis of the microbial diversity. Both conventional PCR and real-time Taqma^TM PCR successfully amplified the targeted genes. A number of diverse groups of psychrotolerant microorganisms with various pigments have been isolated when cultured on agar medium. 16S rRNA gene analysis of these isolates helped us to identify closest taxonomic genus Pseudomonas, Frigoribacterium, Arthrobacter, Flavobacterium, and Janthinobacterium. It is possible that the pigments play protective role from solar UV radiation, which is prevalent in Antarctic continent especially during Austral summer months. Study of the expression of cold adaptive protein CapB and ice-binding protein IBP using western blots showed positive detection of both or either of these proteins in 6 out of 8 isolates. Since the CapB and IBP protein structure greatly varies in microorganisms, it is possible that the 2 isolates with negative results could have a different class of these proteins. The expression of the CapB and the IBP in these isolates suggest that these proteins are essential for the survival in the Antarctic cold and subzero temperatures and protect themselves from freeze-damage. The current study provided sufficient data to further investigate the rich and diverse biota of psychrotolerant extremophiles in the Antarctic Schirmacher Oasis using both culture-independent and culture-based approaches; and understand the mechanisms of cold tolerance.

Among the most interesting targets for Astrobiology research are the polar ice caps and the permafrost of Mars and the ice and liquid water bodies that may lie beneath the frozen crusts of comets, the icy moons of Jupiter (Europa, Io and Ganymede) and Saturn (Titan and Enceladus). The permanently ice-covered lakes of Antarctica, such as Lake Vostok and Lake Untersee, provide some of the best terrestrial analogues for these targets. The 2008 International Tawani Schirmacher Oasis/Lake Untersee Expeditions have been organized to conduct studies of novel microbial extremophiles and investigate the biodiversity of the glaciers and ice-covered lakes of Dronning Maud Land, East Antarctica. This paper describes the preliminary analysis of the anaerobic microbial extremophiles isolated from samples collected during the 2008 International Schirmacher Oasis Antarctica Reconnaissance Expedition. These samples showed great diversity of psychrophlic and psychrotolerant bacteria. Six new anaerobic strains have been isolated in pure cultures and partially characterized. Two of them (strains ARHSd-7G and ARHSd-9G) were isolated from a small tidal pool near the colony of African Penguins Spheniscus demersus. Strain ARHSd-7G was isolated on mineral anaerobic medium with 3 % NaCl, pH 7 and D-glucose, it has motile, vibrion shape cells, and is Gram variable. Strain ARHSd-9G grew on anaerobic, alkaline medium with pH 9 and 1 % NaCl at 3°C. The substrate was D-glucose supplemented with yeast extract (0.05 %). Cells of strain ARHSd-9G had morphology of straight or slightly curved elongated rods and demonstrated unusual optical effects under dark-field visible light microscopy. The cells were spore-forming and Gram positive. From the mat sample collected near Lake Zub, the new strain LZ-3 was isolated in pure culture at 3°C. Strain LZ-3 was anaerobic and grew on 0.5 % NaCl mineral medium with Dglucose as a substrate. The gram positive cells were spore-forming. They exhibited a distinctive morphology of large rods with rounded ends and size 1x10 μm. From the sample of ice sculpted by wind and melting by solar heating, containing many entrained black rocks collected near Lake Podprudnoye the new strain ISLP-22 was isolated in pure culture. The cells of this strain had vibrion shape and were spore-forming and had "baseball bat" shapes). This culture preferred 0.1 % NaCl mineral anaerobic medium and grew rapidly at 3 °C. Currently, all strains are under physiological study and phylogenetic analysis.

To search for extraterrestrial life surrogate extreme environments on Earth have been chosen for investigation. An example of a surrogate site is the Canadian subpermafrost. Investigations into microbial communities occurred by access fracture borehole water in the Lupin gold mine, and drill rock cores and drilling waters in the High Lake region of Nunavut, Canada. Membrane lipid analyses uses GC/MS and HPLC/ES/MS/MS to provide estimates of biomass, phospholipid (PLFA) and respiratory quinone composition, and compositional changes related to membrane stress caused by nutritional limitations or exposure to toxic conditions. Lupin fracture borehole waters were collected from 800 to 1200 meters, while the High Lake rock cores were collected from 335 to 535 meters. Biomass estimates based on PLFA ranged from 0.25 to 22 pmol L^-1 for the Lupin waters. High Lake drill waters had biomass that ranged from below detection limits (bdl) to 595 pmol/ml, while rock core samples had biomass estimates ranging from bdl to 32 pmol g^-1. PLFA profiles revealed the presence of both Gram +/- bacteria and sulfatereducing bacteria. Specific PLFA ratios indicate that the bacterial communities were physiologically stressed. Menaquinones were the most abundant but varied in the dominant isoprene units between the two sites. Ubiquinone to menaquinone ratio indicated that these samples have been anoxic for a long time. Methods to detect life signatures at surrogate sites on Earth will be critical for assessing extraterrestrial life. Currently, the membrane lipid analyses provide additional information not easily provided by other molecular techniques.

The recognition of iron microbial mats in terrestrial environments is of great relevance for the search for extraterrestrial life, especially on mars where significant iron minerals were identified in the subsurface. Most researches focused on very ancient microbial mats (e.g. BIFs) since they formed on Earth at a time where similar conditions are supposed to have prevailed on Mars too. However, environmental proxies are often difficult to use for these deposits on Earth which, in addition, may be heavily transformed due to diagenesis or even metamorphism. Here we present modern and phanerozoic iron microbial mats occurrences illustrating the wide variety of environments in which they form, including many marine settings, ponds, creeks, caves, volcanoes, etc. Contrarily to their Precambrian counterparts, Modern and Phanerozoic deposits are usually less affected by diagenesis and the environmental conditions likely to be better constrained. Therefore, their investigation may help for the search for morphological and geochemical biosignatures (e.g. iron isotopes) in ancient iron microbial occurrences on Earth but also on other Planets. In particular, many of the case studies presented here show that microstromatolithe-like morphologies may be valuable targets for screening potential biosignatures in various rock types.

Numerous chemical additives lower the freezing point of water, but life at sub-zero temperatures is sustained by a limited number of biological cryoprotectants. Antifreeze proteins in fish, plants, and insects provide protection to a few degrees below freezing. Microbes have been found to survive at even lower temperatures, although, with a few exceptions, antifreeze proteins are missing. Survival has been attributed to external factors, such as high salt concentration (brine veins) and adhesion to particulates or ice crystal defects. Teichoic acid is a phosphodiester polymer ubiquitous in Gram positive bacteria, composing 50% of the mass of the bacterial cell wall and excreted into the extracellular space of biofilm communities. We have found that when bound to the peptidoglycan cell wall (wall teichoic acid) or as a free molecule (lipoteichoic acid), teichoic acid is surrounded by liquid water at temperatures significantly below freezing. Using solid-state NMR, we are unable to collect ³¹P CPMAS spectra for frozen solutions of lipoteichoic acid at temperatures above -60 °C. For wall teichoic acid in D₂O, signals are not seen above -30 °C. These results can be explained by the presence of liquid water, which permits rapid molecular motion to remove ¹H/³¹P dipolar coupling. ²H quadrupole echo NMR spectroscopy reveals that both liquid and solid water are present. We suggest that teichoic acids could provide a shell of liquid water around biofilms and planktonic bacteria, removing the need for brine veins to prevent bacterial freezing.

Rapid discovery of the distribution and relative abundance of organic material without sample destruction or the expenditure of irreplaceable resources is one of the primary requirements for exploration of novel extreme environments both in remote locations on Earth and on the Mars regolith. A wide variety of organic and biogenic molecular targets including polycyclic aromatic hydrocarbons, aromatic amino acids, nucleic acids, photosynthetic pigments, and critical metabolic components such as flavin adenine dinucleotide and nicotinamide adenine dinucleotide exhibit strong, distinctive fluorescent signatures following excitation by ultraviolet (UV) light sources. These fluorescence signatures are easily imaged with camera systems currently employed on Mars rovers and imaging equipment available during human or robotic exploration of remote extreme environments on Earth. In this paper we discuss recent results with epifluorescent imaging of organic and biological targets using filter bands comparable to those available to ExoMars and review plans for epifluorescence surveys of the Dry Valleys of Eastern Antarctica including the Schirmacher Oasis and the perennially ice-covered, merimictic, oligotrophic Lake Untersee.

We have characterized function related DNA sequences of various organisms using informatics techniques, including fractal dimension calculation, nucleotide and multi-nucleotide statistics, and sequence fluctuation analysis. Our analysis shows trends which differentiate extremophile from non-extremophile organisms, which could be reproduced in extraterrestrial life. Among the systems studied are radiation repair genes, genes involved in thermal shocks, and genes involved in drug resistance. We also evaluate sequence level changes that have occurred during short term evolution (several thousand generations) under extreme conditions.

Diatom bioactivity has been reported to be responsible for about 20% of carbon fixation globally and together with other photosynthetic organisms, the bioactivity can be monitored via satellite ocean imaging. The bioinformatics embedded in the nucleotide fluctuations of photosynthesis and bio-silicate genes in diatoms were studied. The recently reported phosphoenolpyruvate carboxylase PEPC1 and PEPC2 C4-like photosynthesis genes in Phaeodactylum tricornutum were found to have similar fractal dimensions of about 2.01. In comparison, the green alga Chlamydomonas reinhardtii PEPC1 and PEPC2 genes have fractal dimensions of about 2.05. The PEPC CpG dinucleotide content is 8% in P. tricornutum and 10% in C. reinhardtii. Further comparison of the cell wall protein gene showed that the VSP1 gene sequence in C. reinhardtii has a fractal dimension of 2.03 and the bio-silica formation silaffin gene in Thalassiosira pseudonana has a fractal dimension of 2.01. The phosphoenolpyruvate carboxylase PPC1 and PPC2 in T. pseudonana were found to have fractal dimensions and CpG dinucleotide content similar to that of P. tricornutum. The fractal dimension of the dnaB replication helicase gene is about 1.98 for both diatoms as well as for the alga Heterosigma akashiwo. In comparison, the E. coli dnaB gene has a fractal dimension of about 2.03. Given that high fractal dimension and CpG dinucleotide content sequences have been associated with the presence of selective pressures, the relatively low fractal dimension gene sequences of the two unique properties of Earth-bound diatoms (photosynthesis and bio-silica cell wall) suggests the potential for the development of high fractal dimension sequences for adaptation in harsh environments.

The Witwatersrand Supergroup is a 2.9-billion-year-old formation of low permeability sandstone and shale with minor volcanic units and conglomerates with an ambient rock temperature of approximately 60°C. Thermus scotoductus SA-01 was isolated from fissure water at a depth of 3.2 kmbls in a South African gold mine and it shows the ability to reduce a variety of heavy metals under anaerobic conditions. It has been postulated that such microorganisms could play an important role in nutrient and metal cycling within the subsurface. Recently, our studies indicate that the cycling of metals could also occur under aerobic conditions and not only by the action of redox active enzymes, but other diverse metabolic proteins as well. In this study the capability of specific proteins to interact with metals is elucidated. Using Thermus SA-01 and its now completed genome sequence, metal reduction is studied through classic proteomic- and genomic methods. Finally we identify thermostable enzymes responsible for the transformation of various metals (Iron, Chrome, Uranium, Gold, etc) and discuss that reduction occurs via the serendipitous action of enzymes with other primary physiological functions, some of which are classical catabolic enzymes and anabolic proteins. This paper discusses the use of a ubiquitous enzyme/protein performing more than one function, possibly detoxifying the environment and using moonlighting as resource to decrease cellular energy requirements rather than elaborate metabolism in the subsurface.

In early 2006, unusual algal blooms of two species occurred in the Salton Sea, a large salt lake in southern California. In mid-January local residents reported bioluminescence in the Sea. Starting in February, large rafts of long-lasting foam, also bioluminescent, were observed as well. Microscopy investigations on water and sediment samples collected in March showed the marine dinoflagellate, Alexandrium margalefii, and the prymnesiophyte, Prymnesium sp., both previously unreported in the Salton Sea, to be abundant. Bioluminescence and foam production continued through March. Other dinoflagellate species, recorded during earlier studies, were rare or not detected during these blooms. Despite the fact that many Alexandrium species are known paralytic shellfish poison (PSP) producers, preliminary saxitoxin tests on this population of A. margalefii were negative. Previous reports on A. margalefii do not mention bioluminescence. It appears that the foam was caused by the Prymnesium sp. bloom, probably via protein-rich exudates and lysis of other algal cells, and its glow was due to entrained A. margalefii. This is the first report of A. margalefii in U.S. waters and the first report of it in a lake.

A nucleotide sequence can be expressed as a numerical sequence when each nucleotide is assigned its proton number. A resulting gene numerical sequence can be investigated for its fractal dimension in terms of evolution and chemical properties for comparative studies. We have investigated such nucleotide fluctuation in the RecA repair gene of Psychrobacter cryohalolentis K5, Psychrobacter arcticus 273-4, and Psychrobacter sp. PRwf-1. The fractal dimension was found to correlate with the gene's operating temperature with the highest fractal dimension associated with P. cryohalolentis K5 living at the low temperatures found in Siberian permafrost. The CpG dinucleotide content was found to be about 5% for the three species of Psychrobacters, which is substantially lower than that of Deinococcus radiodurans at about 12%. The average nucleotide pair-wise free energy was found to be lowest for Psychrobacter sp. PRwf-1, the species with the lowest fractal dimension of the three, consistent with the recent finding that Psychrobacter sp. PRw-f1 has a temperature growth maximum of 15-20°C higher than P. arcticus 273-4 and P. cryohaloentis K5. The results suggest that microbial vitality in extreme environments is associated with fractal dimension as well as high CpG dinucleotide content, while the average nucleotide pair-wise free energy is related to the operating environment. Evidence that extreme temperature operation would impose constraints measurable by Shannon entropy is also discussed. A quantitative estimate of an entropy-based measure having the characteristics of a mechanical pressure shows that the Psychrobacter RecA sequence experiences lower pressure than that of the human HAR1 sequence.

Cultures of the methane-producing archaea Methanosarcina, have recently been isolated from Alaskan sediments. It has been proposed that methanogens are strong candidates for exobiological life in extreme conditions. The spatial environmental gradients, such as those associated with the polygons on Mars' surface, could have been produced by past methanogenesis activity. The 16S rRNA gene has been used routinely to classify phenotypes. Using the fractal dimension of nucleotide fluctuation, a comparative study of the 16S rRNA nucleotide fluctuation in Methanosarcina acetivorans C2A, Deinococcus radiodurans, and E. coli was conducted. The results suggest that Methanosarcina acetivorans has the lowest fractal dimension, consistent with its ancestral position in evolution. Variation in fluctuation complexity was also detected in the transcription factors. The transcription factor B (TFB) was found to have a higher fractal dimension as compared to transcription factor E (TFE), consistent with the fact that a single TFB in Methanosarcina acetivorans can code three different TATA box proteins. The average nucleotide pair-wise free energy of the DNA repair genes was found to be highest for Methanosarcina acetivorans, suggesting a relatively weak bonding, which is consistent with its low prevalence in pathology. Multitasking capacity comparison of type-I and type-II topoisomerases has been shown to correlate with fractal dimension using the methicillin-resistant strain MRSA 252. The analysis suggests that gene adaptation in a changing chemical environment can be measured in terms of bioinformatics. Given that the radiation resistant Deinococcus radiodurans is a strong candidate for an extraterrestrial origin and that the cold temperature Psychrobacter cryohalolentis K5 can function in Siberian permafrost, the fractal dimension comparison in this study suggests that a chemical resistant methanogen could exist in extremely cold conditions (such as that which existed on early Mars) where demands on gene activity are low. In addition, the comparative study of the Methanococcoides burtonii cold shock domain sequence has provided further support for the correlation between multitasking capacity and fractal dimension.

It is known that comets are aging very rapidly on cosmic scales, because they rapidly shedmass. The processes involved are (i) normal activity-sublimation of ices and expulsion of dust from discrete emission sources on and/or below the surface of a comet's nucleus, and (ii) nuclear fragmentation. Both modes are episodic in nature, the latter includes major steps in the comet's life cycle. The role and history of dynamical techniques used are described and results on mass losses due to sublimation and dust expulsion are reviewed. Studies of split comets, Holmes-like exploding comets, and cataclysmically fragmenting comets show that masses of 10 to 100 million tons are involved in the fragmentation process. This and other information is used to investigate the nature of comets' episodic aging. Based on recent advances in understanding the surface morphology of cometary nuclei by close-up imaging, a possible mechanism for large-scale fragmentation events is proposed and shown to be consistent with evidence available from observations. Strongly flattened, pancake-like shapes appear to be required for comet fragments by conceptual constraints. Possible end states are briefly examined.

The salt geochemistry of Mars is predicted as an extrapolation of the salt geochemistry of the Dry (ice-free) Valleys in Antarctica. It is hard to escape the implication that there must be calcium/magnesium brine lakes in the enclosed drainage basins associated with the Northern Ice Cap. Because of the extreme cold these lakes will have acquired an ice cover. At the interface between the ice cover and the brine, one may find a thin layer of relatively fresh water. This might be the best and easiest place to look for Martian life.

Conceptions of thickness of frost rock and cryolithosphere of Mars were considered by R.Kuzmin (Kuzmin 1983), M. Krass and V.Merzlikin (Krass & Merzlikin 1990), S.M.Clifford and T.J.Parker (Clifford & Parker 2001). Mostly the evaluations of martian cryolithosphere thickness were carried out on the base of model of stable temperature field. The thickness of frost rock massive H_m was found by the profile of stationary distribution of temperature with the depth for one and two-layer lithological model. We input average annual temperature of surface, temperature of phase change of H₂0 and temperature of heat transfer and value of heat flux to the lower boarder of permafrost. The difference was in the choosing of parameters: average values of heat conductivity coefficient of upper layers, values of heat flux from inside, average temperature of surface, profile model.

Stromatolites offer a unique fossil record across 3.5 Ga of microbial community evolution within the context of an evolving Earth. Our interest is in developing quantitative metrics to follow the evolution of stromatolite morphological complexity. Adopting the canonical definition of complexity as the emergence of previously unseen properties in a dynamic phenomenon, we have previously proposed in these proceedings that laminations are the defining emergent property of stromatolites and we have employed a set of statistical information metrics to quantify laminae complexity in two spatial dimensions. We now demonstrate computer x-ray tomography of stromatolites and discuss the advantages of this 3D volume density distribution technique for characterizing stromatolite samples. CT imaging makes it possible to create a virtual stromatolite, enabling both research and educational efforts previously hampered by the costs of obtaining, preparing, and distributing precious Archean stromatolite fossils. We discuss recent advances in instrument miniaturization making it feasible to provide nondestructive 3D density and elemental abundance information on endolithic geobiological targets during future manned and unmanned missions to Mars.

The red cells found in the red rain in Kerala, India are now considered as a possible case of extraterrestrial life form. These cells can undergo rapid replication even at an extreme high temperature of 300 deg C. They can also be cultured in diverse unconventional chemical substrates. The molecular composition of these cells is yet to be identified. This paper reports the unusual autofluorescence characteristic of the cultured red rain cells. A spectrofluorimetric study has been performed to investigate this, which shows a systematic shift of the fluorescence emission peak wavelength as the excitation wavelength is increased. Conventional biomolecules are not known to have this property. Details of this investigation and the results are discussed.

We have found that the principles of dialetheism, which state that some contradictions (typically at the limits of a system) may be true, and which amply demonstrate the limits of thought and conception, can be valuable in sorting out and clarifying various astrobiological problems. Examples include the classification of viruses as alive or not alive, and the description of the abiotic-to-biotic transition. We also note the limits of our conception of the extraterrestrial life.

We present Raman spectroscopy analysis on laboratory and field sample analysis on several expeditions. Our measurements in mineral and organic composition have demonstrated that both mineral and organic species in low concentrations can be identified with Raman spectroscopy with no sample preparations and without instrument probe contact to the samples. Our laboratory studies on cyanobacterial biomat, and Mojave Desert rocks have demonstrated the promising potential for Raman spectroscopy as a nondestructive, in situ, high throughput detection technique, as well as a desirable active remote sensing tool for future planetary and space missions.

Three recent discoveries support the existence of an extra-planetary, cometary biosphere that is capable of spanning the galaxy: 1) the discovery of ancient cyanobacterial fossils on carbonaceous chondrites, which are widely believed to be extinct comets, 2) the observations and theory that all short-period comets have irreversibly differentiated by melting and undergo periodic remeltings, and, 3) the observation that comets can accrete inner solar-system material, including spores from other infected comets. While no direct observation of sub-cellular, fossilized viruses exist, their ubiquity and proximity with cyanobacteria suggest that the proposed cometary biosphere also carries a full complement of bacteriophages. Recent work transcribing viral DNA of bacteriophages reveals an active horizontal transfer of genes though a vector that doesn't itself benefit from the genes. Thus the cometary biosphere is capable of transporting genes throughout the galaxy that are not themselves expressed in space, suggesting that evolution may occur not just in time, but in space as well, making the Earth and its history less significant for a cosmological theory of evolution. That is, evolution is driven not by innovation, but by communication, albeit at a slow cometary speed and the transfer of a life ecosystem through a low bitrate channel can be modelled as a bootstrap process. Thus cometary evolution suggests that the history of earth represents the spatial relativity of a bootstrap process at the speed of life.