Proceedings Volume 7441

Instruments and Methods for Astrobiology and Planetary Missions XII

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Proceedings Volume 7441

Instruments and Methods for Astrobiology and Planetary Missions XII

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Volume Details

Date Published: 11 September 2009
Contents: 11 Sessions, 40 Papers, 0 Presentations
Conference: SPIE Optical Engineering + Applications 2009
Volume Number: 7441

Table of Contents

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Table of Contents

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  • Microfossils and Biomarkers in Meteorites and Ancient Terrestrial Rocks I
  • Microfossils and Biomarkers in Meteorites and Ancient Terrestrial Rocks II
  • Instrumentation for Astrobiology
  • Mars, Venus, and Astrobiology I
  • Mars, Venus, and Astrobiology II
  • Microbial Extremophiles I
  • Microbial Extremophiles II
  • Astrobiology and Planetary Protection
  • X-Ray, UV, Visible, and IR Instrumentation for Planetary Missions
  • Poster Session
  • Section
Microfossils and Biomarkers in Meteorites and Ancient Terrestrial Rocks I
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Life on Mars: new evidence from martian meteorites
David S. McKay, Kathy L. Thomas-Keprta, Simon J. Clemett, et al.
New data on Martian meteorite 84001 as well as new experimental studies show that thermal or shock decomposition of carbonate, the leading alternative non-biologic explanation for the unusual nanophase magnetite found in this meteorite, cannot explain the chemistry of the actual martian magnetites. This leaves the biogenic explanation as the only remaining viable hypothesis for the origin of these unique magnetites. Additional data from two other martian meteorites show a suite of biomorphs which are nearly identical between meteorites recovered from two widely different terrestrial environments (Egyptian Nile bottomlands and Antarctic ice sheets). This similarity argues against terrestrial processes as the cause of these biomorphs and supports an origin on Mars for these features.
Microfossils in carbonaceous meteorites
Microfossils of large filamentous trichomic prokaryotes have been detected during in-situ investigations of carbonaceous meteorites. This research has been carried out using the Field Emission Scanning Electron Microscope (FESEM) to examine freshly fractured interior surfaces of the meteorites. The images obtained reveal that many of these remains are embedded in the meteorite rock matrix. Energy Dispersive X-Ray Spectroscopy (EDS) studies establish that the filamentous microstructures have elemental compositions consistent with the meteorite matrix, but are often encased within carbon-rich electron transparent sheath-like structures infilled with magnesium sulfate. This is consistent with the taphonomic modes of fossilization of cyanobacteria and sulphur bacteria, since the life habits and processes of these microorganisms frequently result in distinctive chemical biosignatures associated with the properties of their cell-walls, trichomes, and the extracellular polymeric substances (EPS) of the sheath. In this paper the evidence for biogenicity presented includes detailed morphological and morphometric data consistent with known characteristics of uniseriate and multiseriate cyanobacteria. Evidence for indigeneity includes the embedded nature of the fossils and elemental compositions inconsistent with modern bio-contaminants.
Volcanic glasses as habitat for microfossils: evidence from the early Paleoproterozoic pillow lavas of Karelia and their modern analogues in the Mid-Atlantic Ridge
M. M. Astafieva, A. Yu. Rozanov, E. V. Sharkov, et al.
Microbial complexes were identified in the volcanic glasses from the ancient (2.4-Ga-old basaltic pillowlavas of Karelia) and modern (pillow lavas of Mid-Atlantic ridge) volcanic rocks. It was shown that that their microbial colonization is likely to occur by the same mechanism. Thus, well preserved pillow lavas, which occupy a spacious fields in the Archean and Early Paleoproterozoic greenstone belts, are promising object for search of the earliest traces of life on Earth.
Microfossils and Biomarkers in Meteorites and Ancient Terrestrial Rocks II
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Partial racemization of amino acids in meteorites: implications for their possible modes of origin
The structural proteins of all living organisms consist of twenty amino acids, nineteen of which have asymmetric centers. In living organisms these amino acids occur almost exclusively in the L-configuration. Protein amino acids synthesized by non-biological processes in the laboratory have resulted exclusively in racemic mixtures. Unfortunately, most amino acids that have been extracted from meteorites are partially racemic, thus complicating an assessment of their modes of origin. Alternative pathways for the occurrence of partially racemized amino acids in biotic and abiotic materials are discussed in an attempt to clarify the significance of their occurrence in meteorites, in particular with respect to the origin of life in the solar system.
On the search for the amino acids on the lunar surface as it relates to other extraterrestrial bodies
Vera M. Kolb, Richard B. Hoover, Stephen A. Macko
The early search for the amino acids in the lunar surface fines indicated such a low amount of the amino acids that it was deemed insignificant, and possibly contamination. Although later studies departed in some ways from the earlier results, they were not pursued. In this paper we critically evaluate the results from the Apollo missions from the new perspective with considerations of the sensitivity of the instrumentation available at the time. We suggest that the relative abundances of amino acids seen in lunar soils are appreciably distinct from terrestrial signatures and are not the result of contamination. We discuss the possible relevance of the lunar results to the findings of the amino acids on the surfaces of other extraterrestrial bodies, such as Mars, as well as a need for further analytical approaches.
Fossil microorganisms and formation of Early Precambrian weathering crusts
M. M. Astafieva, A. Yu. Rozanov, A. B. Vrevsky, et al.
Weathering crusts are the only reliable evidences of continental conditions existence, and often are the only source of information about exogenous processes and subsequently about conditions under which the development of biosphere occurred. Complex of diverse fossil microorganisms was discovered in result of electronic-microscope investigations. Chemical composition of discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, microorganisms fixed in rocks played role of catalyst. Decomposition of minerals, comprising rocks, and their transformation into clayey (argillaceous) minerals, occurred most likely under influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.
Instrumentation for Astrobiology
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A spectroscopic polarimeter for detecting chiral signatures in astrobiological samples
We have developed a polarimeter for accurately measuring both the circular and linear polarization components of a light beam from 400 nm to 800 nm. This polarimeter is designed to work at low light levels that are typical in astronomical applications. It is optimized to detect the circular polarization signal that is orders of magnitude weaker than the linear polarization signal. Two photoelastic modulators (PEMs) are the key polarization components employed in this polarimeter to afford the high sensitivity required for the application. Using this instrument, we have quantified the circular polarization signal produced by astrobiologically relevant microorganisms and compared the results to macroscopic vegetation (such as leaves) and abiotic minerals. Our aim is to understand whether circular polarization offers a viable technique for remote detection of chiral signatures and hence will be useful as an element of telescopic searches for life elsewhere in the Universe. We see unambiguous circular polarization from photosynthetic microbes. The circular polarization of reflected light is related to the circular dichroism of photosynthetic molecules. Therefore, circular polarization spectroscopy offers the prospect of remotely sensing life's unique chiral signature.
Laser induced fluorescence emission (L.I.F.E.): in situ and remote detection of life in Antarctic and Alaskan ice
Once thought to be a barren desert devoid of life, it now appears that Earth's cryosphere is an ice ecosystem harbouring a rich community of metabolically active microorganisms inhabiting ice, snow, water, and lithic environments. The ability to rapidly survey this ecosystem during in situ and orbital missions is of considerable interest for monitoring Earth's carbon budget and for efficiently searching for life on Mars or any exoplanet with an analogous cryosphere. Laser induced fluorescence emission (L.I.F.E.) imaging and spectroscopy using excitation in ultraviolet (UV) wavelengths have been proposed as non-destructive astrobiological survey tools to search for amino acids, nucleic acids, microbial life, and polycyclic aromatic hydrocarbons (PAHs) deep in the Mars regolith. However, the technique is easily adapted to search for larger, more complex biomolecular targets using longer wavelength sources. Of particular interest is the ability for excitation at blue, green, and red wavelengths to produce visible and near infrared fluorescence of photosynthetic pigments in cyanobacteria-dominated microbial communities populating the ice of alpine, Arctic, and Antarctic lakes, glaciers, ice sheets, and even the supercooled water-ice droplets of clouds. During the Tawani 2008 International Antarctic Expedition we tested the in situ use of the technique as part of a field campaign in the Dry Valleys of Schirmacher Oasis and Lake Untersee, Queen Maud Land, Antarctica. In the spring of 2009, we performed airborne remote sensing tests of the technology in Alaska. In this paper we review our in situ laser detection experiments and present for the first time preliminary results on our efforts to detect cryosphere L.I.F.E. from an airborne platform.
Integrated ray tracing simulation of spectral bio-signatures from full 3D earth model
Dongok Ryu, Sehyun Seong, Jae-Min Lee, et al.
Accurate identification and understanding of spectral bio-signatures from possible extra terrestrial planets have received an ever increasing attention from both astronomy and space science communities in recent years. In pursuance of this subject, one of the most important scientific breakthroughs would be to obtain the detailed understanding on spectral biosignatures of the Earth, as it serves as a reference datum for accurate interpretation of collapsed (in temporal and spatial domains) information from the spectral measurement using TPF instruments. We report a new Integrated Ray Tracing (IRT) model capable of computing various spectral bio-signatures as they are observed from the Earth surface. The model includes the Sun, the full 3-D Earth, and an optical instrument, all combined into single ray tracing environment in real scale. In particular, the full 3-D Earth surface is constructed from high resolution coastal line data and defined with realistic reflectance and BSDF characteristics depending on wavelength, vegetation types and their distributions. We first examined the model validity by confirming the imaging and radiometric performance of the AmonRa visible channel camera, simulating the Earth observation from the L1 halo orbit. We then computed disk averaged spectra, light curves and NDVI indexes, leading to the construction of the observed disk averaged spectra at the AmonRa instrument detector plane. The model, computational procedure and the simulation results are presented. The future plan for the detailed spectral signature simulation runs for various input conditions including seasonal vegetation changes and variable cloud covers is discussed.
A micro fluorescent activated cell sorter for astrobiology applications
A micro-scale Fluorescent Activated Cell Sorter (μFACS) for astrobiology applications is under development. This device is designed to have a footprint of 7 cm x 7 cm x 4 cm and allow live-dead counts and sorting of cells that have fluorescent characteristics from staining. The μFACS system takes advantage of microfludics to create a cell sorter that can fit in the palm of the hand. A micron-scale channel allows cells to pass by a blue diode which causes emission of marker-expressed cells which are detected by a filtered photodetector. A small microcontroller then counts cells and operates high speed valves to select which chamber the cell is collected in (a collection chamber or a waste chamber). Cells with the expressed characteristic will be collected in the collection chamber. This system has been built and is currently being tested. We are also designing a system with integrated MEMS-based pumps and valves for a small and compact unit to fly on small satellite-based biology experiments.
Mars, Venus, and Astrobiology I
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The discovery of liquid water on Mars and its implications for astrobiology
N. O. Rennó, M. Mehta, B. P. Block, et al.
Since liquid water is a key ingredient for life as we know it, NASA has adopted the theme "follow the water" as an strategy for exploring Mars. Recently, Renno et al.1,2 showed evidence that liquid saline-water exists in areas disturbed by the Phoenix Mars Lander. Moreover, they argued that the thermodynamics of freeze-thaw cycles leads to the formation of concentrated saline solutions (brines) with freezing temperatures much higher than current summer ground temperatures where ground ice exists near the surface and therefore liquid saline-water should be common on Mars. Here we summarize these ideas, present some new results, and discuss their implications for astrobiology. We propose a strategy for searching for liquid saline water on Mars and argue that NASA's theme for the exploration of Mars should be updated to "follow the liquid water."
Methane and life on Mars
Gilbert V. Levin, Patricia Ann Straat
Mumma et al. 1 have confirmed earlier detections of methane in the Martian atmosphere, finding it localized and correlated with atmospheric water vapor. They determined that, because of the short half-life of methane, a continual replenishment is required to account for its presence. They also conclude that the dynamics of methane on Mars require a methane sink in the soil. It is suggested here that both phenomenon could be accounted for by an ecology of methane-producing and methane-consuming microorganisms. Such ecologies exist on Earth, where, generally, anaerobic methanogens live at depth and aerobic methanotrophs live at or near the surface. On Mars, with its essentially anaerobic atmosphere, both types of microorganisms could co-exist at or near the surface. It is possible that the Viking Labeled Release (LR) experiment detected methanogens in addition to other microorganisms evolving carbon dioxide since the LR instrumentation would detect methane, carbon dioxide, or any other carbon gas derived from one of the LR substrates. A simple modification of the LR experiment that could resolve the life on Mars issue is discussed.
Oxidation of organic materials with perchlorates: relevance to the chemistry on the Martian surface
No organic materials have been found on the Martian surface, based on the results from the Viking and Phoenix missions. The Phoenix mission detected the inorganic perchlorates in the Martian soil. Perchlorates are potent oxidizing substances. The high-temperature oxidative properties of perchlorates may promote combustion of organics in pyrolytic experiments. This may compromise the ability of Phoenix's TEGA (Thermal and Evolved Gas Analyzer) experiments to detect organics. The high temperature conditions of TEGA instrument are not representative of the environment on Mars. In this paper we pose a question if organic materials can survive oxidation with perchlorates at less drastic temperatures. We have surveyed the literature on oxidations of various groups of organic materials by perchlorates. Several amino acids, notably glycine and alanine, are quite resistant to this oxidation. The same is true for some heterocycles, purines and purimidines. These organic materials may have survived perchlorate oxidation in the natural environment on Mars.
Mars, Venus, and Astrobiology II
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Multi-fractal property of perchlorate reductase gene sequences and DNA photonics application to UV fluorescence detection on Mars-like surfaces
George Tremberger Jr., Eric Cheung, N. Gadura, et al.
The discovery of perchlorate on Mars raises the possibility of the existence of perchlorate reduction microbes on that planet. The perchlorate reductase gene sequence fractal dimensions of two Dechloromonas species were compared with five other sequences in the microbial dimethyl sulfoxide (DMSO) reductase family. A nucleotide sequence can be expressed as a numerical sequence where each nucleotide is assigned its proton number. The resulting numerical sequence can be investigated for its fractal dimension in terms of evolution and chemical properties for comparative studies. Analysis of the fractal dimensions for the DMSO reductase family supports phylogenetic analyses that show that the perchlorate reductase gene sequences are members of the same family. A sub-family with roughly the same nucleotide length emerges having the property that the gene fractal dimension is negatively correlated with the Shannon di-nucleotide entropy (R2 ~ 0.95, N =5). The gene sequence fractal dimension is found to be positively correlated with the neighbor joining distances reported in a published protein phylogeny tree (R2~ 0.92, N = 5). The multi-fractal property associated with these genes shows that perchlorate reductase has lower dimensionality as compared to the relatively higher dimensionality DNA-break repair genes Rec-A and Rad-A observed in the Dechloromonas aromatica and Deinococcus radiodurans genomes. The studied perchlorate gene sequences show a higher Shannon di-nucleotide entropy (~3.97 bits) relative to Dechloromonas aromatica DNA repair sequences (~3.87 bits Rec-A, ~3.92 bits Rad-A), suggesting that there are fewer constraints on nucleotide variety in the perchorlate sequences . These observations thus allow for the existence of perchlorate reducing microbes on Mars now or in the past. Timeresolved UV fluorescence study near the emission bands of nucleotide sequences could be used for bio-detection on Mars-like surfaces and the results may further constrain the proposed conjectures.
Can Venus shed microorganisms?
The pale featureless cloud tops of Venus reveal a rich complexity when viewed in ultraviolet. These features result from an unknown absorber brought up from lower atmospheric levels by convection, particularly at lower latitudes. While the surface of Venus is extremely hostile to life as we know it, there exists a habitable region in the atmosphere, centered at approximately 50 km, where the temperature ranges from 30 to 80ºC and the pressure is one bar. Numerous examples of cloud-borne life exist on Earth. However, the environment in the Venus atmospheric habitable zone has only a few ppm of water which is present as misty droplets, strong sulfuric acid, and intense UV illumination. The proposal that putative cloud-borne life forms in Venus' atmospheric habitable zone can be transported to Earth by a solar conveyance face several challenges. Vigorous convective mixing, especially at the lower latitudes is considered as a means of transport to the upper reaches of Venus' atmosphere. Potential propulsive forces imparted by both solar wind and sunlight pressure are considered as a means of achieving escape velocity from Venus. Additional hurdles include direct exposure by such transported life forms to the rigors of the space environment. These are contrasted to those experienced by microorganisms that may be carried within meteorites and comets. A middle ground is perhaps demonstrated by plankton that has been observed at high altitudes on Earth, likely lofted there by a hurricane, which is encased in protective ice crystals.
Raman imaging for high throughput biomarker field detections
Zuki Tanaka, Thomas Beer, Christopher P. McKay, et al.
We explore the feasibility of using Raman imaging as a technique for identifying areas of high astrobiological interest on Mars-like surfaces. This paper will discuss the technique, analysis, and possible deployment of rover mounted instrumentation for identifying biogenic samples from Mars analog environments, such as the Mojave Desert and Lassen Volcanic National Park. We also discuss using this technique for the non-destructive, in situ identification snow algae found in harsh environments.
Microbial Extremophiles I
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Diversity of bacterial communities in the lakes of Schirmacher Oasis, Antarctica
Nazia Mojib, Jonathan Huang, Richard B. Hoover, et al.
Extreme conditions such as low temperature, aridness, low availability of organic matter, high salinity and UV-radiation in terrestrial Antarctica are key factors limiting the habitation of biotic communities and ecosystem dynamics. In recent studies, it has been discovered that the bacterial communities are highly diverse and distributed widely in the extreme ecosystem of Antarctica. Besides available morphometric data, geology, and thermal profile, limited study on the microbial identification, phylogenetic analysis, diversity and distribution of microorganisms in different lakes of Schirmacher Oasis in East Antarctica has been reported. The objective of this study was to assess the microbial biodiversity and distribution using culture-independent and culture-dependent methodologies based upon bacterial 16S rRNA gene analysis in three categories of lakes, i.e., the land-locked (L), epi-shelf (E), and pro-glacial (P) lakes in Schirmacher Oasis. The water and ice samples were collected during the 2008 Tawani International Scientific Expedition. Direct culturing of the samples on R2A agar media exhibited a wide variety of pigmented bacteria. Two of the pigmented bacteria that were cultured belong to the genera, Hymenobacter, and Flavobacterium. Cultureindependent methodology of one of the land-locked lakes L27C identified a rich microbial diversity consisting of six different phyla of bacteria. The majority of bacteria (56%) belong to the Class γ-proteobacteria within the phylum Proteobacteria. Within the Class γ-proteobacteria, Acinetobacter dominated (48%) the total microbial load. Characterization of the microbial diversity within the three different types of Antarctic lakes is important because it will help give us a better understanding of the survival mechanisms and the functionality of these bacteria in extremely cold and harsh Antarctic ecosystems.
Anaerobic psychrophiles from Lake Zub and Lake Untersee, Antarctica
The study of samples from Antarctica 2008 and 2009 expeditions organized and successfully conducted by Richard Hoover led to the isolation of diverse anaerobic strains with psychrotolerant and psychrophilic physiology. Due to the fact that Lake Untersee has never been subject to microbiological study, this work with the samples has significant and pioneering impact to the knowledge about the biology of this unique ecosystem. Also, the astrobiological significance for the study of these ecosystems is based on new findings of ice covered water systems on other bodies of our solar system. Anaerobic psychrotolerant strain LZ-22 was isolated from a frozen sample of green moss with soils around the rhizosphere collected near Lake Zub in Antarctica. Morphology of strain LZ-22 was observed to be motile, rod shaped and spore-forming cells with sizes 1 x 5-10 μm. This new isolate is a mesophile with the maximum temperature of growth at 40°C. Strain LZ-22 is able to live on media without NaCl and in media with up to 7 % (w/v) NaCl. It is catalase negative and grows only on sugars with the best growth rate being on lactose. The strain is a neutrophile and grows between pH 5 and 9.0 with the optimum at 7.8. Another two strains UL7-96mG and LU-96m7P were isolated from deep water samples of Lake Untersee. Proteolytic strain LU-96m7P had a truly psychrophilic nature and refused to grow at room temperature. Sugarlytic strain UL7-96mG was found to be psychrotolerant, but its rate of growth at 3°C was very high compared with other mesophiles. Two homoacetogenic psychrophilic strains A7AC-96m and AC-DS7 were isolated and purified from samples of Lake Untersee; both of them are able to grow chemolithotrophically on H2+CO2. In the presence of lactate, these strains are able to grow only at 0-18 °C, and growth at 22 °C was observed only with yeast extract stimulation. In this paper, physiological and morphological characteristics of novel psychrophilic and psychrotolerant isolates from Antarctica 2008 and 2009 expeditions will be discussed.
Psychrotolerant anaerobes from Lake Podprudnoye, Antarctica and penguin Spheniscus demersus colony, South Africa
The study of a sample collected from a wind-made ice sculpture near Lake Podprudnoe, Antarctica led to the isolation of the psychrotolerant strain ISLP-3. Cells of the new isolate are vibrio-shaped that measure 0.5 x 1.0-3.0 μm in size. Growth occurs within the temperature range 5-35ºC with the optimum at 22 °C. Salinity range for growth is 0-2 % NaCl with the optimum at 0.25 %. The new isolate grows within a pH range from 6.0 to 9.5 with the optimum at 7.5. Strain ISLP-3 is saccharolytic, growing on the following substrates: D-glucose, D-ribose, D-fructose, D-arabinose, maltose, sucrose, D-trehalose, D-mannose, D-cellobiose, lactose, starch, chitin, triethylamine, N-acetylglucosamine, and urea. The best growth occurred on D-cellobiose. An environmental sample of pond water near a colony of the endemic species of African penguins, Spheniscus demersus, was collected in February 2008 and delivered directly to the Astrobiology laboratory at NSSTC. The microbiological study of this sample led to the isolation of two psychrotolerant strains ARHSd-7G and ARHSd-9G. Both strains are strictly anaerobic bacteria and are able to grow at high pH and low temperatures. The cells of strain ARHSd-7G are motile, vibrio-shaped, spore-forming cells. Optimal growth of this strain occurs at 30 ºC, 3 % NaCl, and pH 8.9. The isolate ARHSd-7G combines sugarlytic and proteolytic metabolisms, growing on some proteolysis products including peptone and yeast extract and a number of sugars. The second isolate, ARHSd-9G, exhibits thin, elongated rods that measure 0.4 x 3-5 μm. The cells are motile and spore-forming. Optimal growth of strain ARHSd-9G occurs at 30 ºC, 1.75 % NaCl, and pH 8.5. The strain ARHSd-9G is sugarlytic, growing well on substrates such as D-glucose, sucrose, D-cellobiose, maltose, fructose, D-mannose, and trehalose (the only exception is positive growth on yeast extract). In this report, the physiological and morphological characteristics of the novel psychrotolerant, alkaliphilic, and neutrophilic isolates from the Antarctica 2008 expedition will be discussed.
Cryoprotection from bacterial teichoic acid
Charles V. Rice, William Harrison, Karl Kirkpatrick, et al.
Recent studies from our lab demonstrated that teichoic acid is surrounded by liquid water at -40 °C. The size and shape of the liquid water pockets has been visualized with fluorescence microscopy images of aqueous Rhodamine- B solutions. The long, thin channels surround ice crystals with a size of 5-20 microns. Subsequent studies show that B. subtilis Gram-positive bacteria are sequestered into large pockets without added teichoic acid. Here, the ice crystals are orders of manitude larger. When bacteria are mixed with teichoic acid solutions, the distribution of bacteria changes dramatically. The smaller ice crystals allow the bacteria to align in the thin channels of liquid water seen with teichoic acid only. The role of teichoic acid in the freeze tolerance was examined with live/dead fluorescence assays of bacteria mixed with teichoic acid. These quantitative assays were used to determine if teichoic acid acts in a synergetic fashion to enhance the survivability of E. coli, a gram-negative species which lacks teichoic acid. Additionally, we have obtained B. subtilis mutants lacking wall-associated teichoic acids to evaluate cryoprotection compared to the wild-type strain.
An optical spectroscopic study correlating the yellow rain and cultured red rain microbes
A. Santhosh Kumar, Godfrey Louis
A number of cases of yellow colored rain occurred in Kerala, India in July-August 2001 along with the red rain phenomenon. Recently during the end of July 2008 a few cases of yellow colored rain again occurred in Kerala and during the same time, unusual rain, termed as "blood rain" occurred in Bagado, Colombia. In this paper we show that the yellow rain and red rain can have a common origin. The yellow rainwater also exhibits the same unusual autofluorescence reported earlier for the cultured red rain microbes. Reasons for considering extraterrestrial origin for these colored rains are discussed.
Microbial Extremophiles II
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Life in ice: implications to astrobiology
During previous research expeditions to Siberia, Alaska and Antarctica, it was observed that glaciers and ice wedges contained bacterial cells that became motile as soon as the ice melted. This phenomenon of live bacteria in ice was first documented for microbes in ancient ice cores from Vostok, Antarctica. The first validly published species of Pleistocene bacteria alive on Earth today was Carnobacterium pleistocenium. This extremophile had remained for 32,000 years, encased in ice recently exposed in the Fox Tunnel of Alaska. These frozen bacteria began to swim as soon as the ice was thawed. Dark field microscopy studies revealed that large numbers of bacteria exhibited motility as soon as glacial ice was melted during our recent Expeditions to Alaska and Antarctica led to the conclusion that microbial life in ice was not a rare phenomenon. The ability of bacteria to remain alive while frozen in ice for long periods of time is of great significance to Astrobiology. In this paper, we describe the recent observations and advance the hypothesis that life in ice provides valuable clues to how we can more easily search for evidence of life on the Polar Caps of Mars, comets and other icy bodies of our Solar System. It is suggested that cryopanspermia may have played a far more important role in Origin of Life on Earth and the distribution of Life throughout the Cosmos and than previously thought possible.
Nucleotide fluctuation of radiation-resistant Halobacterium sp. NRC-1 single-stranded DNA-binding protein (RPA) genes
Todd Holden, G. Tremberger Jr., E. Cheung, et al.
The Single-Stranded DNA-Binding Protein (RPA) Genes in gamma ray radiation-resistant halophilic archaeon Halobacterium sp. NRC-1 were analyzed in terms of their nucleotide fluctuations. In an ATCG sequence, each base was assigned a number equal to its atomic number. The resulting numerical sequence was the basis of the statistical analysis in this study. Fractal analysis using the Higuchi method gave fractal dimensions of 2.04 and 2.06 for the gene sequences VNG2160 and VNG2162, respectively. The 16S rRNA sequence has a fractal dimension of 1.99. The di-nucleotide Shannon entropy values were found to be negatively correlated with the observed fractal dimensions (R2~ 0.992, N=3). Inclusion of Deinococcus radiodurans Rad-A in the regression analysis decreases the R2 slightly to 0.98 (N=4). A third VNG2163 RPA gene of unknown function but with upregulation activity under irradiation was found to have a fractal dimension of 2.05 and a Shannon entropy of 3.77 bits. The above results are similar to those found in bacterial Deinococcus radiodurans and suggest that their high radiation resistance property would have favored selection of CG di-nucleotide pairs. The two transcription factors TbpD (VNG7114) and TfbA (VNG 2184) were also studied. Using VNG7114, VNG2184, and VNG2163; the regression analysis of fractal dimension versus Shannon entropy shows that R2 ~ 0.997 for N =3. The VNG2163 unknown function may be related to the pathways with transcriptions closely regulated to sequences VNG7114 and VNG2184.
Astrobiology and Planetary Protection
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Origin of petroleum within our solar system, a review: emphasis on the future prospects of major oil and gas discovery within Mars and moons of various planets
Prasanta K. Mukhopadhyay, David J. Mossman, James M. Ehrman
Results of earlier research using organic petrological, geochemical, SEM-EDX, and FSSEM confirm the presence of abundant biogenic components in terrestrial sedimentary rocks since 3.5 Ga. These organic components in the Precambrian terrestrial sediments and within the carbonaceous chondrites (CCs) possibly originated from organisms such as archaea and prokaryotes. Our ongoing results on selected CCs indicate that these biopolymers and geopolymers are the main sources of all recent hydrocarbons (oil and gas) within our Solar System (especially within Mars, various moons of the Saturn, and Comets) similar to early terrestrial environment. These hydrocarbons are possibly derived from three temperature-influenced transformations of organic remains: (a) Low-temperature induced (50-200°C): Hydrocarbons (oil and gas) are derived from the bacterial and other primitive organic remains (e.g. Murchison, Orgueil, and Tagish Lake); (b) Transitional-temperature induced (200-300°C): These hydrocarbons are formed directly from the biopolymers either within deeper part of the individual planet or asteroids using a mineral catalyst or from a direct transformation on the surface of the individual Planet or Asteroid bodies by intense solar radiation (e.g. ALH 840001 and NWA), and (c) High temperature and pressure induced (350-500°C) - These hydrocarbons (pyrobitumen, inert kerogen, and mainly methane) are formed in a superheated (hydrothermal) environment similar to that of the biological habitat within hydrothermal vents along terrestrial midoceanic ridges (e.g. Allende, EET and Vigarano). In such an extreme oxygen-depleted environment, biological life and hydrocarbon generation are intimately linked. Apart from the concept of panspermia, our earlier data highlights a possible link between universal life, biopolymers, geopolymers and their thermal decomposition to hydrocarbons (oil and gas) in various planets similar to terrestrial sediments. The organics and water within CCs and comets, recent discoveries of methane, gas hydrates, water as ice and snow storms, and the key geological features within Mars, liquid low molecular weight hydrocarbon (methane to propane) lakes and solid gas hydrates within various moons of Saturn and Jupiter all point to the presence of biologically derived petroleum within our Solar System. Our model of a Universal Unconventional Petroleum System promises major prospects of oil and gas throughout our Solar System and especially within Mars and various moons of Saturn. Based on the physicochemical constraints, earlier research, and recent discoveries we predict a major prospect of heavy oil (similar to Tar Sand in Alberta, Canada) and light hydrocarbon gases within Mars.
Panspermia and horizontal gene transfer
Evidence that extremophiles are hardy and ubiquitous is helping to make panspermia a respectable theory. But even if life on Earth originally came from space, biologists assume that the subsequent evolution of life is still governed by the darwinian paradigm. In this review we show how panspermia could amend darwinism and point to a cosmic source for, not only extremophiles but, all of life. This version of panspermia can be called "strong panspermia." To support this theory we will discuss recent evidence pertaining to horizontal gene transfer, viruses, genes apparently older than the Earthly evolution of the features they encode, and primate-specific genes without identifiable precursors.
On the applicability of the identity problem to astrobiology
We show that the philosophical problem of identity carries over to the definition of life. The identity problem presents a major obstacle for creation of a straightforward definition of life. We superimpose the identity problem to the problem we have previously examined, that of the life forms. We conclude that any definition of life must consider simultaneously these two problems. The definition of life, which we consider, is that life of an individual organism is a sum of its successive life forms, each unique in time and space. The identity of each of the life forms of an individual organism needs to be connected to the identity of the organism. The astrobiological relevance of the identity problem is illustrated on various examples.
Astrobiology and green chemistry: a new pedagogical connection
Various pedagogical approaches are needed to introduce astrobiology into the chemistry curriculum. We are developing a new approach in which we connect green chemistry with astrobiology. Green chemistry is chemistry which is environmentally friendly. One obvious way for the organic chemistry to be environmentally friendly is to use water as solvent, instead of more toxic organic solvents. Another approach is to run so-called solventless reactions. For example, as the solid materials are mixed together, the melting point of the mixture is lower than the melting points of its individual components (the principle of the mixed-melting point). In some cases the entire mixture may melt upon mixing. The reactions would then occur in a viscous semi-solid state. An additional approach is to run the reactions by utilizing enzymes or man-made protein mimics as catalysts instead of toxic catalysts, such as those based on the transition metals. These and some other known examples of green chemistry have a great potential for astrobiology. The astrobiological reactions typically occur in water (e.g. prebiotic soup), in the solid mixtures (e.g. on the meteors), and may be catalyzed by various short peptides. The connection between the green chemistry principles and astrobiology represents a new pedagogical approach for infusion of astrobiology into the organic chemistry.
The Drake Equation revisited
In the almost half century since the Drake Equation was first conceived, a number of profound discoveries have been made that require each of the seven variables of this equation to be reconsidered. The discovery of hydrothermal vents on the ocean floor, for example, as well as the ever-increasing extreme conditions in which life is found on Earth, suggest a much wider range of possible extraterrestrial habitats. The growing consensus that life originated very early in Earth's history also supports this suggestion. The discovery of exoplanets with a wide range of host star types, and attendant habitable zones, suggests that life may be possible in planetary systems with stars quite unlike our Sun. Stellar evolution also plays an important part in that habitable zones are mobile. The increasing brightness of our Sun over the next few billion years, will place the Earth well outside the present habitable zone, but will then encompass Mars, giving rise to the notion that some Drake Equation variables, such as the fraction of planets on which life emerges, may have multiple values.
X-Ray, UV, Visible, and IR Instrumentation for Planetary Missions
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Planetary science experiments flying as hosted payloads on commercial satellites
Eliot F. Young, Cathy B. Olkin, Phillip M. Kalmanson, et al.
There has been a recent surge in interest in hosted and rideshare payloads that would launch aboard commercial communications satellites. Much of this interest originates with the satellite customers themselves as a way to sell excess mass and power margins that exist at launch. In 2008, NASA selected GOLD (Global-scale Observations of the Limb and Disk) as a mission of opportunity to fly as its first hosted payload experiment on a geosynchronous commercial communications satellite, a STAR-2 bus satellite built by Orbital Sciences. CHIRP (Commercially Hosted Infrared Payload), a hosted payload to test infrared sensors for the Air Force, is also being developed for a STAR-2 bus communications satellite. The mass limitation on a STAR-2 bus hosted payload is roughly 50 - 60 kg and the volume is roughly constrained to a 25" x 30" x 28" box on the nadir deck. Telescope apertures are therefore limited is size to about 50 cm in diameter. The diffraction limit for visible (much less IR) imaging missions barely improves upon ground-based image performance, but UV missions can achieve better than 0.1" resolution. There is at least one family of optical designs that (a) provide the necessary focal length and (b) are light and compact enough to fit within the STAR-2 bus mass and volume constraints. These designs also afford opportunities to maintain 0.05" pointing accuracy through a combination of a fine steering mirror and an orthogonal transfer CCD.
In-flight performance of the Long Range Reconnaissance Imager (LORRI) on the New Horizons Mission
M. W. Noble, S. J. Conard, H. A. Weaver, et al.
The LOng-Range Reconnaissance Imager (LORRI) is a high resolution imaging instrument on the New Horizons spacecraft. New Horizons will collect data during a fly-by of Pluto and its satellites in 2015, and may continue on to collect data at another Kuiper Belt Object in an extended mission phase. New Horizons launched on January 19, 2006, the first mission of NASA's New Frontiers program. LORRI is a narrow field of view (0.29°), Ritchey-Chrétien telescope with a 20.8 cm diameter primary mirror. The telescope has an effective focal length of 262 cm and has a three lens field flattener near the focal plane. The focal plane unit consists of a 1024 × 1024 pixel charge-coupled device detector operating in frame transfer mode. LORRI provides panchromatic imaging over a bandpass that extends approximately from 350 nm to 850 nm. The instrument operates in an extreme thermal environment, viewing space from within the warm spacecraft. For this reason, LORRI has a silicon carbide optical system with passive thermal control, designed to maintain focus without adjustment over a wide temperature range from -100 C to +50 C. LORRI has been successfully operated through initial commissioning, a fly-by of Jupiter, and two annual checkout periods. We describe the in-flight testing and measured performance of LORRI, and provide comparisons to pre-launch performance predictions. We also detail plans under consideration for changing LORRI's flight software to accommodate autonomous detection of targets within the instrument's field of view.
In-flight performance of MESSENGER's Mercury Dual Imaging System
S. Edward Hawkins III, Scott L. Murchie, Kris J. Becker, et al.
The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, launched in August 2004 and planned for insertion into orbit around Mercury in 2011, has already completed two flybys of the innermost planet. The Mercury Dual Imaging System (MDIS) acquired nearly 2500 images from the first two flybys and viewed portions of Mercury's surface not viewed by Mariner 10 in 1974-1975. Mercury's proximity to the Sun and its slow rotation present challenges to the thermal design for a camera on an orbital mission around Mercury. In addition, strict limitations on spacecraft pointing and the highly elliptical orbit create challenges in attaining coverage at desired geometries and relatively uniform spatial resolution. The instrument designed to meet these challenges consists of dual imagers, a monochrome narrow-angle camera (NAC) with a 1.5° field of view (FOV) and a multispectral wide-angle camera (WAC) with a 10.5° FOV, co-aligned on a pivoting platform. The focal-plane electronics of each camera are identical and use a 1024×1024 charge-coupled device detector. The cameras are passively cooled but use diode heat pipes and phase-change-material thermal reservoirs to maintain the thermal configuration during the hot portions of the orbit. Here we present an overview of the instrument design and how the design meets its technical challenges. We also review results from the first two flybys, discuss the quality of MDIS data from the initial periods of data acquisition and how that compares with requirements, and summarize how in-flight tests are being used to improve the quality of the instrument calibration.
Radiometric performance results of the Lunar Reconnaissance Orbiter's Lyman Alpha Mapping Project (LRO/LAMP) UV imaging spectrograph
Michael W. Davis, David C. Slater, G. Randall Gladstone, et al.
We describe the pre-flight radiometric performance and calibration results of the Lunar Reconnaissance Orbiter's Lyman Alpha Mapping Project (LRO/LAMP) flight model. LAMP is a lightweight (6.1 kg), low-power (4.5 W), ultraviolet spectrograph based on the ALICE instruments now in flight aboard the European Space Agency's Rosetta spacecraft and NASA's New Horizons spacecraft. Its primary job will be to identify and localize exposed water frost in permanently shadowed regions (PSRs), and to characterize landforms and albedos in PSRs. Detailed radiometric performance results of the LAMP flight model are presented and discussed.
SwRI's Alice line of ultraviolet spectrographs
Kurt D. Retherford, S. Alan Stern, David C. Slater, et al.
Southwest Research Institute's (SwRI's) "ALICE" line of ultraviolet spectrographs (UVS) is founded on a lightweight, low power, and highly versatile instrument design. Generally small changes in detector photocathode, pixel size, slit shape, optical coatings, pinhole aperture implementations, and other minor tweaks have enabled a wide variety of applications for the ALICE design, including investigations of comets (Rosetta-ALICE), Pluto (New Horizons-ALICE), the Moon (Lunar Reconnaissance Orbiter (LRO)-Lyman Alpha Mapping Project (LAMP)), and Jupiter (Juno-UVS). ALICE's high capability and our experience with high radiation environment and outer solar system requirements make this UVS a good choice for future planetary mission concepts.
CRISM scan system
Kim Strohbehn, Teck Choo, John Hayes, et al.
The Compact Reconnaissance Imaging Spectrometer for Mars, (CRISM) is a visible-infrared imaging spectrometer that has been operating aboard the Mars Reconnaissance Orbiter (MRO) since November 2006. To achieve high spatial and spectral resolution CRISM's optical sensor unit (OSU) is gimbaled so that apparent along track motion can be removed by the scan system. Our paper describes the data processing flow, the physical scan control system and the performance achieved so far in orbit around Mars.
Moon4You: a combined Raman/LIBS instrument for lunar exploration
Erik C. Laan, Berit Ahlers, Wim van Westrenen, et al.
Moon4You is a project led by the Dutch Organisation for Applied Scientific Research TNO, with partners from industry and universities in the Netherlands that aims to provide a combined Raman / LIBS instrument as scientific payload for lunar exploration missions. It is the first time that Raman spectroscopy and LIBS (Laser Induced Breakdown Spectroscopy) are combined into one miniaturised instrument with minimum mass, volume and use of resources and can deliver data-products almost instantly. These characteristics make it the next-generation instrument for mineralogical and elemental (atomic) characterisation of lunar soil and rock samples, as well as for a host of other planetary exploration and terrestrial applications.
The Mercury Imaging X-ray Spectrometer: instrument overview
A. Martindale, J. F. Pearson, C. Whitford, et al.
We report progress in the design of the BepiColombo Mercury Imaging X-ray Spectrometer (MIXS). This instrument consists of two modules; a Wolter I soft X-ray telescope based on radially packed microchannel plate optics (MIXS-T) and a profiled collimator which uses a square pore square packed microchannel plate array to restrict its field of view (MIXS-C). Both instrument modules have identical focal planes (DEPFET macropixel array) providing an energy resolution of better than 200 eV FWHM throughout the mission. The primary science goal of MIXS is to perform X-ray fluorescence spectroscopy of the Hermean surface with unprecedented spatial and energy resolution. This allows discrimination between different regolith types, and by combining with data from other instruments, between competing models of crustal evolution and planetary formation. MIXS will also probe the complex coupling between the planet's surface, exosphere and magnetosphere by observing Particle Induced X-ray Emission (PIXE).
DEPFET-based instrumentation for the MIXS focal plane on BepiColombo
J. Treis, L. Andricek, F. Aschauer, et al.
BepiColombo, ESA's fifth cornerstone mission, is a planetary exploration mission to Mercury. On board of BepiColombo's Mercury Planetary Orbiter (MPO), the MIXS instrument will perform a complete X-ray fluorescence analysis of Mercury's crust with unprecedented spectral and spatial resolution. This is achieved by using a lightweight X-ray mirror system and by using of DEPFET based Macropixel devices as X-ray detectors. DEPFET based Macropixel detectors combine the advantages of the DEPFETs, like flexible readout modes, Fano-limited energy resolution and low power consumption, with the properties of the drift detectors, like arbitrary scalable pixel size and geometry. In addition, the excellent properties of the entrance window, like good QE even in the low energy range and 100% fill factor, are preserved. An energy resolution better than 200 eV FWHM @ 1 keV and an energy range from 0.5 keV to 10 keV, for a pixel size of 300 x 300 square micron, is required. To be sensitive to the Iron-L energy, the quantum efficiency at 0.5 keV is required to be larger than 80%. Main challenges for the instrument are the difficult radiation and thermal environment in the mercury orbit. The production of the first batch of flight devices has been finished at the MPI semiconductor laboratory, and first laboratory modules have been built. The properties of the sensors have been evaluated at the BESSY facility, and the devices have been used for XRF measurements at the ELETTRA synchrotron facility in Trieste. The results of the first tests will be presented here.
Poster Session
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The Mercury Imaging X-ray Spectrometer: optics design and characterisation
A. Martindale, J. F. Pearson, G. W. Fraser, et al.
We report progress in the design, theoretical modeling and experimental characterisation of microchannel plate (MCP) X-ray optics for the BepiColombo Mercury Imaging X-ray Spectrometer (MIXS). We show that MCP optics technology allows the design of a highly capable imaging telescope with 1 m focal length, a 1° field of view and approximately 50 cm2 of on-axis effective area at 1 keV. Of a total instrument mass budget 7.3 kg, less than 2.3 kg is allocated to the optics assemblies, telescope tubes, support structures and the electron diverters (used to deflect electrons from the focal plane). The instrument science goals require an imaging resolution of 9 arcminutes, with a design goal of 2 arcminutes. Recent experimental data, taken from individual optic elements is presented to show that MCP quality is in good agreement with the error budgets assumed in theoretical calculations of performance.
Development of a silicon drift detector array: an x-ray fluorescence spectrometer for remote surface mapping
Over the past three years NASA Marshall Space Flight Center has been collaborating with Brookhaven National Laboratory to develop a modular Silicon Drift Detector (SDD) X-Ray Spectrometer (XRS) intended for fine surface mapping of the light elements of the moon. The value of fluorescence spectrometry for surface element mapping is underlined by the fact that the technique has recently been employed by three lunar orbiter missions; Kaguya, Chandrayaan-1, and Chang'e. The SDD-XRS instrument we have been developing can operate at a low energy threshold (i.e. is capable of detecting Carbon), comparable energy resolution to Kaguya (<150 eV at 5.9 keV) and an order of magnitude lower power requirement, making much higher sensitivities possible. Furthermore, the intrinsic radiation resistance of the SDD makes it useful even in radiation-harsh environments such as that of Jupiter and its surrounding moons.
Section
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Front Matter: Volume 7441A
This PDF file contains the front matter associated with SPIE Proceedings Volume 7441A, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.