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Project Reports

• Advancing Methods for the Analyses of Organic Molecules in Sediments

  Eigenbrode’s research focuses on understanding the formation and preservation of organic and isotopic sedimentary records of ancient Earth and Mars. To this end, and as part of GCA’s Theme IV effort, Eigenbrode seeks to overcome sampling and analytical challenges associated with organic analyses of samples relevant to astrobiology. She modifies and develops methods of contamination tracking, sampling, and analysis (primarily gas chromatography mass spectrometry, GCMS) that improve the recovery of meaningful observations and provide protocol guidance for future astrobiological missions.

  ROADMAP OBJECTIVES: 2.1 2.2 7.1

• Investigation 1: Habitability of Icy Worlds

  Habitability of Icy Worlds investigates the habitability of liquid water environments in icy worlds, with a focus on what processes may give rise to life, what processes may sustain life, and what processes may deliver that life to the surface. Habitability of Icy Worlds investigation has three major objectives. Objective 1, Seafloor Processes, explores conditions that might be conducive to originating and supporting life in icy world interiors. Objective 2, Ocean Processes, investigates the formation of prebiotic cell membranes under simulated deep-ocean conditions, and Objective 3, Ice Shell Processes, investigates astrobiological aspects of ice shell evolution.

  ROADMAP OBJECTIVES: 2.1 2.2 3.2 4.1 5.1 5.2 5.3 6.2 7.1 7.2

• Cosmic Distribution of Chemical Complexity

  This project explores the connections between chemistry in space and the origin of life. It is comprised of three tightly interwoven tasks. We track the formation and evolution of chemical complexity in space starting with simple carbon-rich molecules such as formaldehyde and acetylene. We then move on to more complex species including amino acids, nucleic acids and polycyclic aromatic hydrocarbons. The work focuses on carbon-rich species that are interesting from a biogenic perspective and on understanding their possible roles in the origin of life on habitable worlds. We do this by measuring the spectra and chemistry of analog materials in the laboratory, by remote sensing with small spacecraft, and by analysis of extraterrestrial samples returned by spacecraft or that fall to Earth as meteorites. We then use these results to interpret astronomical observations made with ground-based and orbiting telescopes.

  ROADMAP OBJECTIVES: 2.1 2.2 3.1 3.2 3.4 4.3 7.1 7.2

• Life Underground

  Our multidisciplinary team from USC, Caltech, JPL, DRI, and RPI is developing and employing field, laboratory, and modeling approaches aimed at detecting and characterizing microbial life in the subsurface—the intraterrestrials. We posit that if life exists, or ever existed, on Mars or other planetary body in our solar system, evidence thereof would most likely be found in the subsurface. This study takes advantage of unique opportunities to explore the subsurface ecosystems on Earth through boreholes, mine shafts, and deeply-sourced springs. Access to the subsurface, both continental and marine, and broad characterization of the rocks, fluids, and microbial inhabitants is central to this study. Our focused research themes require subsurface samples for laboratory and in situ experiments. Specifically, we seek to carry out in situ life detection and characterization experiments, employ numerous novel and traditional techniques to culture heretofore unknown intraterrestrial archaea and bacteria, and incorporate new and existing data into regional and global metabolic energy models.

  ROADMAP OBJECTIVES: 2.1 2.2 3.1 3.3 4.1 5.1 5.2 5.3 6.1 6.2 7.2

• Task 1.1.1: Leaching of Radiogenic Potassium From Titan’s Core Into Its Ocean

  Working with graduate student Jason Hofgartner and NAI collaborator Christophe Sotin, we modeled the equilibrium chemistry of potassium at high pressure in the interior aqueous media in Saturn’s moon Titan to determine the extent of potassium leaching. This, in turn, allows us to test the hydrated silicate core model proposed by J. Castillo-Rogez and NAI Titan deputy PI Jonathan Lunine.

  ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.2 7.1

• Alteration of Asteroid Surfaces, Martian Meteorites and Terrestrial Rocks

  The inner solar system is relatively dry, but recent discoveries of water ice on the Moon, the subsurface of Mars, and potentially on a small class of asteroids known as main belt comets (MBCs), has forced us to re-evaluate our understanding of the inner solar system volatile distribution. Understanding the water content in asteroids and its evolution with time will be critical to constrain the origin and evolution of water in the asteroid belt.

  Interpreting the early aqueous history of the solar system requires an understanding of the processes that alter the original materials, including secondary alteration of minerals within parent bodies, and processes termed space weathering that influence surface layers. The nakhlite group of Martian meteorites is known to contain secondary alteration minerals that formed on Mars. We studied the fine-scale mineralogy and chemistry of these alteration minerals, and compared them to terrestrial alteration minerals formed in the Antarctic. The aim of these comparisons was to determine whether conditions such as water/rock ratio, pH and temperature were similar during the formation of alteration minerals in both planetary environments. Hence, the suitability of the Antarctic as a martian analogue site was tested.

  The distribution of MBCs and asteroids with hydrated minerals provide us with a tool to constrain the position of the snow line within the asteroid belt, which has important implications for the origin and distribution of volatiles for the terrestrial planets. However we need to understand the processes that alter the surface composition to be able to interpret the observations in the context of early solar system volatile distribution. Space weathering has been largely associated with “dry” S-type asteroids and is known to decrease the absorption depths and redden the spectral slopes of their surfaces. Only recently have studies indicated that C-type asteroids experience space weathering as well. Currently there are two contrasting views of how space weathering modifies the surfaces of these asteroids. One study found that the spectral slopes become redder with age, similar to S-type asteroids, but another study found that the spectral slopes become neutral with age. This discrepancy has been attributed to sampling effects and differences in mineralogy among C-type asteroids.

  ROADMAP OBJECTIVES: 1.1 2.1 3.1

• Project 1B: The Extraction of Spiked Amino Acids From a Set of (Clay-Rich) Minerals

  In the search for life on Earth and beyond, scientists scan for molecular organic compounds indicative for life, called biomarkers. Amino acids are among the most widespread biomolecules on Earth and play an important role in terrestrial biology by being, among other things, the building blocks of proteins. Thus, they are also selected as priority biomarkers for future life detection missions on Mars. Efficient extraction and detection of these biomarkers is of great importance. It is well known that amino acids degrade over time. This is caused by enzymatic and oxidative processes, as well as by UV- and ionizing radiation from the Sun, unless they are shielded from these influences. Mineral substrates, in particular clays such as montmorillonite, adsorb organic compounds efficiently and may have played a central role in the evolution of life. Rock formations, built up from clay-rich minerals, are therefore a priority target for life detection strategies. However, strong adsorption of amino acids by clay-rich minerals in turn inhibits extraction, resulting in low recovery rates. The aim of this study was to determine the extraction efficiency of amino acids from several distinctive (clay-rich) minerals. This was achieved by spiking minerals with amino acid solutions. After spiking, the samples were subjected to an extraction method. The abundances of recovered amino acids were then compared to the content of the original spiking solutions. Before the extraction experiments were conducted, several parameters were determined that could influence extraction rates (particle size, swelling capacities of the minerals, and carbon/nitrogen content). In this report we discuss preliminary results of adsorption properties of four amino acids: Arginine, Aspartic acid, Glutamic acid and Serine.

  ROADMAP OBJECTIVES: 2.1

• Advancing Techniques for in Situ Analysis of Complex Organics: Laser Mass Spectrometry of Planetary Materials

  This line of work within the Goddard Center for Astrobiology (GCA) seeks to connect key science objectives related to understanding organics in our solar system to specific techniques and protocols that may enable us to achieve those objectives with in situ investigations. In particular, laser mass spectrometry (MS) techniques are being developed for analysis of complex, nonvolatile organic molecules, such as those that might be found at Mars, Titan, comets, and other planetary bodies, with limited chemical sample manipulation, preparation, and processing (as may be required by flight missions). The GCA laser MS effort is complementary to both (i) instrument development work supported by NASA programs such as ASTID, PIDDP, and MatISSE, to forward the design and testing of new prototype spaceflight hardware, and (ii) ongoing research and development within Theme 4 of the GCA, concerning analytical chemical sample analysis as well as across GCA (particularly with Theme 3) to define combined analysis techniques that may affect future mission design. There are additionally aspects of this effort that relate to understanding synthetic pathways for certain complex organics in planetary environments. Areas of activity with GCA support during this period included: * Comparative study of prompt and two-step laser desorption MS (LDMS) analyses * Development of protocols for induced molecular dissociation and tandem mass spectrometry (MS/MS) * Mars analog analyses using laser TOF-MS, ion trap MS, and SAM-like protocols

  ROADMAP OBJECTIVES: 2.1 2.2 3.2 7.1

• Mineralogical Traces of Early Habitable Environments

  The goal of our work is to understand how habitability (potential to support life) varies across a range of physical and chemical parameters, in order to support a long term goal of characterizing habitability of environments on Mars.
  The project consists of two main components:
  1. We are examining the interplay between physicochemical environment and associated microbial communities in a subsurface environment dominated by serpentinization (a reaction involving water and crustal rocks, which indicated by surface mineralogy to have occurred on ancient Mars).
  2. We are working to understand how mineral assemblages can serve as a lasting record of prior environmental conditions, and therefore as indicators of prior habitability. This component directly supports the interpretation of mineralogy data obtained by the CheMin instrument on the Mars Science Laboratory.

  ROADMAP OBJECTIVES: 2.1 5.3

• Analysis of Prebiotic Organic Compounds in Astrobiologically Relevant Samples

  The Astrobiology Analytical Laboratory (AAL) of the GCA is dedicated to the study of organic compounds derived from past and future sample return missions, meteorites, lab simulations of Mars, interstellar, proto-planetary, and cometary ices and grains, and instrument development. This year, we analyzed the amino acid and nucleobase content of a martian meteorite; our findings suggested the presence of extraterrestrial amino acids in that meteorite. We studied irradiated benzene ices to determine that this type of radiation chemistry may have produced some of the complex aromatics found in meteorites. We identified amino acids for the first time in high-metal carbonaceous chondrite classes, supporting the idea of multiple formation mechanisms for these astrobiologically relevant compounds. We supported development of a liquid chromato-graphmass spectrometer aimed at in situ analyses of amino acids and chirality on airless bodies including asteroids and the outer planet’s icy moons Enceladus and Europa. We hosted a graduate student, an undergraduate, and a high-school intern, and participated in numerous public outreach and education events. We continued our participation in the OSIRIS-REx asteroid sample return mission and provided support for the Sample Analysis at Mars instrument of NASA’s Mars rover Curiosity.

  ROADMAP OBJECTIVES: 2.1 3.1

• Investigation 4: Path to the Flight

  The (Field Instrumentation and) Path to Flight investigation’s purpose is to enable in-situ measurements of organics and biological material with field instrumentation that have high potential for future flight instrumentation. The preceding three Investigations provide a variety of measurable goals used to modify or “tune” instrumentation that can be placed in the field. In addition the members of this Investigation provide new measurement capabilities that have been developed with the specific goal of life-detection. The instrument arsenal goes beyond the commercially available instrumentation and brings next generation imaging spectrometers, chromatographic, and sample extraction devices.

  ROADMAP OBJECTIVES: 2.1 2.2 6.1 7.1

• Astrobiology in Icy Extraterrestrial Environments

  Scientists in the Cosmic Ice Laboratory with the Goddard Center for Astrobiology (GCA) study the formation and stability of molecules under conditions found in outer space. In the past year, studies of amino-acid destruction were continued, a project on the formation of sulfate ions was completed (related to Europa), measurements of the infrared band strengths were published for application to the outer Solar System, and the formation and chemistry of a particularly-versatile interstellar molecule were investigated. All of this work is part of the Comic Ice Laboratory’s continuing contributions to understanding the chemistry of biologically-related molecules and chemical reactions in extra-terrestrial environments.

  ROADMAP OBJECTIVES: 2.1 2.2 3.1 7.1 7.2

• Project 1D: Potential for Microbial Iron Reduction in Chocolate Pots Hot Springs, Yellowstone National Park

  Iron biogeochemical cycling in circumneutral pH hot spring systems is an increasingly important astrobiological target, given recent discoveries on Mars by Curiosity. This study explored the potential for microbial reduction of ferric iron Fe(III) in the warm (ca. 40-60 C), circumneutral pH (ca. 6.0-6.5) Chocolate Pots (CP) hot springs in Yellowstone National Park. Endogenous microbial communities were able to reduce native CP Fe(III) oxides, as documented in most probable number (MPN) enumerations and ongoing enrichment culture studies. Microbial communities in the enrichments have been analyzed by high-throughput pyrosequencing of 16S rRNA gene amplicons. The sequencing revealed an abundance of the well-known Fe(III)-reducing bacterial species, Geobacter metallireducens, as well several other novel organisms with the potential to contribute to Fe(III) reduction. A shotgun metagenomic (paired-end Illumina sequencing) analysis of the enrichment cultures is in progress to explore the identity and function of G. metallireducens as well as other less well-characterized organisms in the cultures. Of particular interest are the likely presence of thermotolerance genes in the G. metallireducens metagenome, as well as outer membrane cytochrome genes that may be indicative of other Fe(III)-reducing organisms and provide evidence for pathways of electron flow in these cultures.

  ROADMAP OBJECTIVES: 2.1 5.1 6.1 7.1

• Biosignatures in Extraterrestrial Settings

  We are working on finding potentially habitable extrasolar planets, using a variety of search techniques, and developing some of the technology necessary to find and characterize low mass extrasolar planets. We also work on modeling and numerical techniques relevant to the problem of identifying extrasolar sites for life, and on some aspects of the prospects for life in the Solar System outside the Earth. The ultimate goal is to find signatures of life on nearby extrasolar planets.

  ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 4.1 4.3 6.2 7.1 7.2

• Project 5: Vistas of Early Mars: In Preparation for Sample Return

  To understand the history of life in the solar system requires knowledge of how hydrous minerals form on planetary surfaces, and the role minerals may play in the development of potential life forms. The minerals hematite and jarosite have been identified on Mars and presented as in situ evidence for aqueous activity. This project seeks to understand (i) the conditions required for jarosite and hematite formation and preservation on planetary surfaces, and (ii) the conditions under which their “radiometric clocks” can be reset (e.g., during changes in environmental conditions such as temperature). By investigating the kinetics of noble gases in minerals, known to occur on Mars and Earth, we will be prepared to analyze and properly interpret ages measured on samples from future Mars sample return missions.

  ROADMAP OBJECTIVES: 1.1 2.1 7.1

• Project 2A: Magnesium Isotope Fractionation Between Brucite [Mg(OH)2] and Mg Aqueous Species

  Recognition of clay minerals on Noachian martian terranes provides important information on the habitability of early Mars. Magnesium isotopic studies can aid in constraining the paleoenvironmental conditions of these clay deposits. Our goal is to conduct Mg isotope exchange experiments between clay minerals and aqueous Mg solutions to better understand how the formation of clay minerals can produce Mg isotope variability. In Mg-bearing phyllosilicates, octahedrally coordinated Mg2+ cations occur in a sheeted structure that is the same as brucite. Determination of Mg isotope fractionation between brucite and aqueous solution, therefore, may provide insight into the origin of Mg isotope variations during weathering and alteration of silicate rocks. Our results document the distinct Mg isotope signals produced by weathering in the presence of organic ligands, raising the possibility that abiotic weathering may be distinguished from biologically-catalyzed weathering using stable Mg isotopes.

  ROADMAP OBJECTIVES: 1.1 2.1 7.1 7.2

• Developing New Biosignatures

  The development and experimental testing of potential indicators of life is essential for providing a critical scientific basis for the exploration of life in the cosmos. In microbial cultures, potential new biosignatures can be found among isotopic ratios, elemental compositions, and chemical changes to the growth media. Additionally, life can be detected and investigated in natural systems by directing cutting-edge instrumentation towards the investigation of microbial cells, microbial fossils, and microbial geochemical products. Over the next five years, we will combine our geomicrobiological expertise and on-going field-based environmental investigations with a new generation of instruments capable of revealing diagnostic biosignatures. Our efforts will focus on creating innovative approaches for the analyses of cells and other organic material, finding ways in which metal abundances and isotope systems reflect life, and developing creative approaches for using environmental DNA to study present and past life.

  ROADMAP OBJECTIVES: 2.1 3.1 4.1 5.1 7.1

• Habitability of Water-Rich Environments, Task 1: Improve and Test Codes to Model Water-Rock Interactions

  Dr. Mikhail Mironenko collaborated with colleagues and completed a code to compute chemical equilibria in low-temperature aqueous systems with salts, CO₂ hydrates, and liquid CO₂. The code could be used to calculate changes in phase composition during freezing or melting in icy cold environments on Mars, large asteroids, icy moons, comets, and trans-neptunian objects. Dr. C. Glein and Dr. E. Shock have published a model to calculate phase chemical equilibria between several hydrocarbons and N₂. The model can be used to explore gas-liquid-solid phase equilibria on Saturn’s moon Titan. Another model has been developed by Dr. Mironenko to calculate condensation of gases in ices and clathrates in the outer solar nebula.

  ROADMAP OBJECTIVES: 2.1 2.2

• Project 2C: Calibrating the ¹³C-¹⁸O (“clumped”) Isotope Temperature Scale

  Determining paleotemperatures in ancient fluid-mineral systems is key to determining ancient habitability. Stable oxygen isotope studies of carbonates have long used changes in ¹⁸O/¹⁶O ratios to infer the temperature from which carbonate precipitated, using a laboratory-calibrated temperature conversion, but this requires knowledge of the ¹⁸O/¹⁶O ratios of the fluid. This is often not known. A relatively new approach is to use the non-random variations in rare C and O isotopes, specifically the preferential enhancement of ¹³C-¹⁸O bonds, which has been shown to be related to temperature and independent of the fluid isotopic composition. Experimental calibrations, however, have been inconsistent, and goal of this project is to reconcile these discrepancies.

  ROADMAP OBJECTIVES: 2.1 4.1 7.1 7.2

• Water and Habitability of Mars and the Moon and Antarctica

  Water plays an important role in shaping the crusts of the Earth and Mars, and now we know it is present inside the Moon and on its surface. We are assessing the water budgets and total inventories on the Moon and Mars by analyzing samples from these bodies.

  We also study local concentrations of water ice on the Moon, Mars, and at terrestrial analogue sites such as Antarctica and Mauna Kea, Hawaii. We are particularly interested in how local phenomena or microclimates enable ice to form and persist in areas that are otherwise free of ice, such as cold traps on the Moon, tropical craters with permafrost, and ice caves in tropical latitudes. We approach these problems with field studies, modeling, and data analysis. We also develop new instruments and exploration methods to characterize these sites. Several of the terrestrial field sites have only recently become available for scientific exploration.

  HI-SEAS (Hawaii Space Exploration Analog and Simulation, hi-seas.org) is a small habitat at a Mars analog site in the saddle area of the Island of Hawaii. It is a venue for conducting research relevant to long-duration human space exploration. We have just completed our first four-month long mission, and are preparing for three more, of four, eight and twelve months in length. The habitat is a 36’ geodesic dome, with about 1000 square feet of floor space over two stories. It is a low-impact temporary structure that can accommodate six crewmembers, and has a kitchen, a laboratory, and a flexible workspace. Although it is not airtight, the habitat does have simulated airlock, and crew-members don mockup EVA suits before going outside. The site is a disused quarry on the side of a cinder/splatter cone, surrounded by young lava fields. There is almost no human activity or plant life visible from the habitat, making it ideal for ICE (isolated/confined/extreme) research.

  ROADMAP OBJECTIVES: 1.1 2.1 3.1 5.3 6.1 6.2 7.1

• Habitability of Water-Rich Environments, Task 4: Evaluate the Habitability of Ancient Aqueous Solutions on Mars

  Co-I Farmer explored for past habitable environments on Mars as part of the MSL (Curiosity) team. He also participated in efforts to develop new life detection instruments for in situ astro-biological exploration of Mars, and documented lipid bio-signature preservation in siliceous hydrothermal deposits.

  Co-I Zolotov developed chemical weathering models for Mars. He argued that formation of salts and phyllo-silicates in the Noachian epoch was followed by aqueous mobilization and deposition of neutral salts in the Hesperian epoch. This hypothesis implies the occurrence of sulfate-saturated subsurface waters during a prolonged time after the formation of phyllo-silicates.

  ROADMAP OBJECTIVES: 2.1

• Project 3A: Banded Iron Formation Deposition Across the Archean-Proterozoic Boundary

  Prior to widespread oxygenic photosynthesis, reduced iron, Fe(II), was the dominant form of soluble iron in surface environments on the early Earth, and likely Mars. On Earth, extensive iron deposits, Banded Iron Formations (BIFs), which currently supply the majority of the iron used in our society, largely formed prior to the Great Oxidation Event of ~2.4 Ga age, and yet contain substantial quantities of oxidized iron, Fe(III). The pathways by which these different oxidation states arose remains unclear. In addition, the chemical and isotopic compositions of BIFs have been used as proxies for ancient seawater or paleoenvironments. In competition with this proposal, however, has been use of BIFs as a tracer of microbial iron cycling. To test the use of BIFs as ambient paleoenvironmental proxies or proxies of microbial process, BIFs from South Africa and Australia were examined from the micron scale to the 100’s of meter scales. We find that BIFs tend to record specific pathways of oxidation of Fe(II), as well as reduction of Fe(III), and extensive post-depositional changes, and it may be quite difficult to infer ambient paleoenvironmental conditions form such deposits.

  ROADMAP OBJECTIVES: 2.1 4.1 5.2 6.1 7.1 7.2

• Project 3B: Carbon Isotope Analysis of Archean Microfossils

  We have completed a study of petrography, Raman microspectroscopy, and in situ analyses of carbon isotope and H/C ratios using secondary ion mass spectrometry (SIMS) of diverse organic microstructures, including possible microfossils. This work has focussed on two localities of the 3.4-billion-year-old Strelley Pool Formation (Western Australia). For the first time, we show that the wide range of carbon isotope ratios recorded at the micrometer scale correlates with specific types of texture for organic matter (OM), arguing against abiotic processes to produce the textural and isotopic relations. These results support the biogenicity of OM in the Strelley Pool Formation.

  ROADMAP OBJECTIVES: 1.1 2.1 4.1 4.2 5.2 6.2 7.2

• Remote Sensing of Organic Volatiles on Mars and Modeling of Cometary Atmospheres

  Using our newly developed analytical routines, Villanueva reported the most comprehensive search for trace species on Mars (Villanueva et al. 2013b, Icarus) and described in detail the chemical taxonomy of comets C/2001 Q4 and C/2002 T7 (de Val-Borro et al. 2013). He expanded our already comprehensive high-resolution spectroscopic database to include billions of spectral lines of ammonia (NH3, Villanueva et al. 2013a), hydrogen cyanide (HCN, Villanueva et al. 2013a, Lippi et al. 2013), hydrogen isocyanide (HNC, Villanueva et al. 2013a), cyanoacetylene (HC3N, Villanueva et al. 2013a), monodeuterated methane (CH3D, Gibb et al. 2013), and methanol (CH3OH, DiSanti et al. 2013). For each species, he developed improved or new fluorescence models using the new spectral models. These permit unprecedented improvement in models of absorption spectra in planetary atmospheres (Earth, Mars), and in computing fluorescence cascades for emission spectra of cometary gases pumped by solar radiation. Villanueva utilized these new models in analyzing spectra of comets that enabled record observations of CO in comet 29P/Schwassmann-Wachmann-1 (see report by Paganini), revealed the unusual organic composition of comet 2P/Encke (see report by Mumma), developed new fluorescence models for the ν2 band of methanol and for the ν3 band of CH3D in comets (see reports by DiSanti and by Bonev), and discovered two modes of water release in comet 103P/Hartley-2 (see report by Bonev).

  ROADMAP OBJECTIVES: 1.1 2.1 3.1 3.2 4.1 7.1

• Understanding the Early Mars Environment

  There is no liquid water on modern Mars, although there is plenty of solid ice. Observations from orbiting satellites and rovers on the ground suggest that liquid water may have flowed over the Martian surface in the distant past. VPL researchers are studying the geologic record of Mars for clues of past water, and investigating climate and chemical conditions under which water would be stable. Team members examined different climate feedbacks and geochemical processes that could have warmed the early Mars. Some members are also active members of the MSL science team.

  This year, team members used climate and interior models to demonstrated that broadening of carbon dioxide and water absorption by volcanically-released hydrogen in Mars early atmosphere may have been enough to raise the mean surface temperature of early Mars above the freezing point of water. We also looked for mechanisms that might have produced the abundant perchlorate molecule found on the Martian surface today.

  ROADMAP OBJECTIVES: 1.1 2.1

• Project 3C: Carbon Isotope Analysis of Proterozoic Microfossils

  We have developed procedures for accurate in situ analysis of carbon isotope ratios by SIMS for individual Precambrian microfossils of unquestioned biogenicity. Data for three Proterozoic localities show a consistent fractionation of 19 per mil between organic matter and coexisting carbonates, in spite of over 6 per mil variability from rock to rock, consistent with fractionations seen for modern cyanobacteria. In one sample, a phytoplanktonic protistan acritarch, found within the same mm-scale domains, are 6 per mil more fractionated, consistent with photosynthetic eukaryotes. These findings show for the first time the possibility of using in situ isotopic microanalysis of fossil microbial mats and ancient sediments in order to distinguish metabolic fingerprints within complex microbial ecosystems and consortia.

  ROADMAP OBJECTIVES: 2.1 4.1 4.2 5.2 7.2

• Taphonomy, Curiosity and Missions to Mars

  MIT team members are actively involved in both the continuing MER and new MSL missions to Mars. Team members are also collaborating on research designed to provide ground truth for remotely sensed clay mineral identifications on Mars, exploring, as well, the relationship between clay mineralogy and organic carbon preservation in sedimentary rocks. For example, our team has been exploring the use of reflectance spectroscopy, which is a rapid, non-destructive technique, for assessing the presence and abundance of organic materials preserved in ancient rocks. Sumner chairs the Gale Mapping Working Group, which is producing geomorphic and geologic maps of the landing area and lower slopes of Mt. Sharp in Gale Crater. This map is being used for long-term planning of science campaigns for Curiosity as well as to put observations into a regional context.

  ROADMAP OBJECTIVES: 2.1 4.1 4.2 6.1 7.1

• Project 4A: Better, Faster, Smaller Fe Isotope Analysis on Iron Oxides and Sulfides by Femtosecond Laser Ablation: Aerosol Characterization and the Influence of Ablation Cells

  New methods are being developed for in situ stable isotope analysis that increase the precision and/or decrease the volume sampled during the analysis. These improvements allow one to identify isotopic anomalies with increasing spatial resolution. We have focused on improving the ablation cell and mass spectrometer electronics to increase the spatial resolution of Fe isotope studies on iron oxides and sulfides whilst maintaining an external precision of +0.2 ‰ in 56Fe/54Fe using femtosecond Laser Ablation (fs-LA) with isotopic analysis by MC-ICP-MS (Micromass “IsoProbe”). These improvements have allowed us to decrease the volume needed for an Fe isotope analysis to ~600μm3 with an external precision of 0.2 ‰ in 56Fe/54Fe (for a typical analysis the laser beam is rastered over an area of 20 by 15 μm). Compared to previous LA Fe isotope studies the volume used for an analysis in an order of magnitude smaller and is similar to Fe isotope studies that have been done by ion microprobe.

  ROADMAP OBJECTIVES: 1.1 2.1 7.1 7.2

• Undergraduate Research Associates in Astrobiology (URAA)

  2013 featured the Tenth URAA offering (Undergraduate Research Associates in Astrobiology), a ten-week residential research program at the Goddard Center for Astrobiology (GCA) (http://astrobiology.gsfc.nasa.gov/education.html). Competition was very keen, with an oversubscription ratio of 3.0. Students applied from over 19 colleges and universities in the United States, and 6 Associates from 6 institutions were selected. Each Associate carried out a defined research project working directly with a GCA scientist at Goddard Space Flight Center or the University of Maryland. As a group, the Associates met with a different GCA scientist each week, learning about his/her respective area of research, visiting diverse laboratories and gaining a broader view of astrobiology as a whole. At summer’s end, each Associate reported his/her research in a power point presentation projected nation-wide to member Teams in NASA’s Astrobiology Institute, as part of the NAI Forum for Astrobiology Research (FAR) Series.

  ROADMAP OBJECTIVES: 1.1 2.1 3.1 6.2 7.1

• The Astrobiology Walk

  The Goddard Center for Astrobiology (GCA) has completed the development and installation of a permanent outdoor exhibit at the Goddard Space Flight Center (GSFC) Visitor Center as a major public outreach effort. The “Astrobiology Walk” is designed to showcase the latest scientific discoveries from the GCA research theme “Search for the Origin and Evolution of Organics” in the context of a timeline for the evolution of the Universe and the Solar System. The exhibit consists of ten outdoor stations situated on the circular pathway around the Visi-tor Center’s “Rocket Garden”, each with a memorable iconic 3D object to convey the main scientific message. QR codes link each placard to web sites relevant to that topic.

  ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 4.1 4.3 7.1 7.2

• Undergraduate Research Associates in Astrobiology (URAA)

  2013 featured the Tenth URAA offering (Undergraduate Research Associates in Astrobiolo-gy), a ten-week residential research program at the Goddard Center for Astrobiology (GCA) (http://astrobiology.gsfc.nasa.gov/education.html). Competition was very keen, with an oversubscription ratio of 3.0. Students applied from over 19 colleges and universities in the United States, and 6 Associates from 6 institutions were selected. Each Associate carried out a defined research project working directly with a GCA scientist at Goddard Space Flight Center or the University of Maryland. As a group, the Associates met with a different GCA scientist each week, learning about his/her respective area of research, visiting diverse la-boratories and gaining a broader view of astrobiology as a whole. At summer’s end, each As-sociate reported his/her research in a power point presentation projected nation-wide to member Teams in NASA’s Astrobiology Institute, as part of the NAI Forum for Astrobiology Research (FAR) Series.

  ROADMAP OBJECTIVES: 1.1 2.1 3.1 6.2 7.1