2009 Annual Science Report

Astrobiology Roadmap Objective 5.2 Reports Reporting  |  JUL 2008 – AUG 2009

Project Reports

  • Biosignatures in Ancient Rocks

    The Earth’s Archean and Proterozoic eons offer the best opportunity for investigating a microbial world, such as might be found elsewhere in the cosmos. The ancient record on Earth provides an opportunity to see what geochemical signatures are produced by microbial life and how these signatures are preserved for geological time. Researchers have recognized a variety of mineralogical and geochemical characteristics in ancient rocks (sedimentary and igneous rocks; paleosols) that may be used as indicators of: (i) specific types of organisms that lived in the oceans, lakes and on land; and (ii) their environmental conditions (e.g., climate; atmospheric and oceanic chemistry). Our project addresses the following questions: Are some or all of these characteristics true or false signatures of organisms and/or indicators of specific environmental conditions? Do a “biosignature” in a specific geologic formation represent a local or global phenomenon? How are the biosignatures on Mars and other planets expected to be similar to (or different from) those in ancient terrestrial rocks?

    ROADMAP OBJECTIVES: 1.1 3.2 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • AbGradCon 2009

    The Astrobiology Graduate Student Conference (AbGradCon) was held on the UW campus July 17 – 20 2009. AbGradCon supports NAI’s mission to carry out, support and catalyze collaborative, interdisciplinary research, train the next generation of astrobiology researchers, provide scientific and technical leadership on astrobiology investigations for current and future space missions, and explore new approaches using modern information technology to conduct interdisciplinary and collaborative research amongst widely-distributed investigators. This was done through a diverse range of activities, ranging from formal talks and poster sessions to free time for collaboration-enabling discussions, social activities, web 2.0 conference extensions, public outreach and grant writing simulations.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • AIRFrame Technical Infrastructure and Visualization Software Evaluation

    To create visualizations of interdisciplinary relationships in the field of astrobiology, this component of the AIRFrame project involves creating a data model for source documents, a database structure, and evaluating off-the-shelf visualization software for possible application to the final project.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Advancing Methods for the Analyses of Organics Molecules in Microbial Ecosystems

    Eigenbrode’s GCA work over the past year has largely focused on advancing protocols for the extraction and analysis of complex organics molecules in iron-oxide rich samples regarded as analogs to groundwater seeps and ancient surface water environments on Mars and ancient Earth. Eigenbrode has succeeded with some advance in methods for organic extraction and analysis for samples that include iron seep sediments, cultured iron bacteria, and terrace sediments of the Rio Tinto. In addition, Eigenbrode has been part of a successful study aimed at understanding microbial metabolisms and ecological evolution of Neoarchean using Fe, S, and C isotopic records.

    ROADMAP OBJECTIVES: 2.1 4.1 5.1 5.2 5.3 6.1 7.1
  • Evolution of Nitrogen Fixation, Photosynthesis, Hydrogen Metabolism, and Methanogenesis

    We have developed a new line of investigation to complement our work on the biochemistry of complex iron-sulfur cluster enzyme structure, function and biosynthesis with the aim of probing complex iron-sulfur enzyme evolution. We are studying the phylogenetic trajectory of multiple genes involved in complex iron-sulfur cluster function and biosynthesis to probe the evolutionary origin of aspect of hydrogen metabolism and modes of biological nitrogen fixation.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Biosignatures in Relevant Microbial Ecosystems

    In this project, PSARC team members explore the isotope ratios, gene sequences, minerals, organic biomarkers, and other biosignatures in modern ecosystems that function as analogs for early earth ecosystems, or for life that may be present elsewhere in the solar system and beyond. Many of these environments are “extreme” by human standards and/or have conditions that are at the limit for microbial life on Earth.

    ROADMAP OBJECTIVES: 4.1 4.3 5.1 5.2 5.3 6.1 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 2.2 3.1 3.4 4.1 5.2 5.3 7.1 7.2
  • Bioastronomy 2007 Meeting Proceedings

    The 9th International Bioastronomy coneference: Molecules, Microbes and Extraterrestrial Life was organized by Commission 51 (Bioastronomy) of the International Astronomical Union, and by the UH NASA Astrobiology team. The meeting was held in San Juan, Puerto Rico from 16-20 July 2007. During the reporting period the Proceedings were finalized and will have a publication date of 2009.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • CASS Planning

    The computational astrobiology summer school (CASS) is a two week program, followed by a semester of mentored independent work, which has the following goals:

    - To introduce computer science and engineering (CS&E) graduate students to the field of astrobiology, – To introduce astrobiologists to the tools and techniques that current methods in CS&E can provide, and – To encourage interdisciplinary projects that will result in advances in astrobiology.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Metabolic Networks From Single Cells to Ecosystems

    Metabolic networks perform some of the most fundamental functions in living cells, including energy transduction and building block biosynthesis. While these are the best characterized networks in living systems, understanding their evolutionary history and complex wiring is still a major open question in biology. Here we use mathematical models and computer simulations to understand how metabolic networks gradually evolved the degree of organization necessary to sustain complex multicellular life. In particular, we ask (i) how metabolism changed as the level of oxygen gradually rose in the atmosphere, (ii) what metabolic structures are associated with cell-cell communication, and (iii) whether general optimality principles can help understand the architecture of biochemical networks.

    ROADMAP OBJECTIVES: 4.1 4.2 5.2 6.1
  • Iron Isotope Biosignatures: Laboratory Studies and Modern Environments

    The isotopic fingerprints of biological carbon and sulfur cycling in modern and ancient marine environments is well established by research over several decades, but, until recently, potential iron isotope fingerprints of microbial iron cycling in the ancient Earth have not been pursued. Next to carbon, iron was probably the most important element cycled by early life, given the high abundance of iron in early Earth environments and the energy gains that may be obtained by microbes during iron redox changes. Our new laboratory studies moved away from simple systems to those more analogous to nature, and we demonstrated that iron isotope fractionations can be produced by biological cycling in complex systems. Moreover, in a field study, we isolated natural iron cycling microbes and demonstrated that the iron isotope fractionations produced by natural microbial ecosystems are the same as those produced by pure strains in the laboratory; these are key components to confidently applying Fe isotopes as a biosignature for ancient life.

    ROADMAP OBJECTIVES: 2.1 4.1 5.2 6.1 7.1 7.2
  • Planetary Surface and Interior Models and SuperEarths

    In this project, we model the processes that continually reshape the interiors and the surfaces of terrestrial (rocky) planets. The models we develop and use give us insight into how these processes (e.g. weathering, volcanism, and plate tectonics) affect a planet’s habitability as the planet evolves. In addition to Earth- and Mars-like planets, we now seek to model two sorts of planets not observed in our Solar System: 1) “super-Earths” (rocky planets up to 10 times as massive as Earth) and 2) planets so close to their star that the tides actually heat the interior of the planet.

    ROADMAP OBJECTIVES: 1.1 1.2 4.1 5.2 6.1
  • Subglacial Methanogenesis and Its Role in Planetary Carbon Cycling

    Methanogens are thought to be among the earliest emerging life forms. Today, the distribution of methanogens is narrowly constrained, due in part to the energetics of the reactions which support this functional class of organism (namely carbon dioxide reduction with hydrogen and acetate fermentation). Methanogens utilize a number of metalloenzymes that have active site clusters comprised of a unique array of metals. The goals of this project are 1) identifying a suite of biomarkers indicative of biological CH4 production 2). quantifying the flux of CH~4~ from sub-ice systems and 3). developing an understanding how life thrives at the thermodynamic limits of life. This project represents a unique extension of the ABRC and bridges the research goals of several nodes, namely the JPL-Icy Worlds team and the ASU-Follow the Elements team.

    ROADMAP OBJECTIVES: 2.1 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Viral Ecology and Evolution

    This project is aimed at probing the occurrence and evolution of archaeal viruses in the extreme environments in the thermal areas in Yellowstone National Park. Viruses are the most abundant life-like entities on the planet and are likely a major reservoir of genetic diversity for all life on the planet and these studies are aimed at providing insights into the role of viruses in the evolution of early life on Earth.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Deep Biosphere Workshop

    This is a Workshop on the use of borehole CORK observatories for microbiological and hydrogeological studies. It is planned to be an international workshop including European and Asian participation. We are also actively targeting early career researchers and those not yet actively involved in deep marine CORK observatory research.

    ROADMAP OBJECTIVES: 4.2 5.2 5.3 6.1 6.2
  • Stoichiometry of Life, Task 1: Laboratory Studies in Biological Stoichiometry

    Living things require a broad menu of chemical elements to function. This project aims to quantify the chemical elements required by prokaryotes – the class of terrestrial organisms thought most similar to those that might be present in extraterrestrial settings – through laboratory experiments. These experiments will also teach us the ways in which such organisms cope with scarcity of the bioessential elements nitrogen, phosphorus and iron. We are also conducting experiments to isolate micro-organisms that use the element arsenic in place of phosphorus, if they exist. In Year 1 we initiated the first stage of these experiments.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.1
  • Stromatolites in the Desert: Analogs to Other Worlds

    Cuatro Cienegas Basin, a desert oasis in the Chihuahua desert of central Mexico, provides a proxy for an earlier time in Earth’s history when microbes dominated the scenery. The basin hosts active, growing stomatolites, communities of microbes that are covered in carbonates, principally through the action of metabolic processes within the community. Researchers from several NAI teams are actively researching and creating experimental procedures to understand small scale and large scale evolution within these communities, using tools from biology, geology, and astronomy.

    ROADMAP OBJECTIVES: 4.1 4.2 5.2 5.3 6.1 6.2
  • Developing New Sampling System, Collection of Juan De Fuca Ridge Basement Fluids

    Our Deep Biosphere project is designed to exploit the unprecedented opportunities provided by the new generation of long-term borehole- observatories installed on the flanks of the Juan de Fuca Ridge (JdFR) by the Integrated Ocean Drilling Program, to study the microbial geochemistry and ecology of the sediment-buried ocean basement. The Drill ship drills deep holes through the sediments into the underlying basaltic rocks and then installs a 'CORK’ observatory consisting of casings, fluid delivery lines with seafloor access-spigots, downhole instruments, and a top plug.

    ROADMAP OBJECTIVES: 3.2 3.3 4.1 5.2 5.3
  • Stoichiometry of Life, Task 2a: Field Studies – Yellowstone National Park

    We are investigating how the element requirements of microbes are affected by element availability in their environment in Yellowstone National Park, where there are extreme variations in the abundances of bioessential elements in addition to extremes of temperature and pH. In Year 1 we organized a multi-disciplinary field expedition to collect samples and conduct experiments. Analyses of these samples is now underway.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.2
  • Stoichiometry of Life, Task 2b: Field Studies – Cuatro Cienegas

    Cuatro Cienegas is a unique biological preserve in which there is striking microbial diversity, potentially related to extreme scarcity of phosphorus. We aim to understand this relationship.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2
  • Understanding Past Earth Environments

    This project examines the evolution of the Earth over time. This year we examined and expanded the geological record of Earth’s history, and ran models to help interpret those data. Models were also used to simulate what the early Earth would look like if viewed remotely through a telescope similar to NASA’s Terrestrial Planet Finder mission concept. We focused our efforts on the Earth as it existed in prior to and during the rise of atmospheric oxygen 2.4 billion years ago, as this was one of the most dramatic and important events in the evolution of the Earth and its inhabitants.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 4.2 4.3 5.1 5.2 5.3 6.1
  • Stoichiometry of Life, Task 3b: Ancient Records – Genomic

    The genomic records of modern organisms carry clues to the evolution of the use of elements in biology. We are investigating these records in several ways, with a particular emphasis on the use of metals in enzyme active sites and nitrogen fixation.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3
  • Stoichiometry of Life, Task 4: Biogeochemical Impacts on Planetary Atmospheres

    The abundance of molecular oxygen in planetary atmospheres may be a useful way to look for evidence of life. The amount of photosynthetically produced oxygen that accumulates in an atmosphere depends in part on the export of photosynthetically produced organic carbon from the ocean surface to the seafloor, which in turn may depend on the availability of bioessential elements. We are using a computer model to determine how this carbon export processes might operate in an ocean dominated by prokaryotes rather than eukaryotes, as may have been common in Earth’s past and as an analog for hypothetical extrasolar planets.

    ROADMAP OBJECTIVES: 4.1 4.2 5.2 6.1 7.2
  • Nordic-UHNAI Astrobiology Summer School – Iceland 2009

    In collaboration with the Nordic Astrobiology Network, we organized an astrobiology summer school held in Iceland from Jun 29-Jul 13, 2009. Participants included 19 graduate students from the US, and 24 students from 16 countries, with a focus on Nordic participants. Activities during the two week program included lectures on the topics of Water, Ice and the Origin of Life in the Universe, a student poster session, field sampling on thermophiles, and labwork and computer modeling activities.

    ROADMAP OBJECTIVES: 2.2 3.1 5.2 5.3
  • Quantification of the Disciplinary Roots of Astrobiology

    The questions of astrobiology span many scientific fields. This project analyzes databases of scientific literature to determine and quantify the diverse disciplinary roots of astrobiology. This is one component of a wider study to build a map of relationships between the constituent fields of astrobiology, so relevant knowledge in diverse fields can be most efficiently inform the study of life in the universe.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2