2010 Annual Science Report

Astrobiology Roadmap Objective 1.2 Reports Reporting  |  SEP 2009 – AUG 2010

Project Reports

  • Project 1: Looking Outward: Studies of the Physical and Chemical Evolution of Planetary Systems

    We study the origin of life through a wide variety of approaches, beginning here with theoretical investigations of protoplanetary disks, the environments in which simple organic molecules first appeared and were concentrated in planetary bodies. We also study the survival of this organic matter during subsequent evolution through observations of circumstellar disks around both young and mature stars, extrasolar planetary systems, and small bodies in our Solar System, and through detailed models of planetary system formation.

    ROADMAP OBJECTIVES: 1.1 1.2 2.2 3.1
  • AIRFrame Technical Infrastructure and Visualization Software Evaluation

    The Astrobiology Integrative Research Framework (AIRFrame) analyzes published and unpublished documents to identify and visualize implicit relationships between astrobiology’s diverse constituent fields. The main goal of the AIRFrame project is to allow researchers and the public to discover and navigate across related information from different disciplines.

    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
  • AbGradCon 2010

    The Astrobiology Graduate Student conference is a conference organized by astrobiology graduate students for astrobiology grad students. It provides a comfortable peer forum in which to communicate and discuss research progress and ideas.

    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
  • Detectability of Life

    Detectability of Life investigates the detectability of chemical and biological signatures on the surface of icy worlds, with a focus on spectroscopic techniques, and on spectral bands that are not in some way connected to photosynthesis.Detectability of life investigation has three major objectives: Detection of Life in the Laboratory, Detection of Life in the Field, and Detection of Life from Orbit.

    ROADMAP OBJECTIVES: 1.2 2.1 2.2 4.1 5.3 6.1 6.2 7.1 7.2
  • Disks and the Origins of Planetary Systems

    This task is concerned with understanding the evolution of complexity as primitive planetary bodies form in habitable zones. The planet formation process begins with fragmentation of large molecular clouds into flattened protoplanetary disks. This disk is in many ways an astrochemical “primeval soup” in which cosmically abundant elements are assembled into increasingly complex hydrocarbons and mixed in the dust and gas envelope within the disk. Gravitational attraction among the myriad small bodies leads to planet formation. If the newly formed planet is a suitable distance from its star to support liquid water at the surface, it is in the so-called “habitable zone.” The formation process and identification of such life-supporting bodies is the goal of this project.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.3
  • Biosignatures in Extraterrestrial Settings

    The team will investigate the abundance of sulfur gases and elucidate how these gases can be expected to evolve with time on young terrestrial planets. They will continue studies of planet formation in the presence of migration and model radial transport of volatiles in young planetary systems, and will be involved with searches for M star planetary companions and planets around K-giant stars.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 4.1 4.3 6.2 7.1
  • Astronomical Observations of Planetary Atmospheres and Exoplanets

    This task encompasses remote-sensing observations of Solar System and extrasolar planets made by the VPL team. These observations, while providing scientific exploration in its own right, also allow us to test our planetary models and help advance techniques to retrieve information from the astronomical data that we obtain. This can include improving our understanding of the accuracy of inputs into our models, such as spectral databases. This year we made and/or analyzed observations of Venus and Titan taken by ground-based and spaceborne observatories, and improved models for extrasolar hot Jupiters.

    ROADMAP OBJECTIVES: 1.2 2.2
  • Path to Flight

    Our technology investigation, a Path to Flight for astrobiology, utilizes instrumentation built with non-NAI funding to carry out three science investigations namely habitability, survivability and detectability of life. The search for life requires instruments and techniques that can detect biosignatures from orbit and in-situ under harsh conditions. Advancing this capacity is the focus of our Technology Investigation.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 7.1 7.2
  • Detectability of Biosignatures

    In this project VPL team members explore the nature and detectability of biosignatures, global signs of life in the atmosphere or on the surface of a planet. Work this year focused on the build up and detectability of sulfur-based biosignatures in early Earth-like atmospheres, especially for planets orbiting stars cooler than our Sun. We also explored the potential non-biological generation of oxygen and ozone in early Earth-like atmospheres, which could result in a “false positives” for photosynthetic life. In parallel, we worked on acquiring and getting running two simulators for telescopes that will one day be able to observe and determine the properties of extrasolar terrestrial planets.

    ROADMAP OBJECTIVES: 1.1 1.2 4.1 6.2
  • Bioastronomy 2007 Meeting Proceedings

    This is the published volume of material from an astrobiology meeting hosted by our lead team in 2007 in San Juan Puerto Riceo. The book includes 60 papers covering the breadth of astrobiology, and developed a new on-line astrobiology glossary.

    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
  • Dynamical Effects on Planetary Habitability

    VPL explored numerous features of orbits. We showed that comets are unlikely to have produced more than 1 mass extinction event in the past 500 million years. We catalogued the fractions of habitable zones of nearby stars that are capable of supporting a habitable planet. We also participated in the discovery of two planets whose orbital planes are offset by 30 degrees.

    ROADMAP OBJECTIVES: 1.1 1.2 4.3
  • Computational Astrobiology Summer School

    The Computational Astrobiology Summer School (CASS) is an excellent opportunity for graduate students in computer science and related areas to learn about astrobiology, and to carry out substantial projects related to the field.

    The two-week on-site part of the program is an intensive introduction to the field of astrobiology. NASA Astrobiology Institute scientists present their work, and the group discusses ways in which computational tools (e.g. models, simulations, data processing applications, sensor networks, etc.) could improve astrobiology research. Also during this time, participants define their projects, with the help of the participating NAI researchers. On returning to their home institutions, participants work on their projects, under the supervision of a mentor, with the goal of presenting their completed projects at an astrobiology-related conference the following year.

    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
  • PHL 278: A Gateway Course for a Minor in Astrobiology

    We have recently developed obtained Montana Board of Regents for an undergraduate minor in Astrobiology at Montana State University. The Minor includes courses in Earth Sciences, Physics, Astronomy, Microbiology, Ecology, Chemistry, and Philosophy. Two new courses have been developed as part of the minor, one of which is a gateway or introductory course examines the defining characteristics of life on earth as well as the challenges of a science that studies life and its origin. The other course which will be offered fall 2011 is the capstone course for the minor which will delved into the science of Astrobiology in more detail and targeted for Juniors and Seniors that have fulfilled the majority of the requisite course requirements for the curriculum.

    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
  • Earth as an Extrasolar Planet

    Earth is the only known planet that can support life on its surface, and serves as our only example of what a habitable planet looks like. This task uses distant observations of the Earth taken from spacecraft combined with a sophisticated computer model of the Earth to understand the appearance and characteristics of a habitable planet. With our model, we can generate accurate simulations of the Earth’s brightness, color and spectrum, when viewed at different time-intervals, and from different vantage points. We are using these simulations to understand how we might detect signs of an ocean on a distant planet, and to understand the limitations of surface temperature measurements when a planet has significant cloud cover.

    ROADMAP OBJECTIVES: 1.2 7.2
  • Formation of Terrestrial Planets

    This past year VPL has continued to explore key unknowns in our understanding of terrestrial planet formation. We have performed supercomputer simulations of the early formation of the Earth, and found that it can proceed more quickly than previously appreciated and suggests terrestrial exoplanets may be common. We also showed how the shape of belts of asteroids in the outer reaches of planetary systems, which can be directly observable, provide clues to the layout of the interior planets, which are often not observable.

    ROADMAP OBJECTIVES: 1.1 1.2 3.1 4.3
  • Evolution of Protoplanetary Disks

    Drs. Aki Roberge and Carol Grady are pursuing studies related to Theme 2 of the NASA GSFC Astrobiology Node, “From Molecular Cores to Planets: Our Interstellar Heritage.” Over the last year, they have begun work on two Open Time Key Projects for the Herschel Space Observatory, an ESA mission launched in May 2009. Herschel is expected to spearhead the next big advances in our knowledge of planet formation, protoplanetary disk evolution, and debris disks. One project (GASPS) will illuminate the evolution of gas abundances and chemistry in protoplanetary disks over the planet-forming phase. The other (DUNES) will sensitively probe the Sun’s nearest neighbors for signs of cold debris disks associated with extrasolar Kuiper Belts. Both projects have begun to produce exciting results, including discovery of a possible new class of ultra-cold debris disks that challenge theories of debris disk evolution and planet formation.

    ROADMAP OBJECTIVES: 1.1 1.2 3.1 3.2
  • Planetary Surface and Interior Models and SuperEarths

    We use computer models to simulate the evolution of the interior and the surface of real and hypothetical planets around other stars. Our goal is to work out what sorts of initial characteristics are most likely to contribute to making a planet habitable in the long run. Observations in our own Solar System show us that water and other essential materials are continuously consumed via weathering (and other processes) and must be replenished from the planet’s interior via volcanic activity to maintain a biosphere. The surface models we are developing will be used to predict how gases and other materials will be trapped through weathering over time. Our interior models are designed to predict how much and what sort of materials will come to a planet’s surface through volcanic activity throughout its history.

    ROADMAP OBJECTIVES: 1.1 1.2 4.1 5.2 6.1
  • Modelling Planetary Albedo & Biomarkers in Rocky Planets’/moons Spectra

    The recent discovery of several potentially habitable Super-Earths (planets up to about 10x the mass of our own Earth that could be rocky) and the first nearby super-Earth planets around the habitable Zone of Gl581, has proven that we can already detect potentially habitable planets and makes this research extremely relevant. We model atmospheric spectral signatures, including biosignatures, of known and hypothetical exoplanets that are potentially habitable.
    The atmospheric characterization of such Super-Earths and potentially habitable Moons, will allow us to explore the condition on the first detectable rocky exoplanets and potentially characterize the first detectable Habitable Exoplanet.

    ROADMAP OBJECTIVES: 1.1 1.2 4.1 4.2 6.2 7.2
  • Postdoctoral Fellow Report: Mark Claire

    I am interested in how biological gases affect the atmosphere of Earth (and possibly other planets.) Specifically, I use computer models to investigate how biogenic sulfur gases might build up in a planetary atmosphere, and if this would lead to observable traces in Earth’s rock record or in the atmospheres of planets around other stars. I’ve also worked on how perchlorate formed in Earth’s Atacama desert as an attempt to explain how perchlorate formed on Mars

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 7.2
  • Detection of Terrestrial Planets Around M Stars

    We have carried out an extensive search for small extrasolar planets around M stars in the solar neighborhood. Our search is focused on planets in the habitable zone. We have been able to detect 4 planets around M stars, among which an Earth-like planet in the habitable zone of star GL 581.

    ROADMAP OBJECTIVES: 1.2
  • NIR Spectroscopic Observations of Circumstellar Disks Around Young Stars

    Using the NIRSPEC instrument on the Keck telescope in collaboration with Dr. Michael Mumma of NASA GSFC and Dr. Geoffrey Blake of CalTech, we made the first discovery of OH ro-vibrational emission in the L band (3 – 4 μm) in the planet-forming (1-10 AU) region of disks around Herbig Ae stars (Mandell et al. 2008). OH is a sensitive tracer of the UV and IR radiation field and the dissociation and recombination of H2 and H2O, and combined with a strong upper limit for H2O emission these observations provide a sensitive constraint on the formation and destruction rate of water and the vertical height of the dust absorbing layer. Line strengths are characteristic of temperatures of ~600K, and the location is constrained to beyond ~1 AU by the spectral line widths, suggesting we are observing the warm molecular layer beyond the inner dust rim.

    ROADMAP OBJECTIVES: 1.1 1.2 3.1 7.2
  • Formation and Prospect of the Detection of Habitable Super-Earths Around Low-Mass Stars: Reconciling Theory With Observation

    We have studied the formation of terrestrial planets around M stars with a migrating giant planet. Results indicate that terrestrial planet formation is possible at somewhat large distances where the giant planet captures the terrestrial body in resonance, and the two objects migrate to close-in orbits.

    ROADMAP OBJECTIVES: 1.1 1.2
  • Stellar Effects on Planetary Habitability

    Habitable environments are most likely to exist in close proximity to a star, and hence a detailed and comprehensive understanding of the effect of the star on planetary habitability is crucial in the pursuit of an inhabited world. We looked at how the Sun’s brightness would have changed with time. We also model how stars with different masses, temperatures and flare activity affect the habitability of planets, including looking at the effect of a very big flare on a planet’s atmosphere and surface. We find that a planet with an atmosphere like Earth orbiting around a cool red star is fairly well protected from UV radiation, but particles associated with the flare can produce damaging chemistry in the planetary atmosphere that severely depletes the planet’s ozone layer.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 4.3 5.3 6.1 7.2
  • The VPL Life Modules

    The Life Modules of the VPL are concerned with the modeling of biosphere processes for coupling with the VPL’s atmospheric and planetary models. These coupled models enable simulation of the impact of biogenic gases on atmospheric composition, of biota on the surface energy balance, and of the detectability of these in planetary spectra. The Life Modules team has engaged in previous work coupling 1D models in the VPL’s suite of planetary models, and current work now focuses on biosphere models coupled to 3D general circulation models (GCMs). Current project areas are: 1) development of a model of land-based ecosystem dynamics suitable for coupling with GCMs and generalizable for alternative planetary parameters, and 2) coupling of an ocean biogeochemistry model to GCMs.

    ROADMAP OBJECTIVES: 1.2 6.1 6.2 7.2
  • Understanding Past Earth Environments

    We study the chemical and climate evolution of the Earth as the best available proxy for what other inhabited planets might be like. A particular focus is on the “Early Earth” (formation through to the 1.6 billion years ago) which is poorly represented in the geological record but comprises half of Earth’s history. We have studied the total pressure of the Archean atmosphere (prior to 2.5 billion years ago), developed constraints on CO2 concentration, studied the oxygen and nitrogen cycles, the fractionation of sulfur isotopes and explored the effect of hazes on early Earth climate.

    ROADMAP OBJECTIVES: 1.1 1.2 4.1 4.2 5.1 5.2 6.1
  • VPL Databases, Model Interfaces and the Community Tool

    The Virtual Planetary Laboratory develops modeling tools and provides a collaborative framework for scientists from many disciplines to coordinate research on the environments of extrasolar planets. As part of this framework, the VPL acts as a central repository for planetary models and the inputs required to generate those results. Developing a comprehensive storehouse of input data for computer simulations is key to successful collaboration and comparison of the models. As part of the on-going VPL Community Tools, we are developing a comprehensive database of molecular, stellar, pigment, and mineral spectra useful in developing extrasolar planet climate models and interpreting the results of NASAs current and future planet-finding missions. The result, called the Virtual Planetary Spectral Library, provides a common source of input data for modelers and a single source of comparison data for observers.

    ROADMAP OBJECTIVES: 1.1 1.2
  • Quantification of the Disciplinary Roots of Astrobiology

    While astrobiology is clearly an interdisciplinary science, this project seeks to address the question of how interdisciplinary it is. We are reviewing published works across a broad range of scholarly databases, comparing disciplinary indicators such as subject terms, journal titles and author affiliations, and creating a computational model to identify and compare the makeup of astrobiological research literature in terms of the proportion of work that come from constituent fields.

    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
  • VYSOS Construction

    The VYSOS project aims at surveying all the major star forming regions all across the entire northern and southern sky for variable young stars. Two small survey telescopes have been purchased and provide large area shallow observations, and two larger telescopes allow
    deeper more detailed observations. All observations are done robotically.

    ROADMAP OBJECTIVES: 1.2