2009 Annual Science Report

NASA Ames Research Center Reporting  |  JUL 2008 – AUG 2009

Executive Summary

This report summarizes the efforts of the current Ames Team during the first nine months of the CAN-5 performance period and the final efforts of the previous Ames Team under CAN-3. The Ames CAN-3 Team addressed the development of habitable planetary environments, the origins of biological functions, biosignatures created by microbial ecosystems fueled by light or by chemical energy, and the survival of life in space and in changing environments on Earth.

The current Ames Team addresses the cosmochemical, planet-forming, geochemical, and biological processes that combine to create habitable environments. We trace, spectroscopically, the cosmic evolution of organic molecules from the interstellar medium to protoplanetary disks, planetesimals and finally onto habitable bodies. We characterize the diversity of planetary systems emerging from protoplanetary disks, with a focus on the formation of planets that provide chemical raw materials, energy, and environments necessary to sustain prebiotic chemical evolution ... Continue reading.

Field Sites
25 Institutions
6 Project Reports
73 Publications
1 Field Site

Project Reports

  • Interplanetary Pioneers – Final CAN-3 Report

    The possibility of life traveling from earth to beyond, and, in general, life traveling from planet to planet, has captured the public’s imagination for a century or more. We are now poised to assess this possibility with experimentation. In this project, we focus on halophiles – organisms that live in high salt environments – as potential earth life to survive space travel. Thus we have explored high UV and high salt environments, and have flown some of these organisms on European space missions. This year we also began to develop the use of high altitude ballooning to mimic travel beyond the surface of the earth.

    ROADMAP OBJECTIVES: 5.3 6.2
  • Origins of Functional Proteins and the Early Evolution of Metabolism

    The main goal of this project is to identify critical requirements for the emergence of biological complexity in early habitable environments by examining key steps in the origins and early evolution of catalytic functionality and metabolic reaction networks. Using proteins, which are the main catalytic agents in terrestrial organisms, we investigate whether enzymatic activity can arise from an inventory of polymers that have random sequences and that might have existed in habitable environments. We attempt the first demonstration of multiple origins of a single enzymatic function, and investigate experimentally how primordial proteins could evolve through the diversification of their structure and function. Building on this work and on our knowledge of ubiquitous protocellular functions and the constraints of prebiotic chemistry, we conduct computer simulations to elucidate fundamental principles that govern the coupled evolution of early metabolic reactions and their catalysts.

    ROADMAP OBJECTIVES: 3.2 3.4
  • Cosmic Distribution of Chemical Complexity

    This project seeks to improve our understanding of the connection between chemistry in space and the origin of life on Earth and possibly other worlds. Our approach is to trace the formation and development of chemical complexity in space, with particular emphasis on understanding the evolution from simple to complex species focusing on those that are interesting from a biogenic perspective and also understanding their possible roles in the origin of life on habitable worlds. We do this by first measuring the spectra and chemistry of materials under simulated space conditions in the laboratory. We then use these results to interpret astronomical observations made with ground-based and orbiting telescopes. We also carry out experiments on simulated extraterrestrial materials to analyze extraterrestrial samples returned by NASA missions or that fall to Earth in meteorites.

    ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.2 3.4 4.3 7.1 7.2
  • Ecosphere to Biosphere Modeling – Final CAN-3 Report

    We have created a working model of a microbial mat called MBGC (for Microbial Biogeochemistry). The model examines the internal cycling of oxygen, carbon, and sulfur through a complex microbial ecosystem that may be similar to those found on early earth.

    ROADMAP OBJECTIVES: 4.1 5.3 6.1
  • Mineralogical Traces of Early Habitable Environments

    The goal of our work is to discern the habitability (potential to support life) of ancient Martian environments, with an emphasis on understanding which environments could have supported life more abundantly than others. This information will help to guide the selection of sites on the Martian surface, for future missions designed to seek direct evidence of life. Our approach has two main parts: 1. We will use the presence of specific minerals or groups of minerals – an analysis that can be performed robotically on Mars — to constrain the chemical and physical conditions of the ancient environments in which they formed. 2. We will work to understand how the ability of environments on Earth to support more or less biomass depends on these same physical and chemical conditions.

    ROADMAP OBJECTIVES: 2.1
  • 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 its surface, it lies within the so-called “habitable zone.” The goal of this project is to understand the formation process and identification of such life-supporting bodies.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.3