2009 Annual Science Report

Pennsylvania State University Reporting  |  JUL 2008 – AUG 2009

Executive Summary

The Penn State Astrobiology Research Center (PSARC) has charted a new direction focused on the recognition and characterization of microbial life, past and present. At the core of Astrobiology and at the forefront of NASA goals is the construction of a fundamental scientific knowledge base that enables the recognition of signatures of life on the early Earth, in extreme environments, and in extraterrestrial settings. Our new work focuses on four major projects: (1) Developing New Biosignatures, (2) Biosignatures in relevant microbial ecosystems, (3) Biosignatures in ancient rocks, and (4) Biosignatures in extraterrestrial settings.

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 ... Continue reading.

Field Sites
32 Institutions
4 Project Reports
65 Publications
11 Field Sites

Project Reports

  • Biosignatures in Extraterrestrial Settings

    This project looks at the evolution of the composition of gases in the cold disk from which planets form; the evolution of the atmosphere after planet formation, in particular, the role of trace gases in the early greenhouse effect; and, some aspects of the the formation and later dynamical evolution of extrasolar planets.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1
  • 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
  • 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