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2014 Annual Science Report

Pennsylvania State University Reporting  |  SEP 2013 – DEC 2014

Biosignatures in Ancient Rocks - Kasting Group

Project Summary

We have been working on two things: 1) the question of whether there are plausible “false positives” for life on extrasolar planets, i.e., high abiotic O2 and/or O3 levels that might be confused with evidence for photosynthesis, and 2) hydrodynamic escape of hydrogen from H2- or H2O-rich primitive atmospheres. We are developing a two-component model to describe this process. Old single-component models evidently do not obey the diffusion limit, so are are trying to remedy that.

4 Institutions
3 Teams
8 Publications
1 Field Site
Field Sites

Project Progress

We are close to writing a paper on the false positives project. We can reproduce the apparent false positives of other groups (Hu et al., 2012; Domagal-Goldman et al., 2014; Tian et al., 2014), but we can also show that these results are based on an unphysical choice of lower boundary conditions which would not be expected to occur on a real planet.

We also have been working on a variety of other astrobiology projects which are related to the project described here in different ways. See our list of publications for late 2013-2014.

  • PROJECT INVESTIGATORS:
    James Kasting James Kasting
    Project Investigator
  • RELATED OBJECTIVES:
    Objective 1.1
    Formation and evolution of habitable planets.

    Objective 2.1
    Mars exploration.

    Objective 4.1
    Earth's early biosphere.

    Objective 7.2
    Biosignatures to be sought in nearby planetary systems