2009 Annual Science Report
Massachusetts Institute of Technology Reporting | JUL 2008 – AUG 2009
Modelling Planetary Albedo
What kind of environments could provide opportunities for life in general and for the advent of complex life specifically to emerge? If there were complex life present, what features would it produce? Could we remotely characterize such habitats and the features of complex life on extrasolar planets light-years away with current and future NASA missions?
These are the three main questions we work on in this part of the project.
LK & DS Worked on the global surface environment and remote detectability of terrestrial planets with alternative geochemical cycles (paper on atmospheric signatures of a SO2 cycle submitted). Enhanced concentrations of SO2 are clearly detectable with future NASA space missions. Sulfur dominated environments are of general interest as alternatives for the emergence of alien biochemistries both for early conditions for life as well as an environment for the advance of complex life (see Fig.1). In addition aerosols due to sulfur could affect albedos on such planets and influence the climate as well as the location of the Habitable Zone.
In a separate effort, in collaboration with Roger Fu and Richard O’Connell (Harvard EPS) DDS developed models of the dynamics of the interiors and LK developed models of detectable features of water dominated super-Earths (see Fig.2), the paper is submitted. In addition to the scientific publication this also created great interest in the media (even so unpublished for now) and was taken up by the History Channel as part of their Liquid Universe show (interviewing LK) as well as the Discovery Channel (interviewing DS).
LK in collaboration with Charles Cockell and John Raven (microbiologists UK) developed and published models for remotely detectable features of planetary environments that are dominated by cryptic photosynthesis (see Figure 3), quantifying the production of oxygen by cryptic photosynthesis on an earth-like exoplanet and assessing the remotely detectable features of such worlds for nest generation NASA space missions.
LK calculated and submitted papers on the detectability of simple and advanced life remotely on exoplanets as well as the influence of host stars on the potentially habitability of planetary environments. It also provides a step to step approach on how to characterize a habitable world with low to higher resolution measurements in accordance from future NASA mission concepts.
PROJECT MEMBERS:Lisa Kaltenegger
RELATED OBJECTIVES:Objective 1.1
Formation and evolution of habitable planets.
Indirect and direct astronomical observations of extrasolar habitable planets.
Earth's early biosphere.
Production of complex life.
Adaptation and evolution of life beyond Earth
Biosignatures to be sought in nearby planetary systems