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Project Progress

This project covers the general aspects of the assembly and input data collection for the Virtual Planetary Laboratory (VPL). The VPL is anticipated to be a suite of versatile computer models that can be used to derive a range of plausible atmospheres and surfaces for extrasolar terrestrial planets, and to produce synthetic spectra of what these planets would look to an astronomical observer. The VPL will consist of the coupling of 3 existing atmospheric models dealing with radiative transfer, climate and chemistry. The boundary conditions for this coupled model will be provided by newly derived programming modules that characterise geological and biological processes at the surface of the planet, and exogenic processes between space and the top of the atmosphere.

To act as a test and development machine, a 32-processor Linux Beowulf cluster was purchased to accelerate the implementation of our existing radiative transfer models for use on parallel computing architectures. This facility is now on line. The line-by-line model for gas absorption, LBLABC has been successfully ported to this machine and its results have been validated. The Spectral Mapping Atmospheric Radiative Transfer (SMART) model has been modified to improve its efficiency, accuracy, and range of validity. This model is currently being ported to the Beowulf cluster. Several different approaches are being explored to optimize its efficiency in a parallel computing environment. We anticipate that this task will be completed before the end of FY02. We have analyzed the input requirements for the 3 core models and are currently working on defining the optimum interface algorithm to run the coupled model. In addition, work has been started on the geological and biological modeling efforts. We have recently hired a new postdoc and we are awaiting his imminent arrival to start the work on the exogenic models. Spectroscopic information for sulfur-bearing molecules significant for both life and geological processes is being collected. In synergy with our project on biosignatures around stars of different spectral types, we are collecting template stellar spectra and understanding the specific requirements of the chemistry model for different input stellar types.