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The Planetary Habitability Laboratory (PHL) is a research and educational virtual laboratory dedicated to studies of the habitability of Earth, the Solar System, and extrasolar planets. Our main approach is to use the evolution of terrestrial habitability, from paleoclimates to climate change, as a baseline for planetary habitability studies. Our specific objectives are to:
  • Develop habitability metrics and classifications.
  • Trace the evolution of terrestrial habitability.
  • Assess the habitability potential of solar and extrasolar planets.
  • Devise tools and methods for ground, orbital, and remote habitability assessments.
  • Create, provide, and facilitate astrobiology science tools for scientist and educators.
The PHL is working on many research and educational projects. Some of these projects are being done with the help of international collaborators. The LabNotes is a very active section where new ideas and results of many of the projects are explored. The following list shows those projects that are active.

Main Scientific Projects

Habitable Exoplanets Catalog (HEC) — The HEC is the first extensive catalog on the number, diversity, and characteristics of habitable exoplanets in the universe. It uses new developments by the PHL like the Earth Similarity Index (ESI), the Habitable Zones Distance (HZD), classification systems, and comparisons with Earth past and present, to help assess the habitability of exoplanets.

Visible Paleo-Earth (VPE) — The VPE is the first collection of photorealistic visualizations of our planet from space in the last 750 million years. It uses paleogeography and paleoclimate reconstructions combined with NASA satellite imagery to generate our best interpretation of the evolution of the global visual appearance of Earth throughout time.

Scientific Exoplanets Renderer (SER) — SER is a scientific software tool to generate photorealistic visualizations of exoplanets. It uses physical properties from exoplanets and their parent stars to generate possible scenarios for their visual appearance as seem from space. It can be used to interpret and visualize results from General Circulation Models (GCM), reconstruct light-curves, albedo studies, and stellar transit simulations, including moons.

Nearby Stars Catalog (NSC) The NSC is a database of stellar and planetary properties of the nearby stellar system within 10 parsecs (32.6 light years). The database is being used to support statistical studies about the habitability of the solar neighborhood. 

Quantitative Habitability Theory (QH Theory)The purpose of QH Theory is to model the distribution, abundance, and productivity of life. It integrates elements from Habitat Suitability Models (HSM), the Metabolic Theory of Ecology (MTE), Population Dynamics, Macroecology, Biogeography, and Ecophysiology.

Microbial Life Database (MLD) The Microbial Life Database (MLD) is a project to visualize the ecological, physiological and morphological diversity of microbial life. It includes data for nearly 600 well-known prokaryote genera mostly described in Bergey's Manual of Determinative Bacteriology with correction and additions from many other sources.

Other Scientific Projects

Habitability Metrics for Astrobiology (AbSciCon 2012 Special Session) — The NASA Astrobiology Institute will have its Astrobiology Science Conference 2012 next April April 16-20, 2012 in Atlanta, Georgia. As part of this conference we will have a special session on the Development of Quantitative Habitability Assessments for Earth, the Solar System, and Exoplanets (short title Habitability Metrics for Astrobiology). This session is open to contributions from any scientists with an interest in this effort.

Earth Similarity Index (ESI) The ESI, or the "easy scale," is a multiparameter first assessment of Earth-likeness for solar and extrasolar planets as a number between zero (no similarity) and one (identical to Earth). It can be used to prioritize exoplanets observations, perform statistical assessments and develop planetary classifications.

Standard Primary Habitability (SPH)The SPH is a multiparameter measure of habitability for primary producers (i.e. plants) as a number between zero (nominal environment) and one (best environment). It is correlated with the distribution of vegetation and net primary productivity (NPP). The most important application of the SPH is for evaluating the global habitability of Earth (or Earth-like exoplanets) using primary productivity as the standard.

Simulations of Light Curves from Earth-like Exoplanets A computer simulation using photorealistic ray-tracing is being developed to simulate planets with various planetary orbital, rotational and surface configurations including the presence of clouds and seasonal features (i.e. ice cover). The imagery generated as part of the Visible Paleo-Earth will be used to study the different ocean-land-ice variations of Earth in the last 750 million years as base models for Earth as an exoplanet.

EirenespheresThe Eirenespheres enclose the maximum volume in any planetary body with the physical conditions to support at least microbial life. On Earth, they constrain the biosphere and includes parts of the atmosphere, lithosphere, and hydrosphere. The eirenesphere of Mars, Europa, Titan, and Enceladus are in their subsurface, while on Venus is in the upper atmosphere.

Visible Vegetation Index (VVI)The VVI provides a measure of the amount of vegetation or greenness of an image using only information from the visible spectrum. It is an alternative procedure, similar to the NDVI, but in the visible spectrum that measures the amount of green in a region using similarity indices.

HabCat — The Catalog of Nearby Habitable Systems (HabCat) contains a selection of 17,129 candidate host stars for potential habitable exoplanets or "habstars." This page will host HabCat plus some minor future updates in format and content, including data and visualizations. HabCat will be used in other projects of the PHL related to habitable exoplanets.

Educational and Outreach Projects

Exoplanets on Sight (EoS)EoS is a workshop for K-12 students where they learn about exoplanets and create their own exoplanets models with painted ping-pong balls. The students learn to associate planetary features and colors with chemical composition, and land and weather patterns.

Astrobiology Tweets of Prof. Abel Méndez This twitter account provides links to new astrobiology science developments including new results by the PHL.

Universe Explorer Pages — These pages compile from various sources the best interactive online tools to explore the universe, including Mars, the night sky, and the Solar System.
Weather, Earthquakes, and Sky Pages — These experimental pages are a one stop graphical page to learn about current weather, seismic, and sky local conditions in Puerto Rico.