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Project Reports

• The Virtual Planetary Laboratory – The Life Modules – Photosynthesis

  Photosynthesis provides the foundation for nearly all life on our planet and produces unique life signs — atmospheric oxygen and pigment colors — that are detectable from space at the global scale. This project seeks to determine the adapative rules for why photosynthetic pigments absorb particular wavelengths of light, and to quantify what is the long wavelength limit for oxygenic and also anoxygenic photosynthesis. This work will allow us to predict the plausible spectral properties and detectable properties of photosynthesis on other planets, especially those orbiting M stars, where longer wavelengths of light dominate the planetary surface radiation.

  ROADMAP OBJECTIVES: 5.1 6.1 6.2 7.2

• Stromatolites in the Desert: Analogs to Other Worlds

  Field work at Cuatro Ciénegas, Mexico has focused on understanding unique
  structures called microbialites. These are colonies of bacteria that have
  been encased by minerals that have precipated out of the water surrounding
  them. This process have been going on for 2 and a half billion years on
  earth. The work we are doing is using experiments to see how the environment
  can affect the genes in these bacteria to create the microbialites. We do
  this to improve our understanding of how they utilize two very important atoms, carbon and nitrogen. By studying these Earth bacteria we can better understand how microbialites interact with their environemnt, and whether or not microbialites might exist and be detectable in extrasolar environments.

  ROADMAP OBJECTIVES: 5.1 5.2 5.3

• Planet Formation and Dynamical Modeling

  In this task, we use computer models of the formation of terrestrial planets and the chemistry in the protoplanetary disk to better understand how carbon, the backbone of life processes, becomes incorporated into
  forming planets. Our planet formation models are also being used to understand planet formation around low-mass stars and binary stars, and how tidal interactions between planet and star can cause a planet’s orbit to evolve
  over time, potentionally taking it into, or out of, the habitable zone.

  ROADMAP OBJECTIVES: 1.1 3.1 4.3

• Modeling Early Earth Environments

  In this project, scientists from different disciplines model the conditions likely to have been found on the Early Earth, prior to 2.3 billion years ago. Specific areas of research include understanding the gases, many biologically produced, and mechanisms that controlled early Earth’s surface temperature, the nature of hazes that shielded the planetary surface from UV and may be responsible for signatures in sulfur isotopes that were left in the rock record, the chemical nature of the Earth’s environment during and after a planet-wide glaciation (a “Snowball event”), the evolution of planetary atmospheres over time due to loss of atmosphere to space, and the use of iron isotopes as a tracer of the oxidative state of the Earth’s ocean over time.

  ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 4.2 5.1 5.2 5.3 6.1 7.2

• Effects of Stellar Flares on Atmospheres of Habitable Planets

  Stellar flares, sudden energy bursts from a star, produce a cascade of particles and radiation that can affect that can affect the atmospheres of orbiting planets. Our research is focused on understanding how the atmospheric chemistry of a planet is affected by flares. We want to know if flares can modify the concentrations of compounds that are produced by life and released to the planetary atmosphere and if the ultraviolet radiation during a flare can reach the planetary surface and damage the possible organisms on that planet.

  ROADMAP OBJECTIVES: 1.1 4.3 7.2

• Astronomical Observations of Terrestrial Planet Atmospheres

  In this project we use telescopes and spectrometers on the Earth to study the atmospheres of Venus and Mars to learn more about the current conditions and history of water on these planets. This work also supports ongoing space-based observations of these worlds.

  ROADMAP OBJECTIVES: 1.2 7.2

• VPL Model Interfaces and the Community Tool

  The Virtual Planetary Laboratory’s primary mission is to support NASA’s ongoing planet-finding efforts by building computer simulated Earth-sized worlds to discover the likely range of environments for planets around other stars. To that end, we are developing web-based community tools that allow researchers to collaborate on planetary climate models. These tools combine models and data that help predict the observable properties of planets orbiting other stars.

  ROADMAP OBJECTIVES: 1.1 4.1 7.2

• Planetary Habitability

  In this research project, members of the VPL team explore different aspects of planetary habitability, and the detectability of habitability and life, using a combination of theoretical models, astronomical observations and Earth-based field work.

  ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 4.1 5.3 6.1 7.2

• Earth as an Extrasolar Planet

  In this project we are comparing an existing model of the Earth with images and spectra of the Earth obtained from a distance spacecraft. The VPL Earth model uses Earth observing satellite data including atmospheric conditions and cloud cover to simulate both images and spectra of the Earth on a given day of observation. The comparision between the model and data will help us improve our model, and will also provide information on how detectable some of the Earth’s environmental characteristics would be to an observer in another planetary system.

  ROADMAP OBJECTIVES: 1.2 7.2

• VPL Climate and Radiative Transfer Models

  This project develops models of planetary atmospheres and surface temperature to allow us to model extra solar terrestrial planetary environments and to understand what they would look like to distant observers.

  ROADMAP OBJECTIVES: 1.1 1.2

• Planetary Surface and Interior Models and Super Earths

  In this task we are developing and using models of a terrestrial planet’s surface and interior to understand
  the evolution of planetary environments. These models allow us to understand how interactions between the
  planetary surface and interior, and life, affect a planet’s atmosphere. New models are also exploring the possible habitability of “super-Earths”, rocky planets that have been found around other stars that can be up to 10 times more massive than our own Earth.

  ROADMAP OBJECTIVES: 1.1 1.2 4.1 5.2 6.1 7.2