Astrobiology: Life in the Universe

NASA Astrobiology Institute (NAI)


  1. Planet Formation and Dynamical Modeling

    Project Investigators: Sean Raymond, Monika Kress, John Scalo, Rory Barnes, Vikki Meadows

    Astrobiology Roadmap Objectives:

    Project Progress

    We have extended models of terrestrial planet formation to new domains such as around low-mass stars and binary stars. We are developing a new model for the origin of carbon on the Earth and other habitable planets, based on studies of meteoritics, protoplanetary disk structure, and planetary accretion. We have also studied the long-term tidal-orbital evolution of habitable zone planets around low-mass stars, and found that in some cases planets may form in the habitable zone but evolve in to hotter orbits because of tidal effects. We have studied the formation of close-in terrestrial planets (e.g., “super-Earths”) and have shown that with high-precision transit and radial velocity information it may be possible to uniquely determine the formation mechanism. We have studied the dynamics of extra-solar planetary systems – in 2007 we were the first to successfully predict the mass and orbit of an exoplanet. We continue to develop new models for the formation and evolution of planets both in our own solar system and around other stars.

    Mission Involvement

    Space Interferometry Mission (SIM)
    Raymond and Barnes are involved in a project to test SIM's ability to find planets around other starts. Raymond is involved in generating artificial planetary systems. These systems are then turned into artificial observations by a team led by Wes Traub (JPL). Finally, a third set of teams (including Barnes) attempts to reconstitute the input planetary systems from the artificial observations.
    Kepler
    Raymond and Barnes are both involved in modeling the formation, tidal and dynamical evolution of planetary systems around other stars. Some of the ideas that have been developed will be directly tested by Kepler. In particular, a recent paper by Raymond, Barnes & Mandell (2008) shows that, in some cases, a combination of transit measurements and radial velocity information can tell apart different formation models for close-in terrestrial planets.
    Terrestrial Planet Finder / New Worlds Observer
    Formation models such as those generated by Raymond, Kress, Scalo, Meadows and Barnes will be tested and constrained by upcoming missions like TPF or New Worlds Observer.