Collaborative Research: Masses and architectures of (potentially habitable) exoplanet systems

University Of Washington, Seattle WA

Investigators

Abstract

Systems of many planets around other stars where the planets pass, or transit, across their stars can become probes of the masses and sizes of these planets. Transits that show changes in the timing of their passages, or transit timing variations (TTVs), provide information about both planetary masses and planetary radii. The investigators will study the masses and radii and how they are related for these multiple-planet transiting systems for ~100 low-mass exoplanets, found by the Kepler Space Telescope, with added measurements from other ground-based and space-based telescopes. The results of the modeling and observations could be used to place limits on planet formation and evolution, and plan for future spacecraft studies of zones where we expect to find planets that could have life. The computer programs developed as part of this work will be available to other scientists. This research serves the national interest by advancing our abilities to find planets around other stars that could have life. Both principal investigators are involved with education and outreach programs, emphasizing the Pre-Major in Astronomy Program (Pre-MAP) at University of Washington, and inner-city high school students from South Chicago participating in research through the Space Explorers program. Transit timing variations (TTVs) are sensitive to both planetary masses and planetary radii. This study will probe the mass-radius relation for multi-planet transiting systems for a large sample of ~100 low-mass exoplanets, found by the spaceborne telescope Kepler, and supplemented by ground-based measurements, Kepler's K2 mission, and Spitzer Space Telescope. The investigators will apply the technique of TTVs to existing, future, and simulated datasets using new codes they have developed for transit, TTV, and composition modeling. The goals are to continue development of transit timing analysis and planetary composition analysis tools; to extend the monitoring of Kepler planets beyond the Kepler dataset; to carry out mass measurements of multi-planet systems, and to constrain the orbital parameters and the presence of additional planets using transit timing analysis; to constrain the planets' bulk densities and interior compositions, to carry out dynamical analyses of these planetary systems, and to carry out statistical analyses of the properties of these systems; and, to simulate future James Webb Space Telescope observations of potentially rocky exoplanets in or near the habitable zone in order to probe the mass-radius relation for these low-mass, low-insolation planets. The resulting data could be used to place constraints upon planet formation and evolution, and plan for future spacecraft studies of habitable-zone planets. The analysis codes developed under this proposal will be freely available to the scientific community. Both principal investigators are involved with education and outreach programs, emphasizing the Pre-Major in Astronomy Program (Pre-MAP) at University of Washington, and inner-city high school students from South Chicago participating in research through the Space Explorers program.