Program: GS-2020B-LP-105

Title:Validation and Characterization of Exoplanets with Gemini HIgh-Resolution Imaging
PI:Steve Howell
Co-I(s): Nic Scott, Rachel Matson, Katie Lester, Johanna Teske, Crystal Gnilka, Elise Furlan, Mark Everett, David Ciardi, Zach Hartman

Abstract

The NASA TESS mission, building on the success of Kepler and K2, has again changed our view of exoplanets. TESS has observed the entire sky in its prime mission, finding candidate exoplanets orbiting bright and nearby stars, and is soon to start its extended mission. Validation and characterization of exoplanets by high-resolution imaging is routinely shown to be absolutely necessary in order to not only prove the planets existence but to allow assignment of a correct radius and density for each exoplanet. The true nature of exoplanet host star binarity, in terms of their orbital period distribution, mass ratio, binary orbit, and even which star the postulated planet orbits are not known a priori but our imaging solves these dilemmas. Given that ~50% of exoplanet host stars are binaries, without high resolution images of the host star a) small planets, especially those in habitable zone orbits, can not be validated and properly characterized and b) any true exoplanet will have, on average, an incorrect radius by a factor of 1.5, that is, the planet will be larger than assumed. We propose to continue our 8-year Gemini community-based speckle imaging program and observe TESS exoplanet host stars as well as some remaining high-value K2 candidates, CHEOPS detections, radial velocity detections with residuals, and repeat observations of a select set for orbits. We will continue to make all of our reduced data public at the Gemini and NASA Exoplanet Archives.

Publications using this program's data