Revised estimates of the frequency of Earth-like planets in the Kepler field
arXiv:1811.08249
Abstract
The search for Earth-like planets around Sun-like stars and the evaluation of their occurrence rate is a major topic of research for the exoplanetary community. Two key characteristics in defining a planet as 'Earth-like' are having a radius between 1 and 1.75 times the Earth's radius and orbiting inside the host star's habitable zone; the measurement of the planet's radius and related error is however possible only via transit observations and is highly dependent on the precision of the host star's radius. A major improvement in the determination of stellar radius is represented by the unprecedented precision on parallax measurements provided by the Gaia astrometry satellite. We present a new estimate of the frequency of Earth-sized planets orbiting inside the host stars's habitable zones, obtained using Gaia measurements of parallax for solar-type stars hosting validated planets in the Kepler field as input for reassessing the values of planetary radius and incident stellar flux. This updated occurrence rate can usefully inform future observational efforts searching for Earth-like system in the Sun backyard using a variety of techniques such as the spectrograph ESPRESSO, the space observatory PLATO and the proposed astrometric satellite Theia.
arXiv comment7 pages, 2 figures, 1 table. To appear in the Proceedings of IAU Symposium 348: 21st Century Astrometry: crossing the Dark and Habitable frontiers
References in corpus (3)
Cited by in corpus (4)
- Accounting for Multiplicity in Calculating Eta Earth
- The Pan-Pacific Planet Search. VIII. Complete results and the occurrence rate of planets around low-luminosity giants
- Four Jovian planets around low-luminosity giant stars observed by the EXPRESS and PPPS
- New models of reflection spectra for terrestrial exoplanets: Present and prebiotic Earth orbiting around stars of different spectral types