12 research outputs found
KOI-3158: The oldest known system of terrestrial-size planets
The first discoveries of exoplanets around Sun-like stars have fueled efforts to find ever smaller worlds evocative of Earth and other terrestrial planets in the Solar System. While gas-giant planets appear to form preferentially around metal-rich stars, small planets (with radii less than four Earth radii) can form under a wide range of metallicities. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the Universe's history when metals were far less abundant. We report Kepler spacecraft observations of KOI-3158, a metal-poor Sun-like star from the old population of the Galactic thick disk, which hosts five planets with sizes between Mercury and Venus. We used asteroseismology to directly measure a precise age of 11.2 ± 1.0 Gyr for the host star, indicating that KOI-3158 formed when the Universe was less than 20 % of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the Universe's 13.8-billion-year history, providing scope for the existence of ancient life in the Galaxy
Can We Constrain Solar Interior Physics by Studying the Gravity-Mode Asymptotic Signature?
Session2A: MODES − Extracting eigenmode frequencies. Veröffentlichungen der Kommission für Astronomie|Communications in Asteroseismology|Communications in Asteroseismology 157 157|
Solving the mode identification problem in asteroseismology of F stars observed with Kepler
Oscillation mode linewidths of main-sequence and subgiant stars observed by Kepler
International audienc