KOI-3158: The oldest known system of terrestrial-size planets
- Creators
- Campante, T. L.
- Swift, J. J.
- Riddle, R.
Abstract
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.
Additional Information
© 2015 Owned by the authors, published by EDP Sciences. This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Published online: 23 September 2015.Attached Files
Published - epjconf_sphr2014_02004.pdf
Submitted - 1501.07869v1.pdf
Files
Name | Size | Download all |
---|---|---|
md5:ac0b70c2e8d9f6d2e88e76840ae029b9
|
1.3 MB | Preview Download |
md5:1b8c95d3560c36c9191e5d21d5cc08eb
|
1.9 MB | Preview Download |
Additional details
- Eprint ID
- 66402
- Resolver ID
- CaltechAUTHORS:20160422-094108983
- Created
-
2016-04-22Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field