Volatile-rich Earth-Mass Planets in the Habitable Zone
Abstract
A small planet is not necessarily a terrestrial planet. Planets that form beyond the snow line with too little mass to seed rapid gas accretion (<~10 M⊕) should be rich in volatile ices like H2O and NH3. Some of these planets should migrate inward by interacting with a circumstellar disk or with other planets. Such objects can retain their volatiles for billions of years or longer at ~1 AU as their thick steam atmospheres undergo slow hydrodynamic escape. These objects could appear in future surveys for extrasolar Earth analogs.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 2003
- DOI:
- 10.1086/378397
- arXiv:
- arXiv:astro-ph/0303186
- Bibcode:
- 2003ApJ...596L.105K
- Keywords:
-
- Astrobiology;
- Stars: Planetary Systems;
- Astrophysics
- E-Print:
- 12 pages, including 1 figure. To appear in ApJ letters October 10, 2003