On the origins of eccentric close-in planets

Soko Matsumura, Genya Takeda, Fred A. Rasio

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


Strong tidal interaction with the central star can circularize the orbits of close-in planets. With the standard tidal quality factor Q of our solar system, estimated circularization timescales for close-in extrasolar planets are typically shorter than the age of the host stars. While most extrasolar planets with orbital radii α ≲ 0.1 AU indeed have circular orbits, some close-in planets with substantial orbital eccentricities have recently been discovered. This new class of eccentric close-in planets implies that either their tidal Q factor is considerably higher, or circularization is prevented by an external perturbation. Here we constrain the tidal Q factor for transiting extrasolar planets by comparing their circularization times with accurately determined stellar ages. Using estimated secular perturbation timescales, we also provide constraints on the properties of hypothetical second planets exterior to the known eccentric close-in planets.

Original languageEnglish (US)
Pages (from-to)189-195
Number of pages7
JournalProceedings of the International Astronomical Union
Issue numberS253
StatePublished - May 2008

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Astronomy and Astrophysics
  • Nutrition and Dietetics
  • Public Health, Environmental and Occupational Health
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'On the origins of eccentric close-in planets'. Together they form a unique fingerprint.

Cite this