Hot Jupiters from secular planet-planet interactions

Smadar Naoz*, Will M. Farr, Yoram Lithwick, Frederic A. Rasio, Jean Teyssandier

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

343 Scopus citations


About 25 per cent of 'hot Jupiters' (extrasolar Jovian-mass planets with close-in orbits) are actually orbiting counter to the spin direction of the star. Perturbations from a distant binary star companion can produce high inclinations, but cannot explain orbits that are retrograde with respect to the total angular momentum of the system. Such orbits in a stellar context can be produced through secular (that is, long term) perturbations in hierarchical triple-star systems. Here we report a similar analysis of planetary bodies, including both octupole-order effects and tidal friction, and find that we can produce hot Jupiters in orbits that are retrograde with respect to the total angular momentum. With distant stellar mass perturbers, such an outcome is not possible. With planetary perturbers, the inner orbit's angular momentum component parallel to the total angular momentum need not be constant. In fact, as we show here, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter.

Original languageEnglish (US)
Pages (from-to)187-189
Number of pages3
Issue number7346
StatePublished - May 12 2011

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Hot Jupiters from secular planet-planet interactions'. Together they form a unique fingerprint.

Cite this