Skip to main content

Dynamical constraints on the origin of hot and warm Jupiters with close friends


Image: Artist's concept of a "hot Jupiter" - Credit: NASA/JPL-Caltech

Gas giants orbiting their host star within the ice line are thought to have migrated to their current locations from farther out.

In a recent paper (Antonini et al 2016) the authors consider the origin and dynamical evolution of observed Jupiters, focusing on hot and warm Jupiters with outer friends. They show that the majority of the observed Jupiter pairs (twenty out of twenty-four) will be dynamically unstable if the inner planet was placed at >~1AU distance from the stellar host.

This finding is at odds with formation theories that invoke the migration of such planets from semi-major axes >~1AU due to secular dynamical processes (e.g., secular chaos, Lidov-Kozai oscillations) coupled with tidal dissipation. In fact, the results of N-body integrations show that the evolution of dynamically unstable systems does not lead to tidal migration but rather to planet ejections and collisions with the host star.

This and other arguments lead the authors to suggest that most of the observed planets with a companion could not have been transported from further out through secular migration processes. More generally, by using a combination of numerical and analytic techniques they show that the high-e Lidov-Kozai migration scenario can only account for less than 10% of all gas giants observed between 0.1-1 AU.

Simulations of multi-planet systems support this result. Their study indicates that rather than starting on highly eccentric orbits with orbital periods above one year, these "warm" Jupiters are more likely to have reached the region where they are observed today without having experienced significant tidal dissipation.

  • Antonini et al 2016 (preprint) - Dynamical constraints on the origin of hot and warm Jupiters with close friends - (arXiv)

Etichette:

Comments

Post a Comment

Popular posts from this blog

A UNIVERSE WITHOUT A CENTER?

Image Credit: Eugenio Bianchi, Carlo Rovelli & Rocky Kolb. According to the standard theories of cosmology, there is no center of the universe. In a conventional explosion, material expand out from a central point and the instinct suggests that with the Big Bang happened something similar. But the Big Bang was not an explosion like that at all: it was an explosion of space, not an explosion in space . The Big Bang happened everywhere in the Universe.
Post a Comment
Read more

UNIVERSE IS FINITE OR INFINITE?

Art by Moonrunner Design   At present there is no answer to this question. However I will try to list the hypothesys currently on the table with related issues.
Post a Comment
Read more

New research looks at how ‘cosmic web’ of filaments alters star formation in galaxies

Cosmic Web. Credit: NASA Astronomer Gregory Rudnick sees the universe crisscrossed by something like an interstellar superhighway system. Filaments — the strands of aggregated matter that stretch millions of light years across the universe to connect galaxy clusters — are the freeways. “Galaxies will flow along filaments from less dense parts of the universe to more dense parts of the universe, kind of like cars flowing down a highway to the big city. In this case, they are going toward big clusters, being pulled by the gravity of those large concentrations of matter,” he said. “I’m interested in how galaxies are affected by the regions in which they live,” Rudnick said. “Filaments are the first place where galaxies come into contact with higher density regions of the universe. If a galaxy in a ‘rural’ part of the universe enters a dense part, I want to know how its properties change — for example, does it change the number of stars it forms, or does its shape get altered? Us...
Post a Comment
Read more