The fates of Solar system analogues with one additional distant planet

Abstract

The potential existence of a distant planet ("Planet Nine") in the Solar system has prompted a re-think about the evolution of planetary systems. As the Sun transitions from a main sequence star into a white dwarf, Jupiter, Saturn, Uranus and Neptune are currently assumed to survive in expanded but otherwise unchanged orbits. However, a sufficiently-distant and sufficiently-massive extra planet would alter this quiescent end scenario through the combined effects of Solar giant branch mass loss and Galactic tides. Here, I estimate bounds for the mass and orbit of a distant extra planet that would incite future instability in systems with a Sun-like star and giant planets with masses and orbits equivalent to those of Jupiter, Saturn, Uranus and Neptune. I find that this boundary is diffuse and strongly dependent on each of the distant planet's orbital parameters. Nevertheless, I claim that instability occurs more often than not when the planet is as massive as Jupiter and harbours a semimajor axis exceeding about 300 au, or has a mass of a super-Earth and a semimajor axis exceeding about 3000 au. These results hold for orbital pericentres ranging from 100 to at least 400 au. This instability scenario might represent a common occurrence, as potentially evidenced by the ubiquity of metal pollution in white dwarf atmospheres throughout the Galaxy.

Accounting for planet-shaped planetary nebulae

“…Because of sensitivity to unknown tidal interaction parameters, and even to external planets (Veras 2016), studies have reached contradicting conclusions about the fate of the Earth, i.e., whether the Earth will survive engulfment (e.g., Rybicki & Denis 2001), or whether the Sun will engulf the Earth (possibly already during the RGB peak of the sun; Schröder & Connon Smith 2008). Our assumption of a much lower mass loss rate on the giant branches, if holds for the sun, implies that the sun will swallow the Earth.…”

ALMA observations of the nearby AGB star L2 Puppis

“…This directly affects their planetary systems, in the most dramatic way since their formation. Their fate during the final stellar evolution stages has been the subject of several recent works (Veras 2016b;Staff et al 2016;Veras & Wyatt 2012;Schröder & Connon Smith 2008;Villaver & Livio 2007; see also the review by Veras 2016a). However, as AGB star planets are embedded in complex circumstellar envelopes and are vastly outshone by their parent star, the observation of this critical phase presents considerable and yet unsolved challenges.…”

Consequences of a Distant Massive Planet on the Large Semimajor Axis Trans-Neptunian Objects

“…These arguments launched a flurry of discussions and studies on the origins, location, and implications of a ninth planet. The studies have covered formation and capture scenarios Cowan et al 2016;Li & Adams 2016;Mustill et al 2016), constraints on the location, detectability and physical properties of P9 de la Fuente Marcos & de la Fuente Marcos 2016aFienga et al 2016;Fortney et al 2016;Ginzburg et al 2016;Holman & Payne 2016aLinder & Mordasini 2016;Philippov & Chobanu 2016;Toth 2016;Veras 2016), the dynamical implications of P9 in the solar system (de la Fuente Marcos et al 2016c;Lawler et al 2016), P9 producing inclined TNOs (Batygin & Brown 2016b), resonances and P9 (Beust 2016;Malhotra et al 2016), a dark matter P9 (Sivaram et al 2016), and impacts of P9 on the Sun's obliquity (Bailey et al 2016;Lai 2016).…”