Jumping Jupiter can explain Mercury's orbit

TL;DR

This paper demonstrates that the jumping Jupiter model, incorporating relativistic effects, can explain Mercury's current eccentricity and inclination by simulating the orbital evolution during giant planet migration.

Contribution

It shows that specific instability models within the jumping Jupiter framework can reproduce Mercury's orbit, highlighting the importance of relativistic effects.

Findings

Relativistic effects are crucial for matching Mercury's orbit.

Orbital excitation results from rapid changes in Jupiter's perihelion precession.

Uranus's nodal regression influences Mercury's inclination.

Abstract

The orbit of Mercury has large values of eccentricity and inclination that cannot be easily explained if this planet formed on a circular and coplanar orbit. Here, we study the evolution of Mercury's orbit during the instability related to the migration of the giant planets in the framework of the jumping Jupiter model. We found that some instability models are able to produce the correct values of Mercury's eccentricity and inclination, provided that relativistic effects are included in the precession of Mercury's perihelion. The orbital excitation is driven by the fast change of the normal oscillation modes of the system corresponding to the perihelion precession of Jupiter (for the eccentricity), and the nodal regression of Uranus (for the inclination).