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TL;DR

This paper proposes that the Large Magellanic Cloud is on its second orbit around the Milky Way, supported by N-body simulations, which explains satellite distributions and the Magellanic system's history.

Contribution

It introduces a second-passage orbital scenario for the LMC, aligning with observations and explaining satellite associations and the plane of satellites.

Findings

Second-passage scenario fits observational constraints

LMC could have brought 4-6 additional satellites

Classical dwarfs may have once belonged to the Magellanic system

Abstract

We propose a scenario in which the Large Magellanic Cloud (LMC) is on its second passage around the Milky Way. Using a series of tailored N-body simulations, we demonstrate that such orbits are consistent with current observational constraints on the mass distribution and relative velocity of both galaxies. The previous pericentre passage of the LMC could have occurred 5-10 Gyr ago at a distance >~100 kpc, large enough to retain its current population of satellites. The perturbations of the Milky Way halo induced by the LMC look nearly identical to the first-passage scenario, however, the distribution of LMC debris is considerably broader in the second-passage model. We examine the likelihood of current and past association with the Magellanic system for dwarf galaxies in the Local Group, and find that in addition to 10-11 current LMC satellites, it could have brought a further 4-6 galaxies that have been lost after the first pericentre passage. In particular, four of the classical dwarfs - Carina, Draco, Fornax and Ursa Minor - each have a ~50% probability of once belonging to the Magellanic system, thus providing a possible explanation for the ``plane of satellites'' conundrum.