Origin of Mars's moons by disruptive partial capture of an asteroid
arXiv:2407.15936 · doi:10.1016/j.icarus.2024.116337
Abstract
The origin of Mars's small moons, Phobos and Deimos, remains unknown. They are typically thought either to be captured asteroids or to have accreted from a debris disk produced by a giant impact. Here, we present an alternative scenario wherein fragments of a tidally disrupted asteroid are captured and evolve into a collisional proto-satellite disk. We simulate the initial disruption and the fragments' subsequent orbital evolution. We find that tens of percent of an unbound asteroid's mass can be captured and survive beyond collisional timescales, across a broad range of periapsis distances, speeds, masses, spins, and orientations in the Sun--Mars frame. Furthermore, more than one percent of the asteroid's mass could evolve to circularise in the moons' accretion region. This implies a lower mass requirement for the parent body than that for a giant impact, which could increase the likelihood of this route to forming a proto-satellite disk that, unlike direct capture, could also naturally explain the moons' orbits. These three formation scenarios each imply different properties of Mars's moons to be tested by upcoming spacecraft missions.
Published in Icarus. 32 pages, 19 figures, 3 tables
References in corpus (19)
- Formation of Phobos and Deimos via a Giant Impact
- SWIFT: A modern highly-parallel gravity and smoothed particle hydrodynamics solver for astrophysical and cosmological applications
- On the Impact Origin of Phobos and Deimos I: Thermodynamic and Physical Aspects
- Impact bombardment chronology of the terrestrial planets from 4.5 Ga to 3.5 Ga
- Ring Formation around Giant Planets by Tidal Disruption of a Single Passing Large Kuiper Belt Object
- Reconstruction of asteroid spin states from Gaia DR3 photometry
- Transport of impact ejecta from Mars to its moons as a means to reveal Martian history
- Immediate origin of the Moon as a post-impact satellite
- A recent impact origin of Saturn's rings and mid-sized moons
- On the Impact Origin of Phobos and Deimos II: True Polar Wander and Disk Evolution
- Dynamical Evolution of the Earth-Moon Progenitors - Whence Theia?
- Temporary Capture of Asteroids by an Eccentric Planet
- Has the impact flux of small and large asteroids varied through time on Mars, the Earth and the Moon?
- Reconceiling the orbital and physical properties of the martian moons
- Exploring the recycling model of Phobos formation: rubble-pile satellites
- Evidence for a Past Martian Ring from the Orbital Inclination of Deimos
- Phobos photometric properties from Mars Express HRSC observations
- Giga-Year Dynamical Evolution of Particles Around Mars
- Rotation periods and shape asphericity in asteroid families based on TESS S1-S13 observations