Implantation of Martian materials in the inner solar system by a mega impact on Mars

TL;DR

This study uses hydrodynamic simulations to show that a mega impact on Mars could eject and distribute Martian materials, including mantle debris, across the inner solar system, explaining their presence in asteroids and on Earth.

Contribution

It provides the first detailed simulation-based analysis of how a mega impact on Mars can implant Martian materials into the inner solar system, including asteroid belts and Earth.

Findings

Approximately 1% of Mars' mass is ejected as debris.

Debris includes Martian crust/mantle and impactor materials.

Some debris can reach Earth and form Martian Trojans.

Abstract

Observations and meteorites indicate that the Martian materials are enigmatically distributed within the inner solar system. A mega impact on Mars creating a Martian hemispheric dichotomy and the Martian moons can potentially eject Martian materials. A recent work has shown that the mega-impact-induced debris is potentially captured as the Martian Trojans and implanted in the asteroid belt. However, the amount, distribution, and composition of the debris has not been studied. Here, using hydrodynamic simulations, we report that a large amount of debris ($\sim 1\%$ of Mars' mass), including Martian crust/mantle and the impactor's materials ($\sim 20:80$), are ejected by a dichotomy-forming impact, and distributed between $\sim 0.5-3.0$ astronomical units. Our result indicates that unmelted Martian mantle debris ($\sim 0.02\%$ of Mars' mass) can be the source of Martian Trojans, olivine-rich asteroids in the Hungarian region and the main asteroid belt, and some of which even hit early Earth. A mega impact can naturally implant Martian mantle materials within the inner solar system.