Single impact explains Deimos's shape and smooth surface
New simulations suggest a single oblique impact shaped Deimos, Mars's smaller moon, creating its distinctive depression and smooth regolith-covered surface.
New research published in Nature Astronomy suggests that a single oblique impact could have shaped Deimos, the smaller of Mars's two moons, explaining its unique surface features and internal structure. The study, led by Raducan et al., uses computer simulations to show that a collision likely created the moon’s south-polar depression and distributed a layer of regolith across its surface.
The findings align with recent observations of Deimos’s shape and geology, which indicate a surface composed of loose, fragmented material rather than a solid body. The simulations also suggest that the moon’s interior may resemble the structure of certain asteroids, such as Ryugu, which was found to have a low-strength rubble-pile composition.
The research builds on prior studies of Mars's moons, including a 2021 review by Ramsley and Head that outlined competing theories on their formation. It also references a 2023 paper by Ernst et al. that provided high-resolution shape models of Deimos and Phobos, which were used in the pre-impact reconstruction of Deimos.
The study is relevant to upcoming space missions, such as the Japanese MMX mission, which aims to collect samples from Phobos and study the formation processes of Mars's moons. These missions could provide further evidence to test the impact hypothesis and deepen our understanding of the early solar system.
This study provides a concrete mechanism for how a single impact could have sculpted Deimos, offering insight into the geological evolution of small celestial bodies. The findings suggest that impact processes are fundamental to shaping planetary satellites, a process that may be critical for understanding the formation of Mars’s moons and, more broadly, the dynamics of small bodies in the solar system. As humanity looks to establish a presence on Mars, understanding the history and structure of its moons can inform future exploration and resource utilization. This research supports the vision of a multi-planetary civilization by deepening our knowledge of the solar system’s natural satellites, laying the groundwork for future interplanetary expansion.
Edited by the news editor with AI from the original report — please refer to the original source.