Surface refreshing of Martian moon Phobos by orbital eccentricity-driven grain motion

  title={Surface refreshing of Martian moon Phobos by orbital eccentricity-driven grain motion},
  author={R.-L. Ballouz and Nicola Baresi and Sarah T. Crites and Yasuhiro Kawakatsu and Masaki Fujimoto},
  journal={Nature Geoscience},
The surface of the Martian moon Phobos exhibits two distinct geologic units, red and blue, characterized by their spectral slopes. The provenance of these units is uncertain yet crucial to understanding the origin of the Martian moon and its interaction with the space environment. Here we present a combination of dynamical analyses and numerical simulations of particle dynamics to show that periodic variations in dynamic slopes, driven by orbital eccentricity, can cause surface grain motion… 

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