RIMFAX Ground Penetrating Radar Reveals Dielectric Permittivity and Rock Density of Shallow Martian Subsurface

The Mars 2020 Perseverance Rover is equipped with the RIMFAX ground penetrating radar instrument which has been continuously surveying the shallow subsurface during the rover's journey. Within the first 379 mission days, we identify hyperbolic patterns in the data, which are thought to be caused by objects such as buried boulders or cavities located in the upper 5 m of the subsurface. To obtain the first detailed estimates of radar wave propagation velocity, we match these scatterer-generated patterns with theoretical traveltime hyperbolas, which take into account the refraction at the surface. We employ these estimates to derive the average dielectric permittivity and bulk rock density of the volume above the scatterer source. The parameters compare well with those obtained through orbital radar measurements and those measured by other instruments onboard the Perseverance Rover. Our findings are consistent with a subsurface dominated by solid rock and mafic material.

Automated summary

The Mars 2020 Perseverance Rover's RIMFAX ground penetrating radar has been used to survey the shallow subsurface. The data collected within the first 379 mission days reveal hyperbolic patterns, indicating the presence of buried objects or cavities in the upper 5 meters of the subsurface. By matching these patterns with theoretical traveltime hyperbolas, the researchers obtained detailed estimates of radar wave propagation velocity, average dielectric permittivity, and bulk rock density.