Near-zero cohesion and loose packing of Bennu's near subsurface revealed by spacecraft contact.
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ABSTRACT:
SUBMITTER: Walsh KJ
PROVIDER: S-EPMC9262326 | biostudies-literature | 2022 Jul
REPOSITORIES: biostudies-literature
Publications
Near-zero cohesion and loose packing of Bennu's near subsurface revealed by spacecraft contact.
Walsh Kevin J KJ Ballouz Ronald-Louis RL Jawin Erica R ER Avdellidou Chrysa C Barnouin Olivier S OS Bennett Carina A CA Bierhaus Edward B EB Bos Brent J BJ Cambioni Saverio S Connolly Harold C HC Delbo Marco M DellaGiustina Daniella N DN DeMartini Joseph J Emery Joshua P JP Golish Dathon R DR Haas Patrick C PC Hergenrother Carl W CW Ma Huikang H Michel Patrick P Nolan Michael C MC Olds Ryan R Rozitis Benjamin B Richardson Derek C DC Rizk Bashar B Ryan Andrew J AJ Sánchez Paul P Scheeres Daniel J DJ Schwartz Stephen R SR Selznick Sanford H SH Zhang Yun Y Lauretta Dante S DS
Science advances 20220707 27
When the OSIRIS-REx spacecraft pressed its sample collection mechanism into the surface of Bennu, it provided a direct test of the poorly understood near-subsurface physical properties of rubble-pile asteroids, which consist of rock fragments at rest in microgravity. Here, we find that the forces measured by the spacecraft are best modeled as a granular bed with near-zero cohesion that is half as dense as the bulk asteroid. The low gravity of a small rubble-pile asteroid such as Bennu effectivel ...[more]
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