학술논문
Internal rubble properties of asteroid (101955) Bennu
Document Type
Working Paper
Author
Tricarico, P.; Scheeres, D. J.; French, A. S.; McMahon, J. W.; Brack, D. N.; Leonard, J. M.; Antreasian, P.; Chesley, S. R.; Farnocchia, D.; Takahashi, Y.; Mazarico, E. M.; Rowlands, D.; Highsmith, D.; Getzandanner, K.; Moreau, M.; Johnson, C. L.; Philpott, L.; Bierhaus, E. B.; Walsh, K. J.; Barnouin, O. S.; Palmer, E. E.; Weirich, J. R.; Gaskell, R. W.; Daly, M. G.; Seabrook, J. A.; Nolan, M. C.; Lauretta, D. S.
Source
Subject
Language
Abstract
Exploration of asteroid (101955) Bennu by the OSIRIS-REx mission has provided an in-depth look at this rubble-pile near-Earth asteroid. In particular, the measured gravity field and the detailed shape model of Bennu indicate significant heterogeneities in its interior structure, compatible with a lower density at its center. Here we combine gravity inversion methods with a statistical rubble-pile model to determine the density and size-frequency distribution (SFD) index of the rubble that constitutes Bennu. The best-fitting models indicate that the SFD of the interior is consistent with that observed on the surface, with a cumulative SFD index of approximately $-2.9$. The rubble bulk density is approximately $1.35$ g/cm$^3$, corresponding to a $12$% macro-porosity. We find the largest rubble particle to be approximately $145$ m, whereas the largest void is approximately $10$ m.
Comment: 14 pages, 5 figures, accepted to Icarus
Comment: 14 pages, 5 figures, accepted to Icarus