1. Hemispherical differences in the shape and topography of asteroid (101955) Bennu
- Author
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James H. Roberts, Benjamin Rozitis, Yun Zhang, E. B. Bierhaus, J. A. Seabrook, K. Getzandanner, Michael Daly, D. N. DellaGuistina, Clive Dickinson, P. Michel, Mark E. Perry, J. R. Weirich, Lydia C. Philpott, R. T. Daly, Robert Gaskell, Hannah C.M. Susorney, J. Geeraert, Andrew Ryan, Eric Palmer, G. Cunningham, Charles Brunet, M. Al Asad, Jason M. Leonard, M. C. Nolan, R. L. Ballouz, H. L. Enos, Olivier S. Barnouin, Dante S. Lauretta, D. Gaudreau, Coralie D. Adam, T. Haltigin, Bashar Rizk, Erwan Mazarico, Gregory A. Neumann, Catherine L. Johnson, Erica Jawin, Kevin J. Walsh, Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Southwest Research Institute [Boulder] (SwRI), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lunar and Planetary Laboratory [Tucson] (LPL), and University of Arizona
- Subjects
business.product_category ,010504 meteorology & atmospheric sciences ,Longitudinal ridges ,[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] ,01 natural sciences ,0103 physical sciences ,Asymmetric distribution ,Altimeter ,Digital elevation model ,010303 astronomy & astrophysics ,Geomorphology ,Southern Hemisphere ,Research Articles ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,Multidisciplinary ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Northern Hemisphere ,SciAdv r-articles ,Wedge (mechanical device) ,Asteroid ,[SDU]Sciences of the Universe [physics] ,business ,Space Sciences ,Geology ,Research Article - Abstract
A lidar model of asteroid (101955) Bennu has a north-south asymmetry in shape and evidence of an early partial disruption., We investigate the shape of near-Earth asteroid (101955) Bennu by constructing a high-resolution (20 cm) global digital terrain model from laser altimeter data. By modeling the northern and southern hemispheres separately, we find that longitudinal ridges previously identified in the north extend into the south but are obscured there by surface material. In the south, more numerous large boulders effectively retain surface materials and imply a higher average strength at depth to support them. The north has fewer large boulders and more evidence of boulder dynamics (toppling and downslope movement) and surface flow. These factors result in Bennu’s southern hemisphere being rounder and smoother, whereas its northern hemisphere has higher slopes and a less regular shape. We infer an originally asymmetric distribution of large boulders followed by a partial disruption, leading to wedge formation in Bennu’s history.
- Published
- 2020
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