Episodes of particle ejection from the surface of the active asteroid (101955) Bennu

@article{Lauretta2019EpisodesOP,
  title={Episodes of particle ejection from the surface of the active asteroid (101955) Bennu},
  author={Dante S. Lauretta and Carl W. Hergenrother and Steven R. Chesley and Jason M. Leonard and John Y. Pelgrift and Coralie D. Adam and Manar M. Al Asad and Peter G. Antreasian and R.‐L. Ballouz and Kris J. Becker and Carina A. Bennett and Brent J. Bos and William F. Bottke and Maja Brozovi{\'c} and Humberto Campins and Harold C. Connolly and Michael G. Daly and Alex B. Davis and Julia de Le{\'o}n and Daniella N. DellaGiustina and C. Y. Drouet d’Aubigny and Jason P. Dworkin and Joshua P. Emery and Davide Farnocchia and Daniel P. Glavin and Dathon R. Golish and Christine M Hartzell and Robert A. Jacobson and Erica R. Jawin and Peter Jenniskens and John N. Kidd and E. J. Lessac-Chenen and J.‐Y. Li and Guy Libourel and Javier Licandro and Andrew J. Liounis and C. K. Maleszewski and C. Manzoni and B. H. May and Leilah McCarthy and Jay W. McMahon and Patrick Michel and Jamie L. Molaro and Michael C. Moreau and Derek S. Nelson and W. M. Owen and Bashar Rizk and H. L. Roper and Benjamin Rozitis and Eric M. Sahr and Daniel J. Scheeres and Jeffrey A. Seabrook and S. H. Selznick and Y. Takahashi and Florian Thuillet and Pasquale Tricarico and David Vokrouhlick{\'y} and Catherine W. V. Wolner},
  journal={Science},
  year={2019},
  volume={366}
}
Bennu ejects material from its surface Most asteroids appear inert, but remote observations show that a small number experience mass loss from their surfaces. Lauretta and Hergenrother et al. describe close-range observations of mass loss on the near-Earth asteroid Bennu (see the Perspective by Agarwal). Shortly after arriving at Bennu, navigation cameras on the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security—Regolith Explorer) spacecraft detected objects 1… 
Introduction to the Special Issue: Exploration of the Activity of Asteroid (101955) Bennu
TLDR
Of the potential mechanisms behind this activity that were investigated in focused studies, meteoroid impacts, thermal fracturing, and ricochet—but not water ice sublimation—were found to be consistent with observations, suggesting that many near‐Earth asteroids may exhibit activity that has gone unnoticed thus far.
Meteoroid Impacts as a Source of Bennu's Particle Ejection Events
TLDR
It is found that 7,000‐J impacts on Bennu occur with a biweekly cadence near perihelion, with a preference to strike in the late afternoon (~6 pm local time), which matches observations.
Close-up view of an active asteroid
TLDR
Centimeter-sized debris was found ejected from the surface of the likely ice-free asteroid 101955 Bennu in images taken by NASA's OSIRIS-REx spacecraft, showing that asteroids are far from being inert bodies.
Photometry of Particles Ejected From Active Asteroid (101955) Bennu
Near‐Earth asteroid (101955) Bennu is an active asteroid experiencing mass loss in the form of ejection events emitting up to hundreds of millimeter‐ to centimeter‐scale particles. The close
Dynamical Evolution of Simulated Particles Ejected From Asteroid Bennu
In early 2019, the OSIRIS‐REx spacecraft discovered small particles being ejected from the surface of the near‐Earth asteroid Bennu.sww Although they were seen to be ejected at slow speeds, on the
Reconstruction of Bennu Particle Events From Sparse Data
TLDR
This newly developed technique offers the capacity to meaningfully constrain the properties of particle ejection events from limited data and comparison with higher‐fidelity orbit determination solutions for the events with sufficient observations demonstrates the validity of this approach.
Widespread carbon-bearing materials on near-Earth asteroid (101955) Bennu
TLDR
The OSIRIS-REx results constrain Bennu's evolution and provide context for the sample collected in October 2020, as well as finding evidence for organic and carbonate materials that are widely distributed across the surface but are most concentrated on individual boulders.
Variations in color and reflectance on the surface of asteroid (101955) Bennu
TLDR
Maps of color and albedo on asteroid Bennu indicate complex evolution of its surface due to space weathering, and constrain Bennu's evolution and provide context for the sample collected in October 2020.
Bright carbonate veins on asteroid (101955) Bennu: Implications for aqueous alteration history
TLDR
Global spectral observations by the OSIRIS-REx spacecraft have shown that carbon-bearing materials, including organics and/or carbonates, are widespread on the surface of near-Earth asteroid (101955) Bennu.
Global Patterns of Recent Mass Movement on Asteroid (101955) Bennu
The exploration of near‐Earth asteroids has revealed dynamic surfaces characterized by mobile, unconsolidated material that responds to local geophysical gradients, resulting in distinct morphologies
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