Premium
Dynamical Evolution of Simulated Particles Ejected From Asteroid Bennu
Author(s) -
McMahon Jay W.,
Scheeres Daniel J.,
Chesley Steven R.,
French Andrew,
Brack Daniel,
Farnocchia Davide,
Takahashi Yu,
Rozitis Benjamin,
Tricarico Pasquale,
Mazarico Erwan,
Bierhaus Beau,
Emery Joshua P.,
Hergenrother Carl W.,
Lauretta Dante S.
Publication year - 2020
Publication title -
journal of geophysical research: planets
Language(s) - English
Resource type - Journals
eISSN - 2169-9100
pISSN - 2169-9097
DOI - 10.1029/2019je006229
Subject(s) - impact crater , asteroid , radiation pressure , radius , astrobiology , physics , orbit (dynamics) , geology , astronomy , aerospace engineering , computer security , computer science , engineering
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 order of tens of cm/s, a number of particles were surprisingly seen to orbit for multiple revolutions and days, which requires a dynamical mechanism to quickly and substantially modify the orbit to prevent re‐impact upon their first periapse passage. This paper demonstrates that, based on simulations constrained by the conditions of the observed events, the combined effects of gravity, solar radiation pressure, and thermal radiation pressure from Bennu can produce many sustained orbits for ejected particles. Furthermore, the simulated populations exhibit two interesting phenomena that could play an important role in the geophysical evolution of bodies such as Bennu. First, small particles (<1 cm radius) are preferentially removed from the system, which could lead to a deficit of such particles on the surface. Second, re‐impacting particles preferentially land near or on the equatorial bulge of Bennu. Over time, this can lead to crater in‐filling and growth of the equatorial radius without requiring landslides.