Skip to main content
SearchLoginLogin or Signup

Dynamic Evolution of Asteroid Shape and Spin from the YORP Effect

Presentation #212.09 in the session MBAs: Physical Characteristics (iPosters).

Published onOct 20, 2022
Dynamic Evolution of Asteroid Shape and Spin from the YORP Effect

Asteroid surface evolution is distinctly coupled with long-term spin behavior through the YORP effect. This dynamic influence can cause large changes in the spin state and obliquity as the effect compounds on each rotation. This in turn causes small changes in the surface slope distribution and regolith migration which contributes to a feedback loop between the surface and spin [1][2]. This work aims to characterize the changes in YORP coefficients of a particular body over time due to the motion of free boulders and random cratering events on the surface of a rubble-pile asteroid below 10 km in diameter. This will be done via soft-sphere distinct element simulation of the microgravity environment [3].The re-evaluation of the YORP coefficient as the surface changes is necessary to model possible feedback behavior. The trend can be closely examined in order to better characterize the patterns of the traditional YORP cycle as it spins up to fission and down to chaotic tumbling states [4]. Previous work considers YORP to have a stochastic impact on the long-term dynamics of a small body, however this stochasticity could be constrained with higher fidelity simulations of rubble-pile asteroids [5]. This work expands upon previous efforts to simulate asteroid surface behavior by tracking the YORP coefficient’s coevolution to further inform the assumed stochastic nature of asteroid belt population dynamics over time.

[1] Scheeres, D. J. (2007). The dynamical evolution of uniformly rotating asteroids subject to YORP. Icarus, 188(2), 430–450. [2] Lupishko, D. F., Mikhalchenko, O. I., & Chiorny, V. G. (2019). Influence of the YORP Effect on the Rotation of Small Main-Belt Asteroids. Solar System Research, 53(3), 208–214. [3] Sánchez, P., & Scheeres, D. J. (2011). Simulating asteroid rubble piles with a self-gravitating soft-sphere distinct element method model. Astrophysical Journal, 727(2). [4] Hirabayashi, M., Scheeres, D. J., Chesley, S. R., Marchi, S., McMahon, J. W., Steckloff, J., Mottola, S., Naidu, S. P., & Bowling, T. (2016). Fission and reconfiguration of bilobate comets as revealed by 67P/Churyumov-Gerasimenko. Nature, 534(7607), 352–355. [5] Statler, T. S. (2009). Extreme sensitivity of the YORP effect to small-scale topography. Icarus, 202(2), 502–513.

No comments here