Thermal Fatigue as a Driving Mechanism for Activity on Asteroid Bennu.

ABSTRACT: Many boulders on (101955) Bennu, a near-Earth rubble pile asteroid, show signs of in situ disaggregation and exfoliation, indicating that thermal fatigue plays an important role in its landscape evolution. Observations of particle ejections from its surface also show it to be an active asteroid, though the driving mechanism of these events is yet to be determined. Exfoliation has been shown to mobilize disaggregated particles in terrestrial environments, suggesting that it may be capable of ejecting material from Bennu's surface. We investigate the nature of thermal fatigue on the asteroid, and the efficacy of fatigue-driven exfoliation as a mechanism for generating asteroid activity, by performing finite element modeling of stress fields induced in boulders from diurnal cycling. We develo

SUBMITTER: Molaro JL 

PROVIDER: S-EPMC7507781 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature