Seminar in lithosphere and planetology physics
Landslides and dynamics of slow ejecta on comets
dr hab. Leszek Czechowski
Instytut Geofizyki, Wydział Fizyki, Uniwersytet Warszawski
Oct. 6, 2017, 9:30 a.m.
ul. Pasteura 5, sala B4.58
Model of comet 67P/Churyumov–Gerasimenko is used for consideration of dynamics of landslides on small celestial bodies. The gravitational field of this comet is very complicated and equipotential surfaces are dramatically different than the physical surface. Only 19% of the area has the slope below 10o. Here, we consider slow ejecta as material for the possible landslide’s deposits. This ejecta could be a result of an impact or of an internal activity. We find that for the velocity 0.3 m s-1 or lower, the ejecta land usually close to the starting point. Ejecta faster than 0.5 m s-1 have complicated trajectories and could land far from the starting point. Generally, we find that Keplerian orbits are useless for navigation close to small irregular celestial bodies.