Thermodynamic model of the activity of the comet 103P/Hartley*

Abstract

Abstract The paper presents three processes related to the dynamics of cometary particles. The following thermodynamic mechanisms were taken into account: quiet sublimation, emission of cometary matter via jet and migration of particles on the surface of the comet 103P/Hartley. Based on the first two mechanisms, the maximum particle size that can be lifted into the coma was determined. Additionally, in the case of a jet, the angle at which it is emitted from inside the cometary nucleus was determined. However, in the case of migration, the maximum width of individual belts within which a given particle can move was determined. In the context of the discussed mechanisms related to the activity of comet 103P/Hartley, the coefficient of friction and the structure of the solid or porous particles are of key importance.