The effect of local topography and self-heating on the sublimation rate of cometary nuclei

This work presents the results of calculation of the temperature regime and total flux of sublimation for a new physical model of local active areas on a cometary nucleus. As it was shown before a conical hole in the surface dust layer of a cometary nucleus can work as a concentrator of solar energy and, therefore, intensifies sublimation. The temperature of ice on the bottom and that of dust on the side of the crater is calculated for different geometrical parameters of the crater and different conditions of rotation of the nucleus. The dependence of the effect on the location of the active region as well as the effect of changing the solar zenith angle is studied.