Ivanova O. Physical model of local active areas on a surface of cometary nucleus

The main results of the active region on surface a comet nucleus physical model construction and investigation of this model are presented in the Theses. It was shown that the crater structure model in the form of a conic hole explains well observed effects of sublimation increasing from a comet nucleus and temperature variations on a comet nucleus surface in the case of active regions availability. Meteoroid impact, as one of the possible mechanisms of the crater structure on a comet nucleus surface formation, was investigated in details. The probability of simultaneous existence of several craters on a comet nucleus and its dependence on the lifetime and crater formation frequency were calculated. The investigation of the temperature regime on crater structure ice bottom and dusty walls dependence on an active region location - on a cometary nucleus pole or arbitrary location on the rotating nucleus - was carried out. It was obtained that in a case of crater structure availability on a comet surfacethe specific radiation flux is three times greater than in a case of absence of such structure. The effect of ice sublimation increasing from the crater structure for active region physical model in a case of rotation absence (active region is located on the comet nucleus pole) and in a case of arbitrary comet nucleus rotation was investigated. The influence of crater structure geometry on general sublimate flux from active region was examined.