Cometary splitting due to thermal stresses

We consider the thermal evolution of icy solids moving on the highly eccent ric orbits on the base of the numerical solution of the non-linear heat dif fusion equation. Thermal stresses which arise inside of solids and at their surface can exce ed the tidal stresses by several orders of magnitude in the neighborhood of the Sun and play an important and, perhaps, a crucial role in the evolutio n of comets. A possible disintegration scenario of a distant icy solid due to thermal st resses is presented. (C) 1999 Elsevier Science Ltd. All rights reserved.