摘要：Context.The thermal conductivity of highly porous dust aggregates is a key parameter for many subjects in planetary science; it is not yet fully understood, however.Aims.We investigate the thermal conductivity of fluffy dust aggregates with filling factors lower than10-1.Methods.We determined the temperature structure and heat flux of the porous dust aggregates calculated throughN-body simulations of static compression in the periodic boundary condition.Results.We derive an empirical formula for the thermal conductivity through the solid networkksolas a function of the filling factor of dust aggregatesφ. The results reveal thatksolis approximately proportional toφ2, and the thermal conductivity through the solid network is significantly lower than previously assumed. In light of these findings, we must reconsider the thermal histories of small planetary bodies.
