On the light-absorbing surface layer of cometary nuclei : II. Thermal modeling

摘要: Abstract The classical way to treat absorption of solar light in thermophysical modeling cometary nuclei (and other ice-rich bodies such as jovian satellites) has been assume complete opaqueness the surface material. However, shown by Davidsson and Skorov (2002, Icarus 156 , 223–248), substantial penetration can occur porous ice even if it is very dusty, implying that gradual energy a layer should be accounted for. We present thorough comparison between model model, for various combinations heliocentric distances, conductivities, opacities, pore sizes, rotational periods relevant nuclei, fully solving coupled differential equations heat transfer gas diffusion. find differences models terms production rate, thermal lag angle, temperature, origin coma molecules. For example, overestimates total factor 2–7, underestimates angle 2–3, places molecules at surface, instead near-surface interior.