BIANCHI, SimoneSimoneBIANCHI2023-01-262023-01-26200507354024690094-243Xhttp://hdl.handle.net/20.500.12386/33066I review the results of our Monte Carlo models for the radiative transfer in the dusty disks of spiral galaxies. The simulations are compared to observations of dust extinction in the optical and emission in the FIR, with the aim of deriving the amount of interstellar grains, their distribution and the internal extinction in a galaxy. I discuss the main, puzzling, result of this comparison: more dust is needed to explain thermal emission than what is inferred from extinction studies.STAMPAenConference paper10.1063/1.19139282-s2.0-33748568098https://api.elsevier.com/content/abstract/scopus_id/33748568098https://aip.scitation.org/doi/pdf/10.1063/1.19139282005AIPC..761..178BFIS/05 - ASTRONOMIA E ASTROFISICA