International audienceThis paper summarizes the way we obtained the physical information on the ICRF2 radio sources.This information includes the object type, redshift, 8.4 GHz and 2.3 GHz fluxes, spectral index, visual magnitude, a classification of spectrum, and comments. The physical characteristics are made available in ASCII format at the International Celestial Reference System Product Center (ICRS-PC) of the International Earth rotation and Reference systems Service (IERS) at:http://hpiers.obspm.fr/icrs-pcunder the section Information on radio source