Properties of the ground- and space-based astrometry dataset, supplemented by a few radar observations. Panel a: ground- and space-based astrometric and radar data, divided into five main observation types: CA (classical astrometry), SA (space-based astrometry), MP (mutual phenomena), RD (radar), SO (stellar occultation). The colour indicates the accuracy of each measurement. Panel b: accuracy of the different ground-and space-based astrometric and radar data, for each of the main observation types. On both figures, the black vertical line delimits existing data and simulated future ones. It should be noted that the accuracy of the space-based astrometry is expressed with respect to the spacecraft, and not with respect to Earth as for the other observations.