The VSOP Survey: final aggregate results

In February 1997 the Japanese radio astronomy satellite HALCA was launched to provide the space-borne element for the VSOP mission. HALCA provided linear baselines three-times greater than that of ground arrays, thus providing higher resolution and higher AGN brightness temperature measurements and limits. Twenty-five percent of the scientific time of the mission was devoted to the “VSOP survey” of bright, compact, extra-galactic radio sources at 5 GHz. A complete list of 294 survey targets were selected from pre-launch surveys, 91% of which were observed during the satellite's lifetime. The major goals of the VSOP Survey are statistical in nature: to determine the brightness temperature and approximate structure, to provide a source list for use with future space VLBI missions, and to compare radio properties with other data throughout the electro-magnetic spectrum. All the data collected have now been analysed and is being prepared for the final image Survey paper. In this paper we present details of the mission, and some statistics of the images and brightness temperatures.