Preliminary results from the VSOP survey program Original Research Article

Thirty percent of the scientific observing time of the VSOP mission is devoted to surveying the 402 brightest, small-diameter radio sources at 5 GHz. This program is led by scientists in Japan, and it is supported by an international team of scientists at many observatories and institutions. The major goals of the Survey project are to determine the statistical properties of the 5 GHz sub-milliarcsecond structure of the brightest radio sources and to provide a source list for use with future space VLBI missions. The VSOP Survey database will also provide a useful database for comparisons with various ground-based observations at many wavelengths. Similar surveys in the past using new technology have proven extremely valuable in the understanding of the properties of compact extragalactic radio sources. Preliminary results from the first 18 months of observations are given in this review.