The VSOP Survey is a program to systematically observe with ultra-high resolution the cores of the brightest active galactic nuclei (AGN). A flux-density limited sample of AGN is observed at 5GHz in order to derive complete statistical information on their sizes and brightness temperatures.
The VSOP survey makes use Halca, in conjunction with ground radio telescopes, in order to obtain baselines of unprecedented length. The orbit of Halca generates VLBI baselines that are typically two to three times longer than can be obtained with solely ground-based VLBI.
Approximately 25% of the observing time with Halca is devoted to the survey, which is recorded in S2-format and correlated in Penticton, British Columbia and Mitaka, Japan. Analysis of the survey data is carried out by a collaboration of survey data analysts from Japan, Canada, the United States, and Australia.
to the University of Calgary Space VLBI Web Page.