The VSOP mission is a Japanese-led project to study radio sources with sub-milliarcsec resolution using an orbiting 8 m telescope , HALCA , along with global arrays of Earth-based telescopes .
Approximately 25 % of the observing time is devoted to a survey of compact AGN which are stronger than 1 Jy at 5 GHz—the VSOP AGN Survey .
This paper , the third in the series , presents the results from the analysis of the first 102 Survey sources .
We present high resolution images and plots of visibility amplitude versus projected baseline length .
In addition , model-fit parameters to the primary radio components are listed , and from these the angular size and brightness temperature for the radio cores are calculated .
For those sources for which we were able to determine the source frame core brightness temperature , a significant fraction ( 53 out of 98 ) have a source frame core brightness temperature in excess of 10 ^ { 12 } K. The maximum source frame core brightness temperature we observed was 1.2 \times 10 ^ { 13 } K. Explaining a brightness temperature this high requires an extreme amount of relativistic Doppler beaming .
Since the maximum brightness temperature one is able to determine using only ground-based arrays is of the order of 10 ^ { 12 } K , our results confirm the necessity of using space VLBI to explore the extremely high brightness temperature regime .