This research program will use the technique of Very Long Baseline Interferometry (VLBI) at millimeter wavelengths to image jets of outflowing plasma in nearby Active Galactic Nuclei (AGNs) at unprecedented angular resolution. These observations may directly measure the size of the base of the jet at a frequency of 230GHz and establish its location within the jet (in combination with the results of lower frequency observations). In collaboration with scientific partners, emission models of the jet base will be developed for comparison with the new observations. Existing VLBI simulation software will be enhanced to provide the means to properly constrain parameters of the jet models. Broader impacts involve training of students and postdoctoral scholars, enhancing instrumentation and international partnerships, and involvement of teachers in the research via the Research Experience for Teachers program.
