Time Accuracy Requirements for VLBI Experiments in Radio Astronomy

Abstract
This paper deals with the time accuracies required for conducting very long baseline interferometry (VLBI) experiments in radio astronomy. Some of the existing VLBI systems in USA and Japan are described. Proposed plans for VLBI at 3-m wavelength for compact radio source structure studies with very high resolution using inter-planetary scintillation radio telescopes having three baselines of 200 km each are outlined.