Chapter 13 describes the techniques and procedures used to derive angular separations and magnitude differences of the components of multi-star systems or the angular sizes of extended objects. We will discuss the uncertainties associated with these analyses along with the procedures themselves.
We currently plan to upgrade the astrometry TRANSFER mode pipeline to perform more of the activities now carried out by the non-pipeline processing. As these upgrades come online, we will provide updated versions of this chapter via STScI's FGS WWW pages.