Chapter 1:
Instrument Overview

1.1 Instrument Capabilities

1.1.1 The FGS as a Science Instrument

1.2 Technical Overview

1.2.1 The Instrument

1.2.2 Modes of Operation

1.2.3 FGS Capabilities

1.2.4 FGS Control

1.3 Target Acquisition and Tracking

1.3.1 Search

1.3.2 CoarseTrack

1.3.3 FineLock

1.3.4 Transfer Scans

1.4 FGS Guiding

This chapter presents a brief overview of the scientific capabilities of the Fine Guidance Sensors, their readout modes, and data products. The material presented here is excerpted from the information presented in the FGS Instrument Handbook, and we refer the reader to that document for more complete information about the properties of the FGS as a science instrument.