17.2 Ground Testing and Calibration

The STIS IDT (Principal Investigator, Bruce Woodgate, GSFC) was responsible for the ground testing and ground calibration of STIS. Most of the ground test data were obtained in late 1996, during thermal vacuum testing at Ball Aerospace in Colorado, and during subsequent testing in a dry-nitrogen environment at GSFC. These tests characterized the basic properties of the optics, the detectors, and the mechanisms. Certain measurements (e.g., measurements of the quantum efficiency of the STIS detectors vs. wavelength) cannot be repeated in orbit. However, most of the ground test data have been superseded by on-orbit measurements.