Calibration and performance of the Galileo solid-state imaging system in Jupiter orbit

The solid-state imaging subsystem (SSI) on the National Aeronautics and Spa ce Administration's (NASA's) Galileo Jupiter orbiter spacecraft has success fully completed its 2-yr primary mission exploring the Jovian system. The S SI has remained in remarkably stable calibration during the 8-yr flight, an d the quality of the returned images is exceptional. Absolute spectral radi ometric calibration has been determined to 4 to 6% across its eight spectra l filters. Software and calibration files are available to enable radiometr ic, geometric, modulation transfer function (MIF), and scattered light imag e calibration. The charge-coupled device (CCD) detector endured the harsh r adiation environment at Jupiter without significant damage and exhibited tr ansient image noise effects at about the expected levels. A lossy integer c osine transform (ICT) data compressor proved essential to achieving the SSI science objectives given the low data transmission rate available from Jup iter due to a communication antenna failure. The ICT compressor does introd uce certain artifacts in the images that must be controlled to acceptable l evels by judicious choice of compression control parameter settings. The SS I team's expertise in using the compressor improved throughout the orbital operations phase and, coupled with a strategy using multiple playback passe s of the spacecraft tape recorder, resulted in the successful return of 164 5 unique images of Jupiter and its satellites. (C) 1999 Society of Photo-Op tical Instrumentation Engineers. [S0091-3286(99)02007-3].