Command and control of unmanned scientific spacecraft

Recent developments in command and control technology for use with the Voyager and the planned Galileo are discussed. These spacecraft each carry more than 10 scientific instruments, many of which are very complex, and these instruments must be able to function with a considerable degree of autonomy because the round-trip light time to the spacecraft in the vicinity of Jupiter and Saturn is too great to permit prompt ground-based management of onboard anomalies or control of some observation programs. Command and control procedures, including data storage procedures, for systems of the two spacecraft are examined.