Space Sciences Data Processing

Abstract

Spacecraft carrying large numbers of scientific instruments are presently transmitting data at the rate of approximately 100 million data points per day. The outputs of the sensors are partially processed on the spacecraft and transmitted to the ground. These data must then be converted from raw digital form into a conceptually meaningful form which the experimenters can analyze and from which they can draw valid conclusions about the phenomena being measured. At present the ground processing is done in several steps. The first includes conversion of the raw data acquisition station tapes into computer tapes and includes signal clean-up, establishment of synchronization, and time decoding. In the newest processing lines this first step also includes a moderate amount of editing and quality control. The rest of the steps involve large scale computers and include further editing, establishment of accurate timing, computation of the spacecraft attitude, and sorting, to provide data tapes for the individual experimenters. The experimenters have the responsibility for the further reduction to more meaningful form. These operations include further sorting, storage, compilation, computation, and display. There is at present a great need for additional development of analysis and display programs, techniques, and equipment to assist in this work.