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Communications SystemHow does NASA communicate with spacecraft? |
When science telemetry data are first received by the data management system, they are stored in a time-ordered data base. It is common for large segments of this data to be missing. A data management team must first determine what gaps exist and determine whether or not they can get the data back. Some data are easily recoverable because they actually reached the ground and were recorded either at a DSN station or at some intermediate subsystem--but were missing in the end due to some failure. Once identified and located, recovered data are transferred to data management system storage and integrated with data received earlier.
The problem is more time consuming if DSN station problems or sudden rain over a station prevented reception of the data. In such cases, if the data are of great value, the project may be able to recover them by commanding the spacecraft to replay a specific portion of the tape it keeps--but that has to happen before the tape is overwritten by new data.
How much time on the Deep Space Network is DS1 getting?
