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7.8 Lost Data Lines

  Occasionally, dropouts or the garbling of data recorded on the spacecraft tape recorder led to the loss of whole lines, or contiguous, small groups of lines. Fortunately, we had encoded the line number and data packet number ahead of the pixel data in each packet of data sent to the spacecraft tape recorder. This provided the basis for the data retrieval software to locate correctly the surviving lines in exposures that had been corrupted by the tape recorder dropouts.

Losses occurred for only 0.36% of all of our data. When we derived spectra, these missing pieces were treated in the same manner as bad pixels and columns; they had zero weight in the final additions.