A famous example is NASA, whose early space records have suffered from a dark age issue more than once. For over a decade, magnetic tapes from the 1976 Viking Mars landing were unprocessed. When later analyzed, the data was unreadable as it was in an unknown format and the original programmers had either died or left NASA. The images were eventually extracted following many months of puzzling through the data and examining how the recording machines functioned. The original Moon landing tapes were likely erased and reused, with the only video recordings of the Apollo 11 landings being later copies.

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