Mariner 7
Launch date:Nation:
Outcome: success
Wikipedia - "On July 29, 1969, less than a week before closest approach, JPL lost contact with Mariner 7. They regained the signal via the backup low-gain antenna and were able to start using the high gain antenna again shortly after Mariner 6's close encounter. It was later determined a battery onboard Mariner 7 had exploded. Based on the observations made by Mariner 6, Mariner 7 was reprogrammed in flight to take further observations of areas of interest and actually returned more pictures than Mariner 6, despite the explosion. "
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Jan 14