Eli5: Voyager spacecrafts tackling bit flips

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How do Voyager spacecrafts handle bit flips due to cosmic radiation outside the solar system. As far as I know, the amount of cosmic radiation is a lot higher outside the solar system/termination shock/ heliopause area. This means that there more chances of bit flips.
And afaik, Voyager only has 70KB of memory, so I don’t think redundancy is an option, as at least 2 more replicas would be required(best of 3).

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Anonymous 0 Comments

Unfortunately I don’t know what data integrity techniques are used on voyager, but I wanted to correct one of your assumptions:

By encoding things well, you can actually do significantly better than a ‘best 2 of 3’ mirrored array. One example of such a scheme is called [Hamming code.](https://www.youtube.com/watch?v=X8jsijhllIA) The youtube video does a far better in-depth job than I could of explaining how it works, but the very short version is that it uses a bunch of interlocking parity checks to detect bad data and ungarble it, and does so with better resiliency (against *small* recoverable errors) and data-efficiency than regular mirroring. Just thought you might be interested to know about this. A [related video by Ben Eater](https://www.youtube.com/watch?v=h0jloehRKas) demonstrates how you can implement this style of error-correction in hardware.