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potatiumyesterday at 10:34 PM1 replyview on HN

Not sure if it's more of an urban legend, but the old story went that one (or two?) Soviet Mars probes in the 80s went wildly off course because of the typo in their nav software, allegedly written in Fortran. A comma was misplaced for a dot.


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gshubert17yesterday at 11:32 PM

Susan Stepney's web page https://www-users.york.ac.uk/~ss44/cyc/p/fbug.htm describes a Fortran bug urban legend, in which

when DO I = 1.100 was used instead of DO I = 1,100

Mariner I, a spacecraft bound for Venus, was lost July 22, 1962 due to a combination of hardware failure and software error, https://en.wikipedia.org/wiki/Mariner_1#Cause_of_the_malfunc... . (I misremembered this as a similar Fortran error.)