Undoubtedly, given the evidence we have to this point, the compiler was clearly capable of making further errors and slips along the way, and thus we need not be surprised to find the three remaining ‘seconds’ values not precisely matching.
Although I am not in any way proposing that this is the source of the difference seen in the seconds column for 1982, it is worth noting that if we replace the event time of 21:45h UT with a rounded 20:00h UT, then application of our running model will again produce the artefact value, 5h 51m 21s, precisely. However, here we are clearly at risk of merely manipulating our data to produce the results we expect. The fact that the adjusted time falls precisely on 20:00 is, however, of interest.
“This isn’t right! It’s not even wrong!”—Wolfgang Pauli (1900–1958)