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What's so special about that date? I guess in whatever datetime representation they were using, it overflowed at that point?


It seems to be approximately 2^32 tenths of second into the new millennium. Which is an odd way to do things, but I guess there were reasons.


The standard for astronomical measurements today is the J2000.0 epoch.

http://en.wikipedia.org/wiki/Epoch_%28astronomy%29#Julian_ye...


Seems so

  h> logBase 2 . realToFrac $ (secs "2013-08-11" - secs "2000-01-01")*10
  31.999992174768167


Totally off-topic, but that looks a lot like Haskell, what did you do to make ghci have such handy calculator functionality? (I can't find secs in Hoogle)


It's just

  secs = utcTimeToPOSIXSeconds . readTime defaultTimeLocale "%F"


I bet there's a:

    \\TODO: reset the clock before launch day
Somewhere that would have allowed it a ~13 years lifetime from launch day on instead of from 2000 on..


I bet that during the initial design phase, they wanted to keep the design simple, have enough timekeeping range to cover the mission and then maximize temporal resolution.

Someone realized that a counter operating on tenths of a second from 2000 was both easy to use and sufficient for the primary mission... they then thought nothing of it until the loss of contact




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