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db48x
That has to hurt. I would really love to read an in–depth analysis of the problem.
_boffin_
One engineer: do we need to account for leap year?

Other engineer: it wasn’t in the specs.

db48x
It was probably a manager that said it wasn’t in the spec, but yea, that is entirely plausible :(
BenFranklin100
Yep. I’ve heard that one before. Either they have a lack of common sense or they stopped caring enough to ask questions.
cbxjksls
rolling your own time library is as crazy as rolling your own crypto
gruez
To be fair most time libraries suck and can't handle fairly basic operations. For instance, if you're using python's datetime module and want to get the start/end dates of the current month, you need to "roll your own" like

    now = datetime.now()
    month_start = date(now.year, now.month, 1)
    month_end = date(now.year, now.month + 1, 1) - timedelta(days=1)
brianwawok
So in Dec your code hits month 13? Kinda funny in a post how rolling your own time library is easy we made trivial bugs
[deleted]
(comment deleted)
gruez
That's the point. I'm not advocating rolling your own date logic, only pointing out how easy it is to for "roll your own" logic to make its way into code even if if you're using a datetime library.
MadnessASAP
If you're going to copy my code onto HN I would appreciate attribution.

/s

ainiriand
You probably haven`t used phps Carbon.
Caligatio
You should use: calendar.monthrange
nitwit005
The typical time libraries don't deal with satellites. Clocks are running at a slightly different rate in orbit.
JPLeRouzic
“The root cause was identified as a software issue within the ground segment”
nitwit005
Yes, a thing that interacts with satellites, where you would expect that code to be.
weird_tentacles
Some degree of effort is required to _not_ use et (Ephemeris Time) and, by practice, a spacecraft clock adjustment (SCLK) would be initially loaded.

The developers would have gone through this routine (initially load SCLK, use Ephemeris Time) literally _thousands_ of times in their coding, developing ... preparing, making .... careers. It's the SPICE baby.

so .... WTF?